The Neurocritic

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Deconstructing the most sensationalistic recent findings in Human Brain Imaging, Cognitive Neuroscience, and Psychopharmacology

The Neurocritic
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December 17, 2008
10:46 PM
898 views

Crime, Punishment, and Jerry Springer

by The Neurocritic in The Neurocritic

RT @Dostoyevsky Realists do not fear the results of their study."Good God!" he cried, "can it be, can it be, that I shall really take an axe, that I shall strike her on the head, split her skull open... that I shall tread in the sticky warm blood, blood... with the axe... Good God, can it be?"- Fyodor Dostoevsky, Crime and Punishment, Ch. 5A new fMRI paper in Neuron (Buckholtz et al., 2008) claims to have discovered the neural correlates of evaluating another person's crime and deciding on the appropriate sentence, in emulation of judges and juries meting out third-party punishment (Fehr & Fischbacher, 2004).On the other hand, the rotating "freak show" guests on the Jerry Springer Show mete out second-party punishment,1 which is generally harsher (in midget fights and certain economic games, at least).Here’s the great new insight of the paper, according to the Preview by Johannes Haushofer and Ernst Fehr:Thus, the study of Buckholtz makes a valuable contribution in that it illustrates that third-person judgment situations, such as those used in their study, may rely on similar neural mechanisms as two-person economic and social exchanges. While it is difficult to draw reverse inferences about mental states based on brain activation (Poldrack, 2006),2 one might speculate, based on this new study, that the mental processes motivating judicial verdicts involve the suppression of prepotent emotional reactions in favor of impartial and objective verdicts.[NOTE: aren’t you just marveling at this grand new insight from fMRI? Like we didn’t already know that judges and jurors must put aside their emotionally-driven desire for revenge when coming to an impartial verdict.]Thus, this new result might, if confirmed by future studies, elucidate the neural source of judicial impartiality.All right, let's go back to the beginning. Or to the Methods, at least. One of the experimental tasks was to determine whether the perpetrator of a given hypothetical crime was responsible for his actions. There were two versions of the same basic crime scenarios with the details of Responsibility versus Diminished Responsibility counterbalanced across the two sets (e.g., compare #3 and #32 below). Half of the participants read Set 1, the other half read Set 2. Some of the infractions were minor (#7, #22), but some were crimes of the most heinous sort, whether intentional (#3) or unintentional (#27, #32). Thus, the severity of the crimes was matched across the experimental conditions as well. Below are some examples of the stimuli, taken from the Supplementary Materials. Responsibility Scenarios 3) John develops a plan to kill his 60-year-old invalid mother for the inheritance. He drags her to her bed, puts her in, and lights her oxygen mask with a cigarette, hoping to make it look like an accident. His mother screams as her clothes catch fire and she burns to death. 7) John is parking his car in the parking lot of a local football stadium, where he plans to watch a game. In the car next to his, he sees a hat with his team logo in the back seat. Seeing that the door is unlocked, John opens the door, and takes the hat. Diminished Responsibility Scenarios 22) John visits a local bookstore, carrying a large shopping bag with goods from another store. While the store clerk is preoccupied with inventory, another customer, hoping to use John unwittingly in a theft, sneaks a book into John’s shopping bag. Without realizing what has happened, John walks out without paying for the book. 27) A brain tumor is causing increasingly erratic, violent, and callous behavior in John. Soon, he develops an uncontrollable urge to kill. John abducts a boy, puts a broomstick in the boy’s r-----, and lashes him with a whip until he dies. When the tumor is later found and removed, John’s behavior returns to normal. 32) Unbeknownst to John and his doctors, his new prescription interacts with his other medications to induce severe acute psychoses. During that interaction, John returns home to his 60-year old invalid mother, who he has always adored. John lights her oxygen mask with a cigarette, and watches as his mother catches fire, screams, and burns to death. No Crime Scenarios [control condition] 47) The manual to John’s new car states: “The oil must be changed no less frequently than every 4,000 miles.” John reads the manual and is aware of what it says. However, John drives the car for 4,023 miles before taking it to a service station for the car’s first oil change. [gasp!] 48) John and his best friend have played golf together for more than ten years. They used to be evenly matched, but recently John’s friend has consistently outplayed him. Growing frustrated, John responded by taking private golf lessons from the local pro. The next time John played against his friend, he soundly beat him.That was extremely unpleasant and harsh at times, wasn't it? Over the course of the experiment, participants read 50 scenarios (20 Responsibility, 20 Diminished Responsibility, 10 No Crime) three times each: once in the scanner and twice after scanning. The procedures were as follows:Participants rated each scenario on a scale from 0–9, according to how much punishment they thought John deserved, with “0” indicating no punishment and “9” indicating extreme punishment. Punishment was defined for participants as “deserved penalty.”. . .Following the scanning session, participants rated the same scenarios along scales of emotional arousal and valence. They first rated each of the 50 scenarios (presented in random order on a computer screen outside the scanner) on the basis of how emotionally aroused they felt following its presentation (0 = calm, 9 = extremely excited). They then rated each of the scenarios, presented again in random order, on the basis of how positive or negative they felt following its presentation (0 = extremely positive, 9 = extremely negative).The results from these rating tasks are shown below, and it's not surprising that the subjects recommended more severe punishments for the perpetrator in the Responsibility scenarios than in the Diminished Responsibility scenarios.Figure 1 (Buckholtz et al., 2008). Punishment and Arousal Ratings for Each Scenario Type. While punishment and arousal scores were similar in the Responsibility condition, punishment scores were significantly lower than arousal scores in the Diminished-Responsibility condition. Error bars = SEM.As for the neuroimaging results, the authors compared the hemodynamic response in the Responsibility versus the Diminished Responsibility conditions to see what brain areas might be differentially activated. Greater activity in the right dorsolateral prefrontal cortex (rDLPFC) was emphasized (Fig 2). Responses in bilateral anterior intraparietal sulcus were similar, but relegated to the Supplementary Materials.Figure 2 (Buckholtz et al., 2008). Relationship between Responsibility Assessment and rDLPFC Activity. (A) SPM displaying the rDLPFC VOI, based on the contrast of BOLD activity between the Responsibility and Diminished-Responsibility conditions. (B) BOLD activity time courses. BOLD peak amplitude was significantly greater in the Responsibility condition compared with both the Diminished-Responsibility and No-Crime conditions.So now we get to the interpretation that rDLPFC is suppressing emotional reactions in areas such as the amygdala, medial PFC, and posterior cingulate cortex (which were sensitive to the magnitude of punishment) in order to assign a diminished level of criminal responsibility. The problem with that reverse inference is illustrated below.This figure was generated from entering the x, y, z Talairach coordinates from the rDLPFC focus shown above (39, 37, 22)3 into the Sleuth program (available at brainmap.org), which searched the available database of papers for matches. The resulting list of coordinates and experiments was then imported into the GingerALE program, which performed a meta-analysis via the activation likelihood estimation (ALE) method (see this PDF). The figure illustrates that the exact same region of rDLPFC was activated during tasks that assessed attention; execution, inhibition, and observation of actions; various aspects of language and perception; and especially working memory.The authors appear to acknowledge the caveat thatthe brain regions identified in our study are not specifically devoted to legal decision-making. Rather, a more parsimonious explanation is that third-party punishment decisions draw on elementary and domain-general computations supported by the rDLPFC.They also acknowledged the confound of arousal and crime severity. Nonetheless, they concluded by waving their arms around and blabbing about the evolution of the legal system:...on the basis of the convergence between neural circuitry mediating second-party norm enforcement and impartial third-party punishment, we conjecture that our modern legal system may have evolved by building on preexisting cognitive mechanisms that support fairness-related behaviors in dyadic interactions. Though speculative and subject to experimental confirmation, this hypothesis is nevertheless consistent with the relatively recent development of state-administered law enforcement institutions, compared to the much longer existence of human cooperation.What are we to conclude from this? Since it's very late now, I'll let Jerry and Fyodor have the last words.“We can't just have mainstream behavior on television in a free society, we have to make sure we see the whole panorama of human behavior.”- Jerry Springer“Actions are sometimes performed in a masterly and most cunning way, while the direction of the actions is deranged and dependent on various morbid impressions-it's like a dream.”- Fyodor Dostoevsky, Crime and Punishment, Ch. 17But when all is said and done, why don't we let Jerry Fodor have the last word?“It’s a thin line between clarity and pomposity.” — Psychosemantics: The Problem of Meaning in the Philosophy of Mind, p. 17.Footnotes1 But as Wikipedia notes, "there has been continuous debate over the actual authenticity of the fighting."2 "...we won’t let that stop us from rampant speculation" [to paraphrase Haushofer and Fehr]. I feel like a broken record here, but reverse inference is a logical fallacy - one cannot directly infer the participants' cognitive or emotional state from the observed pattern of brain activity. Everyone should know better by now, and there should be a moratorium on such sloppy thinking. Or rather, such sloppy writing and publishing. The high-profile journals are the worst offenders, and they end up promoting the use of totally misleading headlines like this one:Justice may be hard-wired into the human brainCall it the justice instinct. When judging the guilt or innocence of alleged criminals, our brains seem to respond as if we were personally wronged, say researchers.The "justice instinct"?? Spare me. The experiment said absolutely nothing about evolution, genetics, or "hard-wiring."3 According to pages 932 and 938. However, page 936 and Table S1 say the coordinates are slightly different: 39, 38, 18.ReferencesJ BUCKHOLTZ, C ASPLUND, P DUX, D ZALD, J GORE, O JONES, R MAROIS (2008). The Neural Correlates of Third-Party Punishment. Neuron, 60 (5), 930-940 DOI: 10.1016/j.neuron.2008.10.016.Fehr E, Fischbacher U. (2004). Third-party punishment and social norms. Evolution and Human Behavior 25:63–87.Haushofer J, Fehr E (2008). You Shouldn’t Have: Your Brain on Others’ Crimes. Neuron 60:738-740.Ax Murderer FAIL... Read more »

J BUCKHOLTZ, C ASPLUND, P DUX, D ZALD, J GORE, O JONES, & R MAROIS. (2008) The Neural Correlates of Third-Party Punishment. Neuron, 60(5), 930-940. DOI: 10.1016/j.neuron.2008.10.016

May 26, 2008
05:01 PM
897 views

You're My Favorite Person...

by The Neurocritic in The Neurocritic

Japanese actress and singer Ryoko Hirosue...and watching your movies boosts my peripheral levels of dopamine and circulating natural killer cells, and activates my medial prefrontal cortex, thalamus, hypothalamus, subcallosal gyrus, posterior cingulate cortex, superior temporal gyrus, and cerebellum.Fig. 3 (Matsunaga et al., 2008). Statistical parametric maps (SPM99) showing significant increases in the rCBF in the positive condition minus those in the control condition. (a) Activations of the MPFC and thalamus (TH). (b) Activations of the hypothalamus (HYP)... Read more »

M MATSUNAGA. (2008) Associations among central nervous, endocrine, and immune activities when positive emotions are elicited by looking at a favorite person. Brain, Behavior, and Immunity, 22(3), 408-417. DOI: 10.1016/j.bbi.2007.09.008

Biology

April 2, 2009
09:24 PM
897 views

Heterotopagnosia: When I point at parts of your body

by The Neurocritic in The Neurocritic

Heterotopagnosia is an unusual neurological syndrome, as described below by Laurent Cleret de Langavant and colleagues:Heterotopagnosia is the acquired inability of brain-lesioned patients to point at someone else's body parts when prompted. The cognitive basis of this disorder is unclear. It might result from a biological function deficit critical for communication in human beings; alternatively, it could result from the disruption of a body representation. Here, we report three patients with heterotopagnosia following a recent left parieto-occipital stroke and a previous insular lesion. The patients were tested on their ability to name, point out and grasp several targets including body parts (own, real others’ and figurative others’). Language, visuo-spatial deficits or any confounding neuropsychological disorders were controlled for. We found that the patients erroneously pointed to their own body parts when asked to point at someone else's. Strikingly, their ability to grasp someone else's body parts was largely unimpaired. The dissociation between their grasping and communicative pointing abilities supports the hypothesis that heterotopagnosia is a disorder of communicative function conveyed by pointing but not by grasping. In addition, pointing performance in our patients varied according to the target: the more similar the target was to a real person, the worse the patients’ pointing performance. We suggest that communicative pointing might require a specific representation of the addressee's body and point of view, a heterocentric representation. In the patients described here this phenomenon resulted from a combined insulo-parietal lesion, which may explain why, in contrast to other patients described previously, the heterotopagnosia was long-lasting.The area of maximum lesion overlap was a region in the left parieto-occipital cortex, as shown in this drawing depicting the area of damage shared by all three patients.Fig. 3. (Cleret de Langavant et al., 2009). The overlap of the left parieto-occipital junction lesion (Brodmann area 19), common to all three patients. Note that there is no overlap within the insular region for the three patients since COG has a left insular lesion and ROM and BEG a right one.What can explain this unusual disorder? First, the authors ruled out several possibilities:The features of heterotopagnosia set this pointing disorder apart from any other known neurological disorder. The patients’ preserved performance in grasping and touching body parts rules out any causal visual or spatial impairment based on the size, type, complexity or componential analysis of the target. Likewise, a language deficit cannot account for the patients’ performance in pointing. The spared ability of patients in naming body parts they cannot point to, their use of possessive and demonstrative grammatical indices and their perfect understanding of pointing exclude a category-specific lexical impairment.Instead, they suggested the patients exhibited a deficit selective for another person's body, problems with self-referencing behavior, and a dissociation between impaired pointing versus intact grasping/touching. The authors concluded by asking......why is pointing interesting if its impairment has no consequences in daily life? We suggest that pointing is a residual function that is fundamental in infant development. It marks the construction of the three-way relationship of communication (self-addressee-object or I-you-he/she/it), as a keystone for the development of language and theory of mind. In adults, its impairment is compensated by abilities that have integrated and supplanted it, leaving intact relationships with others (e.g. verbal communication and knowledge concerning others).ReferenceCleret de Langavant, L., Trinkler, I., Cesaro, P., & Bachoud-Lévi, A. (2009). Heterotopagnosia: When I point at parts of your body. Neuropsychologia DOI: 10.1016/j.neuropsychologia.2009.02.016... Read more »

Cleret de Langavant, L., Trinkler, I., Cesaro, P., & Bachoud-Lévi, A. (2009) Heterotopagnosia: When I point at parts of your body. Neuropsychologia. DOI: 10.1016/j.neuropsychologia.2009.02.016

March 19, 2009
02:25 PM
893 views

Lie To Me on the Autobiographical Implicit Association Test

by The Neurocritic in The Neurocritic

Lie to Me - Season 1 - "Moral Waiver" - Monica Raymund as Ria Torrescourtesy Adam Taylor/FoxLie detection is all the rage with the new TV show based on Paul Ekman's work1 that uses "microexpressions" to detect deception.The use of brain imaging technologies as lie detectors, and the admissibility of data obtained in this fashion as evidence in a court of law, has a high media profile as well - most recently (and notoriously) because of a juvenile-sex-abuse case in San Diego, recounted by Wired Science. The Stanford Center for Law & the Biosciences Blog has sounded the alarm in their post, No Lie MRI being offered as evidence in court:The case is a child protection hearing being conducted in the juvenile court. In brief, and because the details of the case are sealed and of a sensitive nature, the issue is whether a minor has suffered sexual abuse at the hands of a custodial parent and should remain removed from the home. The parent has contracted No Lie MRI and apparently undergone a brain scan... The defense plans to claim the fMRI-based lie detection (or “truth verification”) technology is accurate and generally accepted within the relevant scientific community in part by narrowly defining the relevant community as only those who research and develop fMRI-based lie detection.The Neurocritic weighed in on the overblown nature of these claims three years ago, with Brain Scans and Lie Detection: True or False?, Would I Lie to You?, and More Lies... Damn Lies... But even better, check out the excellent Deception Blog for an updated overview of the field.Given the high cost and dubious accuracy of fMRI technologies -- as well as the questionable accuracy of older EEG and polygraph methods -- there has been some interest in developing faster, easier, more reliable lie detection methods. Ian Sample at the Guardian's Science Blog went with this futuristic headline about the potential use of pupillometry as a routine security screening measure:Homeland Security seeks Bladerunner-style lie detectorDo our eyes betray us when we lie? The US government hopes to find out. . .Under the Small Business Innovation Research programme, the department has asked tech companies to bid for contracts to kick-start research in the area. Such a system, if it works, would undoubtedly be useful at airports and other high-security points.Here's the original SBIR solicitation for applications, which were due in February 2008:TITLE: Assess Ability to use Eye Tracking and Pupil Dilation to Determine Intent to DeceiveDESCRIPTION: Recent government sponsored research is working to produce a new line of flexible physiological and behavioral sensor technologies that are to be available for homeland security applications. These sensors, which must be non-invasive in nature and protect the privacy of the individual(s) involved, will be used to support human centered/behavioral screening processes in a variety of high and low volume venues. Security screening is conducted to evaluate the risk of individuals entering transportation and other critical infrastructure and requires efficient, rapid and accurate examination of a person. Persons involved in or planning to be involved in possible malicious or deceitful acts will show various behavioral or physiological abnormalities. Much of the technology and publications to date have focused on detection of guilty individuals using electrodermal measures. Research into other psychophysiological measures or the mechanisms underlying deception is still in its early stages. Early research has shown that pupil size varies with changes in a person's cognitive processing load. Current but unproven studies suggest that a cognitive decision to deceive or practice deception will result in a increased pupil size due to the greater cognitive processing required in comparison to truthful recall. An assessment study to determine the correlation between Pupillometry (dilation and contraction of the pupil relative to observed stimulus or emotion) and intent to deceive is required.For the ultimate in low-cost methods for lie detection, computerized reaction time tasks take the cake. An article about one of these appeared last year in Psychological Science (Sartori et al., 2008). The task they used is a variant of the Implicit Association Test (IAT) franchise that pits competing response tendencies against each other. Without getting into a lengthy discussion of the IAT, and the debates between its proponents and detractors,2 the autobiographical IAT (aIAT) employed by Sartori et al. ......allows one to evaluate which of two contrasting autobiographical events is true for a given individual. This is accomplished by requiring the respondent to complete two critical blocks of categorization trials, each of which pairs a different potentially autobiographical event with true events. Because pairing of a truly autobiographical event with true events should facilitate responses, the specific pattern of response times (RTs) in the two blocks indicates which autobiographical event is true and which is false.The participants saw different types of sentences and had to classify them as true/false or guilty/innocent. Examples of the different stimuli are listed below.adapted from Table 2 (Sartori et al., 2008).The real trick was in the way these sentence types were matched to response keys. In a series of five blocks of trials, the subjects were told to respond to each sentence as rapidly as possible. Across five experiments (each of which had a different kind of "guilty knowledge"), the order was Block 1: logical discrimination (true/false) - Block 2: initial autobiographical information (guilty/innocent) - Block 3: initial double categorization (false/innocent and true/guilty) - Block 4: reversed autobiographical discrimination (false/true) - Block 5: reversed double categorization (true/innocent and false/guilty). The order of the critical blocks 3 and 5 was counterbalanced across participants (as was the order of 2 and 4, which counterbalanced the response mapping for autobiographical trials accordingly). The key measure was the comparison between RTs to the double categorization trials in Blocks 3 and 5 -- innocent participants were expected to be slower on the "conflict" trials in which true/guilty and false/innocent were matched to the same response key, while guilty participants (who always denied their crimes) were expected to show the opposite pattern, which would reveal they were lying about their innocence.For the mock crime of stealing a CD for example, the results looked like this for the pairings of true/guilty and true/innocent:Fig. 1C (Sartori et al., 2008). For Experiment 2, results are shown for the critical block associating true sentences with guilty sentences and for the critical block associating true sentences with innocent sentences.Because the tests were able to discriminate between true and false events with 91% accuracy, the authors concluded that "the aIAT is an accurate method of detecting concealed knowledge that outperforms currently available lie-detection techniques." However, a brand new paper by Verschuere et al. (2009) has demonstrated that it's easy to fake your results in this aIAT! Oops. What Verschurere and colleagues did was provide the participants with instructions on how to beat the test. Before performing the aIAT a second time, they were told to slow down their responses in the true/guilty mapping condition. And the results for the faking version of the aIAT classified the majority of guilty liars as innocent. Imposing a response deadline, so the subjects had to respond within 1200 msec, did not alter the results.So there you have it. An extremely easy method for faking your results on the aIAT. In the past, The Neurocritic has taken the Human or Alien? test and the Dead or Alive? test. Turns out I'm neither human nor alien, and neither dead nor alive. Read those posts, and then try the tests yourselves.Footnotes1 However, as noted recently by World of Psychology, a paper by Bond (2008) questioned whether Ekman et al. (1991, 1999) omitted data unfavorable to their previously reported lie detection success rate of 73% in some federal agents. 2 The sadly defunct blog Mixing Memory was particularly critical of the IAT:The IAT isn't the only test of implicit "attitudes." . . . However, the IAT is the most popular, and has received a great deal of attention in the popular press, due in large part to a public relations campaign by its authors and the NSF and NIMH. In my mind, giving the IAT so much publicity is the most irresponsible thing I've seen in psychology since I began studying it... While the IAT has been publicized (by its authors!) as a measure of implicit attitudes, and even more, as a measure of implicit prejudice, there is no real evidence that it measures attitudes, much less prejudices. In fact, it's not at all clear what it measures, though the fact that its psychometric properties are pretty well defined at least implies that it measures something. On top of that, the IAT (like all of the other implicit tests) has serious methodological flaws that are currently being discussed in the literature. It's just irresponsible to publicize work, and claim that it does something very particular, when the work is still in the early stages and it's not at all clear what it's actually doing (read paper, or this one, for discussions of some of the problems with the IAT and other measures, including whether they actually measure "attitudes").ReferencesSartori, G., Agosta, S., Zogmaister, C., Ferrara, S.D., & Castiello, U. (2008). How to accurately assess autobiographical events. Psychological Science 19:772–780.Verschuere, B., Prati, V., & Houwer, J. (2009). Cheating the Lie Detector: Faking in the Autobiographical Implicit Association Test. Psychological Science DOI: 10.1111/j.1467-9280.2009.02308.x.Lie to Me - Season 1 - "Moral Waiver" - Kelli Williams as Gillian Foster and Tim Roth as Cal Lightmancourtesy Adam Taylor/Fox... Read more »

Verschuere, B., Prati, V., & Houwer, J. (2009) Cheating the Lie Detector: Faking in the Autobiographical Implicit Association Test. Psychological Science. DOI: 10.1111/j.1467-9280.2009.02308.x

March 15, 2009
12:52 AM
884 views

I Know What You Sweated Last Summer

by The Neurocritic in The Neurocritic

From the authors who first brought you "sexual sweat" (Zhou & Chen, 2008)...Be afraid... be very afraid and prepare yourself for the sequel: "FEARFUL SWEAT" (Zhou & Chen, 2009)!!!In case you didn't know that "sexual sweat" (collected from men watching porn) differs from ordinary sweat, the results of an fMRI experiment suggested that the orbitofrontal cortex and the fusiform region in 20 female participants responded differently when smelling the two substances (Zhou & Chen, 2008). However, we don't know anything specific about the unique chemical composition of sweat obtained from sexually aroused men, and why it resulted in differential brain activity in women who could not identify the odor as "sweaty/human" (see When I Get That Feeling, I Need Sexual Sweating).Nonetheless, in the present study Zhou and Chen (2009) wanted to determine the effects of another putative chemosensory signal on the perception of emotional expressions in faces. Specifically, as they explain below......we conducted two experiments focused on the effect of a fear-related chemosignal (sweat collected from donors viewing horror videos) in an emotion-identification task. We used the same type of olfactory stimuli (emotional sweat collected on gauze pads and gauze pads with no sweat) throughout, but varied the effectiveness of the visual input by varying the ambiguity of the facial emotions (from somewhat happy to ambiguous to somewhat fearful). Our manipulation of ambiguity was achieved through morphing between happy and fearful faces [as shown in Fig. 1a].Fig. 1a (Zhou & Chen, 2009). Examples of the morphed faces of two actors. For each actor, we selected seven morphs, ranging from somewhat happy to somewhat fearful. These faces were judged to be fearful 20% to 80% of the time in our pilot experiment, in the absence of any olfactory stimuli. Specifically, the Level 4 morph for each actor was the most ambiguous, judged to be fearful in the pilot study 45% to 55% of the time. And what about the olfactory stimuli obtained from the male sweat donors?On the day of each session, they wore next to their skin a new T-shirt (provided by the experimenter), to prevent odor contamination by their regular clothes. During each session, they kept a 4- x 4-in. pad (rayon-polyester blend for maximum absorbance) under each armpit while they watched each of three 20-min video segments intended to produce the emotions of fear (horror movies), happiness (slapstick comedies), and neutrality, respectively. Different videos were shown in each session. During the videos, participants’ heart rate was recorded... After watching each video, the donors rated how angry, fearful, happy, neutral, and sad they felt during the video, using a 100-mm visual analog scale. From each donor, we selected the pads worn during the 20-min videos that elicited the highest level of self-reported happy feelings and the highest level of self-reported fearful feelings. So the 48 young female subjects (mean age 19.6 years) viewed the various faces while exposed to different olfactory stimuli, and decided whether they were happy or fearful. Results indicated that on average they were significantly more likely to identify the most ambiguous morph as fearful when smelling the fearful sweat relative to the control condition (which, unfortunately, was a rayon-polyester pad with no sweat). Although the likelihood of identifying an ambiguous face as fearful did not differ between the happy sweat and control conditions, there was no direct statistical comparison between the two sweat conditions, which would seem to be a problem.adapted from Fig. 2b (Zhou & Chen, 2009). Nevertheless, there was some evidence that male horror movie sweat was able to bias the women towards viewing an ambiguous face as fearful, and this was not due to the pleasantness (or lack thereof) or intensity of the olfactory stimulus. I'd be curious to see how the "sweat of neutrality" and the "sweat of sexual arousal" [as identified by Zhou & Chen, 2008) in their earlier study] would influence emotion recognition judgments...ReferencesZhou W, Chen D. (2008). Encoding Human Sexual Chemosensory Cues in the Orbitofrontal and Fusiform Cortices. Journal of Neuroscience, 28 (53), 14416-14421.Zhou, W., & Chen, D. (2009). Fear-Related Chemosignals Modulate Recognition of Fear in Ambiguous Facial Expressions. Psychological Science, 20 (2), 177-183. DOI: 10.1111/j.1467-9280.2009.02263.xIntegrating emotional cues from different senses is critical for adaptive behavior. Much of the evidence on cross-modal perception of emotions has come from studies of vision and audition. This research has shown that an emotion signaled by one sense modulates how the same emotion is perceived in another sense, especially when the input to the latter sense is ambiguous. We tested whether olfaction causes similar sensory modulation of emotion perception. In two experiments, the chemosignal of fearful sweat biased women toward interpreting ambiguous expressions as more fearful, but had no effect when the facial emotion was more discernible. Our findings provide direct behavioral evidence that social chemosignals can communicate emotions and demonstrate that fear-related chemosignals modulate humans’ visual emotion perception in an emotion-specific way—an effect that has been hitherto unsuspected.Bonus! See sensory psychologist and olfactory specialist Avery Gilbert's take on these two studies in Basic Instinct: The Smell of Fear and Sex.TAG body spray for sick cats. "This spray is definitely not for me."... Read more »

Zhou, W., & Chen, D. (2009) Fear-Related Chemosignals Modulate Recognition of Fear in Ambiguous Facial Expressions. Psychological Science, 20(2), 177-183. DOI: 10.1111/j.1467-9280.2009.02263.x

April 25, 2008
06:02 AM
872 views

I have to praise you like I should

by The Neurocritic in The Neurocritic

OR, why most people (in Japan, at least) do give a damn about their bad reputation.MTV's Artist of the Week 04.21.08: GossipIn the burgeoning field of neurorewardspotting, the equation is pretty simple:Money = Chocolate = Sex = Fairness = Beauty = Punishing Bad Players = Alcohol = Cocaine = Nicotine = Methamphetamine = etc. AND NOW... acquiring a good reputation in the eyes of others.So add the new paper by Izuma et al. (2008) to the growing list of studies claiming that all rewards are alike (at least, as far as the striatum i... Read more »

K IZUMA, D SAITO, & N SADATO. (2008) Processing of Social and Monetary Rewards in the Human Striatum. Neuron, 58(2), 284-294. DOI: 10.1016/j.neuron.2008.03.020

Biology

February 14, 2011
07:09 PM
861 views

Posterior Hippocampus and Sexual Frequency

by The Neurocritic in The Neurocritic

Fig. 2D (Acevedo et al., 2011). Image and scatter plot illustrating greater response to the Partner (vs. a highly familiar acquaintance) in the region of the posterior hippocampus is associated with higher sexual frequency.Now there's an unexpected correlation suitable for Valentine's Day. How romantic! Actually, it is romantic because the neuroimaging study by Acevedo et al. (2011) is entitled "Neural correlates of long-term intense romantic love." How do you quantify long-term intense romantic love in an fMRI experiment?Well, what the study really examined is the brain's hemodynamic response to viewing pictures of a spouse with whom participants were still "madly in love" after an average of 21 years. Over the course of the experiment, subjects repeatedly viewed four different digital photos: Partner, Close Friend (CF), Highly Familiar "Neutral" acquaintance (HFN), and a Low-Familiar Neutral acquaintance (LFN). Specifically,The protocol implemented a block design of two 12-min sessions each consisting of six sets of four 30-s tasks in an alternating fashion, followed by stimulus ratings. Each session included two alternating images (starting image counterbalanced), interspersed with a count-back task. Duplicating procedures of Aron et al. (2005), Session 1 displayed Partner and HFN images. For the additional control comparisons, Session 2 displayed CF and LFN images. Participants were instructed to think about experiences with each stimulus person, nonsexual in nature.Yeah, it might be a problem if the participants remembered bouts of sex when they viewed their partners... Fig. 2D shows that activation in a tiny area of the left posterior hippocampus correlated with sexual frequency. The two outliers who had sex every day (or nearly every day)1 could be driving the correlation -- they certainly had a greater number of memories to choose from, and to suppress. In humans, activity in the posterior hippocampus is sensitive to the familiarity of stimuli that have behavioral relevance (Strange et al., 1999), and is associated with memory for repeated stimuli (Poppenk et al., 2010).How do Acevedo et al. (2011) interpret this correlation?Although little is known about the posterior hippocampal region [NOTE: untrue], some studies have shown increased activation in this area in association with hunger and food craving (LaBar et al., 2001; Pelchat et al., 2004), with particularly greater activity shown in obese individuals (Bragulat et al., 2010).Craving, eh? Not memory? Although the authors would like to think they controlled for familiarity with the Close Friend contrast, it seems to me nearly impossible that a co-worker, sibling, cousin, or friend could fulfill all familiarity criteria except romantic relationship. Furthermore, most of the analyses focused on comparisons between Partner vs. Highly Familiar Neutral 2 to match their previous paper (Aron et al., 2005) on the early stages of romantic love (1-17 months in duration).I could go on about the analysis methods, and whether reporting the single voxel with highest activity is appropriate [see Voodoo Correlations]. Or I could go on about the subject selection criteria: the 17 heterosexual participants (10 women, 7 men, ages 39-67 yrs, married 10-29 yrs) had an annual household income ranging from $100,000-$200,000 (perhaps not representative of the general population).But what about the main findings? Am I just being a cynic when it comes to love? It's true, some of the expected dopamine/reward areas [ventral tegmental area (VTA) and substantia nigra (SN)] showed greater activation when looking at the long-term Partner, which was very much like what was seen in the young lovers.Fig. 2A (Acevedo et al., 2011). Individuals self-reporting intense love for a long-term spouse show significant neural activation in dopamine-rich, reward regions of the VTA/SN in response to images of their partner vs a highly familiar acquaintance.Ultimately, the paper sends a positive message that in certain relationships, the exciting, obsessive, and rewarding period of intense romantic love can last for over 20 yrs, well beyond the typical and oft-cited (oprah.com)3 18 month to 3 year duration: IMPLICATIONSIndividuals in long-term romantic love showed patterns of neural activity similar to those in early-stage romantic love. These results support theories proposing that there might be mechanisms by which romantic love is sustained in some long-term relationships. For example, the self-expansion model suggests that continued expansion and novel, rewarding events with the beloved may promote increases in romantic love. Novel, rewarding experiences may use dopamine-rich systems (Schultz, 2001; Guitart-Masip et al., 2010) similar to those activated in this study.Beyond reporting relationship length (and sexual frequency), the participants filled out questionnaires including the Passionate Love Scale, the Love Attitudes Scale, the inclusion of other in the self (IOS) Scale, and the friendship-based love scale. All indicators suggested that the subjects were still "madly in love" with their partners. Did we really need neuroimaging to tell us that? Maybe...Footnotes1 The mean sexual frequency was 2.2 times a week.2 The HFN has been known about as long as the Partner, but is substantially less close than both the Partner and the Close Friend.3 If anyone can find a better reference for this than oprah.com or Tennov, D., 1979. Love and limerence. The Experience of Being in Love. Stein and Day, New York -- let me know.ReferencesAcevedo BP, Aron A, Fisher HE, & Brown LL (2011). Neural correlates of long-term intense romantic love. Social cognitive and affective neuroscience PMID: 21208991Aron A, Fisher H, Mashek DJ, St... Read more »

Acevedo BP, Aron A, Fisher HE, & Brown LL. (2011) Neural correlates of long-term intense romantic love. Social cognitive and affective neuroscience. PMID: 21208991

December 5, 2009
06:08 PM
842 views

Impaired Cognitive Empathy in Bipolar Disorder and in Patients with Ventromedial Prefrontal Lesions

by The Neurocritic in The Neurocritic

Cognitive empathy, or the ability to take another person's perspective, is closely related to (or even synonymous with) theory of mind,...the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge, etc.—to oneself and others and to understand that others have beliefs, desires and intentions that are different from one's own.On the other hand, emotional or affective empathy is "emotional contagion" - the ability to mirror an emotional response observed in another person and to experience it vicariously. Dr. Simone Shamay-Tsoory and colleagues (2009a) have developed a model that distinguishes between the two types of empathy, which are represented by separate neuroanatomical systems (see figure below).Fig. 6 (Shamay-Tsoory et al., 2009a). Two separate systems for emotional and cognitive based empathy. Behaviourally, emotional empathy involves personal distress, empathic concern and emotion recognition. Anatomically the IFG [inferior frontal gyrus] appears to be responsible for emotional empathy. ... Cognitive empathy, on the other hand, involves perspective taking, the fantasy scale and theory of mind and is mediated by the VM [ventromedial prefrontal cortex].Individuals with bipolar disorder can show deficits in social cognition and emotion regulation even in the euthymic (remitted) state (Green et al., 2007). These observation led Shamay-Tsoory et al. (2009b) to examine cognitive and emotional empathy in 19 euthymic patients with bipolar disorder and 20 matched control participants:The cognitive and affective aspects of empathic abilities were assessed using the Interpersonal Reactive Index. The Interpersonal Reactive Index includes four seven-item subscales, each tapping a different aspect of empathy: (a) the perspective taking subscale, which measures the reported tendency to adopt spontaneously the psychological point of view of others; (b) the fantasy subscale, measuring the tendency to imaginatively transpose oneself into fictional situations; (c) the empathic concern scale, measuring the tendency to experience feelings of sympathy and compassion for others; and (d) the personal distress scale assesses the tendency to experience distress and discomfort in response to others’ observed distress.The perspective-taking subscale was used as a measure of cognitive empathy, and the personal distress scale was used as a measure of emotional empathy. To assess theory of mind, the ability to detect faux pas was examined using a set of stories developed by Baron-Cohen et al. (1999). For example:James bought Richard a toy airplane for his birthday. A few months later, they were playing with it, and James accidentally dropped it. "Don't worry" said Richard, "I never liked it anyway. Someone gave it to me for my birthday."Questions after each faux pas and control passage assessed story comprehension, false belief (i.e., the speaker had a mistaken belief and not malicious intent), faux pas detection, and specific identification of the faux pas. Also tested were recognition of emotional expressions from the eyes, cognitive flexibility, and spatial planning abilities.The results indicated that the participants with bipolar disorder had lower scores than controls for cognitive empathy, but higher scores for emotional empathy.Figure 1 (Shamay-Tsoory et al. (2009b). Participant Empathy Scores.A similar effect was observed in the faux pas task, with the patients impaired on cognitive understanding, but not in affective understanding or in recognition of the faux pas. This agrees with prior studies on theory of mind in bipolar disorder (Malhi et al., 2008; Montag et al., 2009). On the other hand, the bipolar individuals showed completely intact performance on recognizing emotion in the eyes and in the spatial planning task. However, they had difficulty in set shifting and reversal learning in the cognitive flexibility task. And greater difficulty with reversal learning was associated with lower cognitive empathy scores, suggesting that cognitive inflexibility contributes to the deficiency in taking another's perspective.What does this mean?The present study results suggest that [the likelihood to engage in the process of reflecting on the viewpoint of others] is impaired in bipolar disorder. On the second affective scale, personal distress, the bipolar disorder group actually scored significantly higher than healthy comparison subjects... This indicates a greater tendency to have self-oriented feelings of anxiety and discomfort in response to tense interpersonal settings........[Their] exaggerated emotional response to others may be expressed in a dysfunctional empathic emotional overreaction (or “hyper empathy”).This notion is consistent with the “simulation” theory, according to which individuals impersonate others’ emotional mental states, using their own mental state. Thus, it may be hypothesized that bipolar disorder patients tend to engage in the “oversimulation” of others’ emotions, as reflected in high affective empathy, and as a result, they tend to misinterpret others’ mental states, which is reflected in impaired cognitive empathy and theory of mind.What are the brain systems that mediate such difficulties in those with bipolar disorder? Returning to the model in Figure 6 (above), Shamay-Tsoory et al. (2009a) associated emotional empathy with the inferior frontal gyrus (IFG) and cognitive empathy with ventromedial prefrontal cortex (VM). How did they determine such a clear dissociation? This was from another experiment that administered the same set of tests to a different population: neurological patients with fairly discrete lesions in each of those brain areas.Fig. 2 (Shamay-Tsoory et al., 2009a). Group and task (cognitive versus emotional empathy) interactions. Significant interaction between group and empathy type. Patients with VM lesions were impaired in cognitive empathy compared to the healthy controls (HC), patients with posterior lesions (PC) and patients with IFG lesions whereas patients with IFG lesions wer... Read more »

Shamay-Tsoory, S., Aharon-Peretz, J., & Perry, D. (2009) Two systems for empathy: a double dissociation between emotional and cognitive empathy in inferior frontal gyrus versus ventromedial prefrontal lesions. Brain, 132(3), 617-627. DOI: 10.1093/brain/awn279

Shamay-Tsoory, S., Harari, H., Szepsenwol, O., & Levkovitz, Y. (2009) Neuropsychological Evidence of Impaired Cognitive Empathy in Euthymic Bipolar Disorder. Journal of Neuropsychiatry, 21(1), 59-67. DOI: 10.1176/appi.neuropsych.21.1.59

March 15, 2011
05:37 AM
840 views

Exposure Therapy for Hungry Elevator Phobics

by The Neurocritic in The Neurocritic

Fun With Behavior Therapy from the 70s, Part 1In 1973, Bryntwick and Solyom published a paper on a new method of behavior therapy for elevator phobia, which involved depriving their clients of food and water for 24 hours. The rationale for their unorthodox approach was as follows:Fear habits in the animal laboratory have been diminished by first depriving the subject of food and then rewarding him with it in the fear provoking situation (Masserman, 1943; Wolpe, 1958). To apply this technique to clinical subjects has generally been considered "unthinkable". The present report illustrates the clinical effectiveness in the treatment of two elevator phobic subjects.Apparently, both of the patients voluntarily agreed to forgo eating and drinking for one day. Here is the background information on the two elevator phobic subjects, one of whom had good reason to be phobic (in my view):Mr. B.M., a 32-yr-old businessman, had suffered from an elevator phobia for about 5 yr. He attributed his fear to two occasions within a 2-week period when he was trapped in an elevator for a few minutes. Since then he would climb 16 floors rather than take an elevator. Several times daily he climbed three flights of stairs to his office. On a 0-4 point scale, he rated his fear of elevators as 4, corresponding to "terrifying panic attacks if avoidance impossible". No other obvious psychopathology was apparent...Mr. W.H., a 19-yr-old student, had suffered from travel and claustrophobia for approximately 3 yr. He was markedly obsessive, being very orderly, meticulous and hesitant, with a tendency to ruminate. One manifestation of his claustrophobia was avoidance of elevators. He also rated his elevator phobia at 4...As for treatment, both patients had failed "aversion relief therapy" for elevator phobia, so the authors found it appropriate to use feeding as a counter-conditioner in vivo.Each patient, after agreeing to the new procedure, was instructed not to eat or drink for 24 hr prior to the treatment session. After that deprivation the patient was led to an elevator where he found a table attractively arranged with his most preferred foods. For the next 35 rain he sat eating his dinner while the elevator moved up and down. At the end of the session, the patient was encouraged to take self-service elevators in as many different buildings as possible.Both patients reported minimal anxiety and for the first time did not avoid taking elevators.Possible scenario for the elevator exposure dining experience.Unfortunately, Mr. W.H. had a relapse after being the victim of a cruel prank:One week after the first session, however, Mr. W.H. was riding in an elevator when the building superintendent, also in the elevator, stopped it with the comment, "I wonder if it will start again". Although the elevator was stopped for only 5 sec, Mr. W.H.'s anxiety rose to its original intensity.No matter, all was not lost. Two weeks later a booster session eliminated his elevator phobia once again. Both patients were reportedly "phobia free" two years later.Not everyone in the behavior therapy community was pleased with this approach, however. Rosen and Orenstein (1974) were quite critical of the treatment, and nearly called the food deprivation aspect a farce:...There appears to be no evidence to support the position that such deprivation significantly adds to the effectiveness of a treatment program based on in vivo exposure alone. The first author’s own experience with an “elevator phobic” suggests that avoidance of elevators can be eliminated in a single in vivo session without recourse to theoretical “counter-conditioners”. The client spent 45 min riding in the elevator of an eight story building sometimes accompanied by the therapist and sometimes on her own. During the session there were large reductions in her self-reported anxiety. Four days later the client rode in the same elevator on her own. She has since ridden in other elevators demonstrating what could be called a “generalization of treatment effects”. This particular patient missed out on the elevator fine dining experience, though...ReferencesBryntwick, S. & Solyom, L. (1973). A brief treatment of elevator phobia. Journal of Behavior Therapy and Experimental Psychiatry, 4 (4), 355-356 DOI: 10.1016/0005-7916(73)90008-6Rosen, G. & Orenstein, H. (1974). A critical comment on the use of food deprivation in the “Brief treatment of elevator phobia”. Journal of Behavior Therapy and Experimental Psychiatry, 5 (3-4) DOI: 10.1016/0005-7916(74)90087-1Elevator - What Could Possibly Go Wrong?

... Read more »

Bryntwick, S. (1973) A brief treatment of elevator phobia. Journal of Behavior Therapy and Experimental Psychiatry, 4(4), 355-356. DOI: 10.1016/0005-7916(73)90008-6

Rosen, G. (1974) A critical comment on the use of food deprivation in the “Brief treatment of elevator phobia”. Journal of Behavior Therapy and Experimental Psychiatry, 5(3-4), 313. DOI: 10.1016/0005-7916(74)90087-1

June 28, 2011
06:16 PM
834 views

JAMA on 60s Psychedelic Drug Culture

by The Neurocritic in The Neurocritic

An amusing semi-anthropological study was published in JAMA by Ludwig and Levine in 1965. It was based on extensive interviews with 27 "postnarcotic drug addict inpatients" who were treated at a hospital in Lexington, Kentucky. The specific drugs of interest included peyote (from the peyotl cactus plant), mescaline, LSD, and psilocybin. The current availability of each drug, most popular methods of intake, slang terms, psychoactive properties, and subcultural norms were discussed. Hallucinogens were sometimes combined with narcotics, barbituates, amphetamines, or marijuana, depending on the specific demographic group. Basically, there were the junkies, the potheads, and the psychonauts:There appear to be three main patterns of hallucinogenic drug use. First, there are the people who are primarily and preferentially narcotic drug addicts who have used the hallucinogenic agents on one or several occasions mainly for "kicks" or "curiosity." They seldom seek these drugs and tend to use them infrequently, as for example when these agents come their way through a friend or at a party. Rarely do they take the hallucinogenic agent alone but tend to take it after a "fix" with heroin, hydromorphone hydrochloride, morphine, or some other narcotic drug to which they are addicted at the time.The next group sounds like your everyday 1960s hippie stereotype:Second, there are the group of people, aptly described by one of the informants as the "professional potheads," who have had extensive experience with various drugs. The most commonly used drug by this group of people is marijuana (hence the name "potheads"), but amphetamines and barbiturates are also popular. Many have had some experience with the narcotic drugs, but on the whole they tend to avoid the opiates. "Creative" and "arty" people, such as struggling actors, musicians, artists, writers, as well as the Greenwich Village type of "beatnik," tend to fall in this category. The "frustrated," "curious," "free thinkers," "nonconformists," and "young rebels," who are seeking a temporary escape also comprise this class of hallucinogenic users, according to our informants. Although the "professional potheads" enjoy the euphoric effects produced by smoking marijuana, they also tend to relish and seek out the feelings of greater insight, inspiration, and sensory stimulation and distortions which the hallucinogens may produce. They are in constant search of agents to rouse them from their apathy, to make life more meaningful, to overcome social inhibitions, and to facilitate meaningful conversations and interpersonal relationships.Especially enjoyable was the description of the drug parties frequented by these types:Hallucinogenic agents are used by these people mainly on weekends (often "four-day weekends") or on special occasions, such as parties. It is rare for users to take drugs alone. They are mainly taken with friends or at intimate gatherings of people. The parties are of all varieties. Frequently, little conversation takes place while people are under the influence of these drugs, but they claim to experience a greater closeness and rapport with the other members of the group. One patient described having attended "basket weaving" and "lampshade making" parties where all members, under the influence of these drugs, squatted on the floor and silently attended to their tasks. At another type of party, overt sexual activities were carried out. Folk singing was also common. To quote another patient, "Mostly the people sit around trying to dig each other . . . everybody is sitting around and waiting, like on New Year's Eve, for something to happen."Finally were a small number of hard core exclusive users of hallucinogens in search of an expanded consciousness, whether it be religious, spiritual, or cosmic:Third, there are a small number of people who take the hallucinogenic agents repeatedly over a sustained period of time to the exclusion of all other drugs. The frequency of drug use during these periods of time is variable. One patient took peyote four times a day over a two-year period, while another patient took it two out of every three days over a three-month period. One patient took mescaline every day for two separate 15-day periods, while another took mescaline every two to three days over a six-month period...Generally, these patients seemed different from those in the second group, who primarily smoke marijuana. They did not take these drugs in a group for social purposes but used them mainly as a means of attaining some personal, esoteric goal. One patient talked of having achieved an increased sensitivity to nature and a greater insight into himself after prolonged peyote usage. While living by himself on Big Sur in California, he claimed to have achieved a "Christ-like state of mind" and a greater feeling of altruism. Another patient stated that as he kept taking mescaline, he was able to control his experience and attained a state of mind in which "every little thing is projected large," where he was able to see the negative and positive aspects of everything, and where "everything is real." A third patient, of Mexican extraction, kept taking peyote to "find God."In the last several months, there have been a spate of articles on the return of psychedelics for psychotherapeutic purposes. Maia Szalavitz has covered some of the most recent developments: 'Magic Mushrooms' Can Improve Psychological Health Long Term and A Mystery Partly Solved: How the 'Club Drug' Ketamine Lifts Depression So Quickly.Last year, a Neurocritic post (Ketamine for Depression: Yay or Neigh?) was part of a Nature Blog Focus on hallucinogenic drugs in medicine and mental health, inspired by the Nature Reviews Neuroscience paper, The neurobiology of psychedelic drugs: implications for the treatment of mood disorders, by Franz Vollenweider & Michael Kometer. For more information on this Blog Focus, see the Table of Contents.The secret history of psychedelic psychiatry was discussed over at Neurophilosophy. Neuroskeptic covered ... Read more »

LUDWIG AM, & LEVINE J. (1965) PATTERNS OF HALLUCINOGENIC DRUG ABUSE. JAMA : the journal of the American Medical Association, 92-6. PMID: 14233246

May 14, 2009
08:40 PM
829 views

Suicide Rates in Greenland Are Highest During the Summer

by The Neurocritic in The Neurocritic

by: crdagainSeasonal affective disorder (SAD) is a cyclical depressive disorder that typically recurs every year during the shorter days and longer nights of late fall-early winter. Much of the research on SAD has focused on changes in the photoperiod and the accompanying effects on circadian rhythms during winter. So it might come as a surprise that in Greenland, the suicide rate peaks during the summer months of continuous sun (especially at the highest latitudes). However, the rate of homicides and the sales of beer do not show the same seasonal variation (Björkstén et al., 2009). Why might this be? Most suicides in Greenland are of the impulsive variety and are committed using violent methods. The authors' previous work observed the summer suicide spike (Björkstén et al., 2005), and now they wanted to determine whether homicides show the same seasonal pattern. They reviewed the evidence on serotonin, impulsivity, and violence, and hypothesized that altered serotonin turnover might be a common factor in both violent suicides and violent homicides (reasoning that increased serotonin turnover in spring and summer might enhance impulsiveness and aggression).How was this assessed? Northern Greenland (obviously) shows the greatest seasonal extremes in the amount of light and darkness. The country maintains good statistics, and the Inuit population is considered to be relatively homogeneous. Thus, Björkstén, Kripke, and Bjerregaard (2009) examined computerized records listing the causes of all deaths in Greenland during the time period of 1968-2002. To determine whether alcohol consumption played a role in the rates of suicides and murders, the pattern of beer purchases at a major chain store from July 2005 to June 2006 were used as a proxy ("Detailed sales data are secret for business reasons").The authors note some extremely tragic statistics:The suicide rate in Greenland increased during the 1970’s from a historically very low level to one of the highest levels in the world, 107 per 100,000 person-years in 1990-1994. The increase has been most pronounced among teenagers and young adults. A rapidly increasing suicide rate has been reported from other areas going through radical changes like in Eastern Europe after the fall of communism and among aboriginal people confronted with modern lifestyle.We have previously demonstrated that the vast majority of suicides in West Greenland are violent and peak in the summer when the Northern half of Greenland has constant day-light and the Southern half has extremely long days. Depression has, however, been reported uncommon and the majority of suicides seem impulsive rather than depressive.The overall homicide rate in Greenland has been reported much higher than that of the other Nordic countries. Homicides are almost exclusively impulsive and committed under the influence of alcohol...Continuing in a depressing vein, there were 1351 suicides (80.5 % were men) and 308 homicides during the 35 year period under study.Persons in upper teens and young adults were heavily over-represented among the suicide cases. Median age was 25 years...In 391 out of the 1351 cases (29%), the death certificate included a psychiatric diagnosis. In 214 cases (15.8%), there was a diagnosis of alcoholism or alcohol intoxication; two cases also had a diagnosis of psychosis. In only 52 cases (3.8%), there was a diagnosis of affective disorder, either unspecified or in the depressive state. In 104 cases, there was a diagnosis of psychosis. In addition to the 104 cases (7.7%), there were two with alcoholism and psychosis.However, affective disorders could have been underdiagnosed in the population... we don't really know for sure. What we do know is that violent methods of suicide were used in 95% of all cases (n=1286), with men using violent methods 97% of the time and women 86% of the time (the latter percentage in stark contrast to the general population outside of Greenland). Figure 3a below shows the seasonal variation in all suicide cases. The annual peak occurred on June 11th and the trough in November-January, and the effect of seasonality was significant (p... Read more »

Bjorksten, K., Kripke, D., & Bjerregaard, P. (2009) Accentuation of suicides but not homicides with rising latitudes of Greenland in the sunny months. BMC Psychiatry, 9(1), 20. DOI: 10.1186/1471-244X-9-20

June 19, 2008
05:01 AM
823 views

Mirror Neurons Control Hard-ons?

by The Neurocritic in The Neurocritic

from MR BEAN IN TOILETEveryone knows that mirror neurons control the universe. Now, a study by Mourus and colleagues supposedly tells us that mirror neurons control the most important thing in the universe!Mirror neurons control erection response to porn14:15 16 June 2008NewScientist.com news serviceAlison Motluk. . .Harold Mouras, at University of Picardie Jules Verne in Amiens, France, and his colleagues wanted to understand the cerebral underpinnings of visually-induced erections.They suspected there might be a role for mi... Read more »

H MOURAS, S STOLERU, V MOULIER, M PELEGRINIISSAC, R ROUXEL, B GRANDJEAN, D GLUTRON, & J BITTOUN. (2008) Activation of mirror-neuron system by erotic video clips predicts degree of induced erection: an fMRI study. NeuroImage. DOI: 10.1016/j.neuroimage.2008.05.051

Biology

March 30, 2011
08:47 AM
823 views

Simon Baron-Cohen, Empathy, and the Atrocities in Afghanistan

by The Neurocritic in The Neurocritic

From Rolling Stone MagazineAn excerpt from Simon-Baron Cohen's new book, Zero Degrees of Empathy: a New Theory of Human Cruelty, appeared as The science of empathy in the Guardian. Overall, the writing revealed him to be unempathetic in some respects, particularly with regard to people with borderline personality disorder1 (BPD):Unempathic acts are simply the tail end of a bell curve, found in every population on the planet. If we want to replace the term "evil" with the term "empathy", we have to understand empathy closely. The key idea is that we all lie somewhere on an empathy spectrum. People said to be "evil" or cruel are simply at one extreme of the empathy spectrum. We can all be lined up along this spectrum of individual differences, based on how much empathy we have. At one end of this spectrum we find "zero degrees of empathy".. . .Zero degrees of empathy does not strike at random in the population. There are at least three well-defined routes to getting to this end-point: borderline, psychopathic, and borderline personality disorders. I group these as zero-negative because they have nothing positive to recommend them. They are unequivocally bad for the sufferer and for those around them. Of course these are not all the sub-types that exist. Indeed, alcohol, fatigue and depression are just a few examples of states that can temporarily reduce one's empathy, and schizophrenia is another example of a medical condition that can reduce one's empathy.This comes after an introduction that recounts a childhood memory: when his father told him that the Nazis turned Jewish people into lampshades and soap. So people with BPD are "evil", "zero-negative" and have "zero degrees of empathy" (similar to the Nazis). This is quite a stunning characterization, in fact one that is not borne out by the literature. For example, one study showed that individuals with BPD are actually better than controls on a test of empathy designed by Baron-Cohen himself (Fertuck et al., 2009).2 That would be the Reading the Mind in the Eyes Test (RMET), "a measure of the capacity to discriminate the mental state of others from expressions in the eye region of the face." The study showed that:The BPD group performed significantly better than the HC group on the RMET, particularly for the Total Score and Neutral emotional valences. Effect sizes were in the large range for the Total Score and for Neutral RMET performance. The results could not be accounted for by demographics, co-occurring Axis I or II conditions, medication status, abuse history, or emotional state. However, depression severity partially mediated the relationship between RMET and BPD status.The authors concluded that this enhancement of facial emotion recognition abilities (or "enhanced sensitivity to the mental states of others") is what can get BPD persons in trouble socially. Consistent with this finding, another study found a double dissociation between two different types of empathy in BPD (Harari et al., 2010). Emotional empathy was slightly enhanced, whereas cognitive empathy was significantly impaired relative to controls.Fig. 1 (Preißler et al., 2010). (A) a significant group-by-type (interaction) effect [F(1,40) = 6.375, P = 0.016]. The HC group had significantly higher scores (*) in the cognitive empathy scale, whereas there was an opposite trend is observed in the BPD group. Cognitive empathy, or the ability to take another person's perspective, is closely related to (or even synonymous with) theory of mind. On the other hand, emotional or affective empathy is "emotional contagion" - the ability to mirror an emotional response observed in another person and to experience it vicariously. The literature on emotional empathy in BPD isn't entirely consistent, however. Although Preißler and colleagues (2010) reported preserved (but not enhanced) performance on the RMET, they observed an impairment on the “Movie for the Assessment of Social Cognition” (MASC) in the BPD participants.In his book, Baron-Cohen also provides a case study from another population with "zero degrees of empathy" -- the psychopath:Paul's career of criminal behaviour had begun when he was as young as 13, when he had set fire to the school gym and sat in a tree across a field to watch it burn. He was expelled and from there went to three more schools, each time being expelled for aggression – starting fights in the playground, attacking a teacher who asked him to be quiet and even jumping on someone's head when they wouldn't let him join the football team.Paul [currently in jail for murder] is clearly not the kind of guy you want to live near. Many would not hesitate to describe him as "evil". He is a psychopath – a Type P – though to give him the proper diagnostic label, he has antisocial personality disorder. He earns this label because he shows "a pervasive pattern of disregard for and violation of the rights of others that begins in childhood or adolescence, and continues into adulthood".This sounds similar to the description of Cpl. Jeremy Morlock in The Kill Team, a recent article in Rolling Stone on the American soldiers in Afghanistan who killed innocent civilians and mutilated their corpses. [NOTE: I am not linking directly to this article because it contains very graphic and disturbing photographs. You'll find them within the online magazine if you want to see them.] According to Rolling Stone:Before the military found itself short of troops in Afghanistan and Iraq, Morlock was the kind of bad-news kid who the Army might have passed on. He grew up not far from Sarah Palin in Wasilla, Alaska; his sister hung out with Bristol, and Morlock played hockey against Track. Back in those days, it seemed like he was constantly in trouble: getting drunk and into fights, driving without a license, leaving the scene of a serious car accident.But it gets worse and escalates, just like with Paul: he committed the serious crime of spousal abuse only one month before being deployed. Unfortunately, he was only charged with "disorderly conduct" and then sent off to Afghanistan anyway:Even after he joined the Army, Morlock continued to get into trouble. In 2009, a month before he deployed to Afghanistan, he was charged with disorderly conduct after burning his wife with a cigarette. After h... Read more »

Fertuck, E., Jekal, A., Song, I., Wyman, B., Morris, M., Wilson, S., Brodsky, B., & Stanley, B. (2009) Enhanced ‘Reading the Mind in the Eyes’ in borderline personality disorder compared to healthy controls. Psychological Medicine, 39(12), 1979. DOI: 10.1017/S003329170900600X

Harari, H., Shamay-Tsoory, S., Ravid, M., & Levkovitz, Y. (2010) Double dissociation between cognitive and affective empathy in borderline personality disorder. Psychiatry Research, 175(3), 277-279. DOI: 10.1016/j.psychres.2009.03.002

April 24, 2009
04:44 PM
821 views

"All I need is a TV show..."

by The Neurocritic in The Neurocritic

A Warm TV Can Drive Away Feelings of Loneliness & RejectionStudies find that illusionary relationships with TV characters can give us real pleasureRelease Date: April 22, 2009BUFFALO, N.Y. -- Not all technology meets human needs, and some technologies provide only the illusion of having met your needs.But new research by psychologists at the University at Buffalo and Miami University, Ohio, indicates that illusionary relationships with the characters and personalities on favorite TV shows can provide people with feelings of belonging, even in the face of low self esteem or after being rejected by friends or family members.The findings are described in four studies published in the current issue of the Journal of Experimental Social Psychology [Derrick et al., 2009].However, after some sleuthing to uncover the classical literature on the topic, I've discovered that Rutherford et al. (1980) described this phenomenon nearly 30 years ago:You're just another face that I know from the TV showI have known you for so very long I feel you like a friendCan't you do anything for me, can I touch you for a whileCan I meet you on another day and we will fly awayTurn It On Again ------Rutherford et al. 1980Derrick et al., 2009 replicated this finding in a series of four experiments, all of which supported the Social Surrogacy Hypothesis, i.e.,...that parasocial relationships provided by television programs can yield the experience of belonging. Specifically, we drew three primary predictions from the Social Surrogacy Hypothesis. If favorite television programs can yield the experience of belonging, we hypothesized that (1) events that typically elicit belongingness needs (e.g., threats to a relationship, a rejection experience) would elicit a desire to experience a favored television program, (2) thinking about a favored television program could buffer against threats to real-world belongingness, and (3) thinking about a favored television program should reduce the accessibility of loneliness related concepts.In Study 1, 701 college students completed the lonely activities scale and the likelihood of feeling lonely scale. These scales were developed for the current study by asking 12 other undergraduates to list non-social activities that people might do when they feel lonely. A final list of 31 activities was given to the larger group, who were asked to rate the items on a scale of 1 (would definitely not do) to 7 (definitely would do). The top six items were:Listen to music – a particular CD/tapeWatch television – a favorite TV programSleepSurf the webEatExerciseParticipants were also asked to rate their likeliness of feeling lonely when doing these activities, on the same 7 point scale. And not surprisingly (since we already know that all of the experiments supported the hypothesis), people felt significantly less lonely when watching TV.Of course, this result was only correlational in nature, so Study 2 manipulated "belongingness needs". Half of the participants were asked to write an essay about a fight with a close other, and the other half were asked to list as many items at home as they could remember. I would have suggested a better neutral essay-writing condition than the residental list, along with a condition to deliberately reduce "belongingness needs" (like an essay about an enjoyable shared experience with a close other). But then again, I'm not a social psychologist, so what do I know?After the first writing exercise, subjects were asked to write another essay about watching either a favorite show, or whatever was on at the time.Participants in the Favored condition wrote about a time they watched their favorite television program, describing it in as much detail as possible. Participants in the Control condition wrote about a time when they had watched “whatever was on” television, describing it in as much detail as possible. Participants were asked to describe as much as they could about the content of the program and their experience watching it. Length of time writing this Parasocial essay served as the primary dependent measure.Lo and behold, the predicted Belongingness Needs × Parasocial Essay interaction was obtained:Fig. 1 (Derrick et al., 2009). Length of time spent writing television essay as a function of social needs condition and type of television program.Study 3 was nearly identical to Study 2, except the Parasocial Essay component was limited to 6 min, and the dependent measures were self-esteem, mood, and feelings of rejection. Again, the predicted Belongingness Needs × Parasocial Essay interactions were obtained for state self-esteem, mood, and a trend for feelings of rejection.Now the authors need to extend these findings to actually watching a favorite vs. a random TV show, instead of just thinking about watching.See also:TV Relieves LonelinessDoes Your TV Give You the Warm Fuzzies?ReferencesDerrick, J., Gabriel, S., & Hugenberg, K. (2009). Social surrogacy: How favored television programs provide the experience of belonging. Journal of Experimental Social Psychology, 45 (2), 352-362. DOI: 10.1016/j.jesp.2008.12.003Rutherford M, Collins P, Banks T. (1980). Turn It On Again. Duke.All I need is a TV show, that and the radioDown on my luck again, down on my luck againI can show you I can show you some of the people in my lifeI can show you I can show you some of the people in my lifeIt's driving me mad just another way of passing the dayI, I get so lonely when she's not thereTurn It On Again ------Rutherford et al. 1980... Read more »

Derrick, J., Gabriel, S., & Hugenberg, K. (2009) Social surrogacy: How favored television programs provide the experience of belonging. Journal of Experimental Social Psychology, 45(2), 352-362. DOI: 10.1016/j.jesp.2008.12.003

May 10, 2012
08:22 AM
819 views

Spindle Neurons in Macaques?

by The Neurocritic in The Neurocritic

Spindle neurons, or Von Economo neurons (VENs), are a unique type of large, bipolar neuron found primarily in layer Vb in the anterior cingulate cortex and the frontoinsular cortex of humans.1 In 1999, Nimchinsky and colleagues discovered that among the 28 nonhuman primate species they examined, only great apes had VENs [see Spindle Neurons: The Next New Thing?].Spindle neurons are also seen in humpback, fin, sperm, and killer whales (Hof & Van der Gucht, 2007), elephants (Hakeem et al., 2009), and cetaceans such as the bottlenose dolphin, Risso’s dolphin, and the beluga whale (Butti et al., 2009).Because VENs are only found in large-brained, highly evolved social species, and are potentially implicated in certain neurological and psychiatric disorders, their hypothesized functions include empathy, conscious awareness, and self-referential processing. A 2011 review by Allman and colleagues reiterated that only great apes (bonobos, chimpanzees, gorillas, orangutans) have VENs and suggested they......may be a specialization related to very large brain size. The large size and simple dendritic structure of these projection neurons suggest that they rapidly send basic information from FI [frontoinsular cortex] and LA [limbic anterior area] to other parts of the brain, while slower neighboring pyramids send more detailed information. Selective destruction of VENs in early stages of frontotemporal dementia (FTD) implies that they are involved in empathy, social awareness, and self-control, consistent with evidence from functional imaging.VENs: Not Only for Great Apes Any More!But now, a new study has identified these special neurons in the insular cortex of macaque monkeys (Evrard et al., 2012).Figure 1 (Evrard et al., 2012). The Von Economo Neuron Is Present in Layer 5b in a Restricted Portion of the Agranular Anterior Insula in the Macaque Monkey (A) High-magnification photomicrographs demonstrating the identical morphology of the macaque and human VENs. Scale bar represents 25 μm.Why weren't they found in the earlier studies that looked for them?Three reasons: (1) they're a lot smaller in monkeys; (2) they're more fragile in monkeys; and (3) they're confined to a more limited anatomical region.First, the large human VENs unambiguously stand out at low microscope magnifications. Searching for relatively smaller VENs among the densely packed cell population in layer 5 in the monkey required the highest microscope magnification, which would be unusual for anyone accustomed to examining the more obvious VENs in hominids. Second, the cytoskeletal matrix of the small monkey VENs might be more fragile during histological processing than that of the larger human VENs. ... Third, in the major prior study, the number of VENs in humans and great apes was counted in consecutive sections that were apparently spaced at 1 mm intervals ... such a sampling paradigm would likely have been inadequate for the identification of VENs within the small VEN-containing region of the ventral AAI that measures ∼2 × 2 × 1 mm3 in macaques.The authors pointed out a major advantage of their new discovery, namely that more invasive studies are now possible (i.e., you can't do single cell neurophysiology in dolphins or bonobos).But wait... are they really VENs?The morphology, size, laminar distribution, and proportional distribution of the monkey VEN suggest that it is at least a primal anatomical homolog of the human VEN. Allman, Hof, and colleagues might have something more to say on the matter, based on their earlier findings (e.g., Allman et al., 2011):The VENs are illustrated at higher magnification in Figure 3, which shows that they have very similar morphology in the great apes and humans. In primates, the VENs are present in FI only in great apes and humans. This is the same taxonomic distribution as was found for the VENs in LA, which suggests that the VENs emerged as a specialized neuron type in the common ancestor of great apes and humans. Figure 3 (Allman et al., 2011). VENs in area FI of humans and great apes.The new paper concedes that:The presence of VENs in the macaque does not discredit prior evidence for a crucial role of the VENs and AIC in the emergence of self-awareness and social cognition in humans (Craig, 2009; Allman et al., 2011). VENs in humans appear to be disproportionally slightly larger than in macaques (see above); they may also have an enhanced immunopositivity (and perhaps gene expression) for proteins that are typically involved in homeostasis, which perhaps favors higher interoceptive sensitivity. Are they confined to the anterior insula in macaques? No, VENs were also found in the ACC, but that will be reported separately (a lesson for all you junior scientists).Now that they've been found in monkeys [and can be studied physiologically], will spindle neurons finally catch up with their more glamorous elder cousins, the mirror neurons? Are they really the next new thing? Six years ago, I pondered these points:Somehow, the "spindle neuron" meme hasn't caught on like the "mirror neuron" meme. Is it because spindle neurons have been only been described anatomically (not physiologically), while the reverse is true for mirror neurons? Anatomically speaking, do we know much about mirror neurons? Evrard, Forro, and Logothetis are all over it:...invasive studies of their organization, hodology, and physiology could provide significant insights into the evolutionary basis for self-awareness and empathy in humans. Regarding the latter, it would be particularly interesting to examine whether the VENs share functional similarities with the “mirror” neurons of the ventral premotor cortex (Gallese et al., 2004).Finally, a commentary in Neuron by Critchley and Seth (2012) wonders if studies of the macaque insula will reveal the neural mechanisms of self-referen... Read more »

Butti, C., Sherwood, C., Hakeem, A., Allman, J., & Hof, P. (2009) Total number and volume of Von Economo neurons in the cerebral cortex of cetaceans. The Journal of Comparative Neurology, 515(2), 243-259. DOI: 10.1002/cne.22055

Evrard, H., Forro, T., & Logothetis, N. (2012) Von Economo Neurons in the Anterior Insula of the Macaque Monkey. Neuron, 74(3), 482-489. DOI: 10.1016/j.neuron.2012.03.003

July 27, 2008
12:19 AM
818 views

The Neural Correlates of Compulsive Hoarding

by The Neurocritic in The Neurocritic

The previous two posts described the emergence of compulsive collecting behavior (of Toy Bullets and Televisions) following damage to the orbitofrontal cortex. Although these unusual case reports do appear in the neurological literature, compulsive hoarding or collecting is much more common in psychiatric settings, as a disorder that may occur as a symptom of OCD (or as a separate diagnosis). In fact, in their new paper, Pertusa and colleagues (2008) ask the question, Compulsive Hoarding: OCD Symptom, Distinct Clinical Syndrome, or Both? [Both1]. Earlier studies have come to similar conclusions (e.g., Grisham et al., 2005).A recent neuroimaging study (An et al., 2008) used a symptom provocation procedure to examine the neural correlates of hoarding. The research participants were restricted to individuals with obsessive-compulsive disorder; those hoarders without an OCD diagnosis were excluded. Thus, two groups of OCD patients (those with and without hoarding symptoms) were compared to demographically matched controls while viewing three types of pictures [the figure is my completely fabricated rendition of possible exemplars2].(1) neutral or mildly positive - 150 color pictures rated as low in disgust and anxiety. Examples included furniture, nature scenes, urban landscapes, household items, pets, families. The pictures were obtained from the International Affective Picture System.(2) aversive control - 50 color pictures of scenes rated as highly disgusting and anxiety-provoking by healthy subjects were also obtained from the IAPS. These included scenes of mutilated bodies/wounds, small animals (snakes, spiders, cockroaches and rats) and body products.(3) commonly hoarded objects - 50 color pictures that included items such as old magazines/newspapers, empty food containers, clothes and toys. These pictures were rated by several patients (not in the fMRI study) to ensure that they would be anxiety-provoking.The pictures were presented in alternating blocks of neutral and emotional. Participants were instructed toimagine being in a particular situation while looking at the scenes they were about to see (for example, for hoarding: ‘Imagine that these objects belong to you and that you must throw them away forever;’ for aversive control: ‘Imagine that you must come into contact with what is shown in the pictures’). After each set of pictures were presented, another prerecorded sound file of the question ‘How anxious do you feel?’ was played and the subjects rated their subjective anxiety on a Likert-style scale (0 = no anxiety to 8 = extreme anxiety).Not surprisingly, the OCD-hoarders rated the hoarding pictures as more anxiety-provoking than did the other two groups. However, the aversive control pictures were rated as equivalently yucky by all three groups.What did the fMRI results show? From the previous neurological case studies, one would expect differences in the orbitofrontal cortex of the OCD-hoarding group, relative to the non-hoarding and control participants. And indeed, when viewing the provocative stacks of magazines and empty food containers,OCD patients with prominent hoarding symptoms showed greater activation in bilateral anterior ventromedial prefrontal cortex (VMPFC) than patients without hoarding symptoms and healthy controls.Figure 2A (An et al., 2008). Brain regions significantly more activated in hoarders than in non-hoarders and controls (shown in red) during symptom provocation. The functional data are superimposed on a high-resolution anatomical template using the MRIcro software. The left side of the brain appears on the right side of the image. The box plots depict the percent change in blood oxygen level dependent (BOLD) response in each group. In each box plot, the horizontal lines represent the group median, the box represents the quartiles and the whiskers the extreme values in each group.In contrast, when comparing the disgusting aversive pictures to neutral pictures, the activated regions in the hoarding OCD patients were more similar to those that were seen in the non-hoarding OCD patients and the healthy control participants. However, the hoarders did show less activation in the cerebellum and visual areas than the controls (and the non-hoarders showed more).The authors suggest thatThe brain regions associated with compulsive hoarding in this study are anatomically very close to those associated with hoarding behaviors ... in human lesion studies. Although it is plausible that hoarding behaviors caused by brain lesions may be phenomenologically and etiologically distinct from obsessive-compulsive hoarding, our results seem to suggest that they share similar neural substrates. [Although the regions are missing in the human lesion patients, and overactive in the OCD hoarding patients...]For more information on compulsive hoarding:The Anxiety Disorders Center at Hartford Hospital - Compulsive HoardingDepartment of Psychiatry, UCSD - WHAT IS COMPULSIVE HOARDING?Understanding Compulsive Hoarding - from the Children of Compulsive Hoarders website, which features a wealth of information, videos, and support for families.Several months ago, Mind Hacks reviewed the short documentary film, Possessed, which is about four people with compulsive hoarding disorder. The filmmaker, Martin Hampton, is currently working on a follow-up project about people's personal experiences with OCD.News stories:New York Times - A Clutter Too Deep for Mere Bins and ShelvesABC News - The Tortured Lives of People Who Can't Throw Things OutDiscover magazine - The Psychology of . . . HoardingFootnotes1 Both, say Pertusa et al.:Overall, the phenomenology of hoarding behavior was similar in the two hoarding groups [OCD with Hoarding, Hoarding only]. The majority of participants in both groups reported hoarding common items as a result of their emotional and/or intrinsic value. However, approximately one-fourth of participants in the compulsive hoarding with OCD group showed a different psychopathological profile, which was characterized by the hoarding of bizarre items and the presence of other obsessions and compulsions related to their hoarding, such as fear of catastrophic consequences, the need to perform checking rituals, and the need to perform mental compulsions before discarding any item. ... In most individuals, compulsive hoarding appears to be a syndrome separate from OCD, which is associated with substantial levels of disability and social isolation. However, in other individuals, compulsive hoarding may be considered a symptom of OCD and has unique clinical features.2 I decided to use a moldy slice of bread, rather than a mutilated body part, so as not to offend the sensibilities of the more delicate reader.ReferencesAn SK, Mataix-Cols D, Lawrence NS, Wooderson S, Giampietro V, Speckens A, Brammer MJ, Phillips ML (2008). To discard or not to discard: the neural basis of hoarding symptoms in obsessive-compulsive disorder. Molecular Psychiatry DOI: 10.1038/sj.mp.4002129Preliminary neuroimaging studies suggest that patients with the 'compulsive hoarding syndrome' may be a neurobiologically distinct variant of obsessive-compulsive disorder (OCD) but further research is needed. A total of 29 OCD patients (13 with and 16 without prominent hoarding symptoms) and 21 healthy controls of both sexes participated in two functional magnetic resonance imaging experiments consisting of the provocation of hoarding-related and symptom-unrelated (aversive control) anxiety. In response to the hoarding-related (but not symptom-unrelated) anxiety provocation, OCD patients with prominent hoarding symptoms showed greater activation in bilateral anterior ventromedial prefrontal cortex (VMPFC) than patients without hoarding symptoms and healthy controls. In the entire patient group (n=29), provoked anxiety was positively correlated with activation in a frontolimbic network that included the anterior VMPFC, medial temporal structures, thalamus and sensorimotor cortex. Negative correlations were observed in the left dorsal anterior cingulate gyrus, bilateral temporal cortex, bilateral dorsolateral/medial prefrontal regions, basal ganglia and parieto-occipital regions. These results were independent from the effects of age, sex, level of education, state anxiety, depression, comorbidity and use of medication. The findings are consistent with the animal and lesion literature and several landmark clinical features of compulsive hoarding, particularly decision-making difficulties. Whether the results are generalizable to hoarders who do not meet criteria for OCD remains to be investigated.Grisham JR, Brown TA, Liverant GI, Campbell-Sills L. (2005). The distinctiveness of compulsive hoarding from obsessive-compulsive disorder. J Anxiety Disord. 19:767-79.Pertusa A, Fullana MA, Singh S, Alonso P, Menchón JM, Mataix-Cols D. (2008). Compulsive Hoarding: OCD Symptom, Distinct Clinical Syndrome, or Both? Am J Psychiatry. May 15. [Epub ahead of print].... Read more »

S An, D Mataix-Cols, N S Lawrence, S Wooderson, V Giampietro, A Speckens, M J Brammer, & M L Phillips. (2008) To discard or not to discard: the neural basis of hoarding symptoms in obsessive-compulsive disorder. Molecular Psychiatry. DOI: 10.1038/sj.mp.4002129

Biology

December 30, 2008
12:15 AM
804 views

Deal, No Deal, or Dots?

by The Neurocritic in The Neurocritic

OR: Is Perceptual Decision Making in Primate LIP Equivalent to Financial Decision Making Under Risk?In the universally familiar game show Deal or No Deal, contestants choose from among 26 briefcases held by 26 models. Each of these briefcases contains a different amount of money ranging from $0.01 to $1,000,000. The contestant begins by choosing one briefcase, then starts selecting other cases to open, hoping to reveal small cash amounts because this will improve the odds of winning the $1 million. After a predetermined number of cases are opened, 'the Banker' tries to tempt the player to exchange her case for an amount of instant cash. The player must either stick with her original briefcase choice ('No Deal'), or make a 'Deal' with the Banker to accept his cash offer in exchange for whatever dollar amount is in the chosen case.The show is a terrific example of financial decision making under risk. Nobel prize recipient Daniel Kahneman and his colleague Amos Tversky developed the idea of prospect theory to explain how people decide between alternatives that involve risk, when the outcome is uncertain but the probabilities are known (or estimated). Their highly influential paper (Kahneman & Tversky, 1979) framed these ideas, which provided an alternative to the expected utility hypothesis:What does any of this have to do with dots??The University of Rochester issued an egregiously erroneous press release to accompany the publication of a new paper in Neuron (Beck et al., 2008):Our Unconscious Brain Makes the Best Decisions PossibleNew Research Shows the Human Brain Computes Extremely Well—Given What it KnowsResearchers at the University of Rochester have shown that the human brain—once thought to be a seriously flawed decision maker—is actually hard-wired to allow us to make the best decisions possible with the information we are given.Let's see, the study was done in monkeys (not humans), and the results said absolutely nothing about proving the brain is "hard-wired" to make the best decisions possible. The paper used computational methods to analyze the spike trains of neurons in the lateral intraparietal (LIP) area of monkeys who were trained to make motion discriminations. The original data were taken from the paper of Anne Churchland et al. (2008). One of the experimental tasks is illustrated below.Figure 1A (Beck et al., 2008). Binary decision making. The subject must decide whether the dots are moving to the right or to the left. Only a fraction of the dots are moving to the right or the left coherently (black arrows). The other dots move in random directions. The animal indicates its response by moving its eyes in the perceived direction (green arrow).Another variant of the task involved four choices instead of two (Churchland et al., 2008). In the Neuron paper, Beck et al. described a neural network model of decision making in these tasks. Although the motion direction task has been extensively studied in both animals and humans, the reported model is clearly based on recordings of LIP neurons in rhesus monkeys.Back to paragraph #2 of the press release:Neuroscientists Daniel Kahneman and Amos Tversky received a 2002 Nobel Prize for their 1979 research that argued humans rarely make rational decisions. Since then, this has become conventional wisdom among cognition researchers.Kahneman and Tversky are/were (respectively) psychologists, not neuroscientists, and Tversky did not receive the Nobel prize. Perceptual discrimination of motion direction is not the same thing as financial decision making under risk, with its cognitive and affective elements. Although the monkeys were rewarded for correct decisions, reward functions were not a part of the network model. The authors summarized the significance of their work as follows:First, we show that for Poisson-like distributions, optimal evidence accumulation can be performed through simple integration of neural activities, while optimal response selection can be implemented through attractor dynamics. Second, we show (again for Poisson-like distributions of neural activity) that neurons encode the posterior probability distribution over the variables of interest at all times. This latter contribution has far-reaching implications, since it suggests that neurons implicated in simple perceptual decisions represent quantities that are directly relevant to inference, confidence, and belief.However, they didn't directly extrapolate their results to behavioral economics, and they didn't cite Kahneman and Tversky. Neverthess, the press release by the Senior Science Press Officer continues:Contrary to Kahnneman and Tversky's research, Alex Pouget, associate professor of brain and cognitive sciences at the University of Rochester, has shown that people do indeed make optimal decisions—but only when their unconscious brain makes the choice.At the risk of sounding pedantic, people did not make the decisions (monkeys did), and there was nary a mention of conscious vs. unconscious processing in the paper."A lot of the early work in this field was on conscious decision making, but most of the decisions you make aren't based on conscious reasoning," says Pouget. "You don't consciously decide to stop at a red light or steer around an obstacle in the road. Once we started looking at the decisions our brains make without our knowledge, we found that they almost always reach the right decision, given the information they had to work with." Pouget says that Kahneman's approach was to tell a subject that there was a certain percent chance that one of two choices in a test was "right." This meant a person had to consciously compute the percentages to get a right answer—something few people could do accurately.. . ."We've been developing and strengthening this hypothesis for years—how the brain represents probability distributions," says Pouget. "We knew the results of this kind of test fit perfectly with our ideas, but we had to devise a way to see the neurons in action. We wanted to see if, in fact, humans are really good decision makers after all, just not quite so good at doing it consciously. Kahneman explicitly told his subjects what the chances were, but we let people's unconscious mind work it out. It's weird, but people rarely make optimal decisions when they are told the percentages up front."I don't know if there would be any differences in the results if the monkeys were told the percentages up front... but you can watch Professor Kahneman discuss Decision Making and Rationality in Deal or No Deal Decisions, now showing on Channel N.ReferencesJ BECK, W MA, R KIANI, T HANKS, A CHURCHLAND, J ROITMAN, M SHADLEN, P LATHAM, A POUGET (2008). Probabilistic Population Codes for Bayesian Decision Making Neuron, 60 (6), 1142-1152 DOI: 10.1016/j.neuron.2008.09.021Churchland AK, Kiani R, Shadlen MN. (2008). Decision-making with multiple alternatives. Nat Neurosci. 11:693-702.Kahneman D, Tversky A. (1979). Prospect theory: An analysis of decision under risk. Econometrica 47: 263-291.... Read more »

J BECK, W MA, R KIANI, T HANKS, A CHURCHLAND, J ROITMAN, M SHADLEN, P LATHAM, & A POUGET. (2008) Probabilistic Population Codes for Bayesian Decision Making. Neuron, 60(6), 1142-1152. DOI: 10.1016/j.neuron.2008.09.021

April 10, 2008
03:01 AM
803 views

Staplers, Snakes, and Sex

by The Neurocritic in The Neurocritic

Do sexy pictures make men more likely to buy expensive sports cars? Possibly, according to Science Daily:Irrelevant Image Of Attractive Woman Can Make A Man More Willing To Take Big Financial RisksScienceDaily (Apr. 5, 2008) — Attractive women plus cool cars equal brisk sales for auto dealers as men snap up those cars, prompted—or so advertising theory goes—by the association. But is the human male really so easily swayed? Can the irrelevant image of an alluring female posing by the merchandise actually encourage a heterosexual man to purchase it?Possibly, ... Read more »

B Knutson, G Wimmer, C Kuhnen, & P Winkielman. (2008) Nucleus accumbens activation mediates the influence of reward cues on financial risk taking. Neuroreport, 19(5), 509-513.

Biology

August 15, 2010
06:47 PM
802 views

Airplane Headache

by The Neurocritic in The Neurocritic

Cartoon Reenactment of JetBlue Flight Attendant’s Dramatic ExitNo, the term "airplane headache" does not refer to disgruntled JetBlue flight attendant Steven Slater (or to being a passenger on that flight). Instead, it refers to a recently characterized type of headache that occurs during take-off and landing (Atkonson & Lee, 2004). The pain appears to be unique to plane travel and not associated with other conditions. Neurological exam and brain imaging results in all published cases (n=14) have been normal.A new case study of a man with airplane headaches has been reported by Domitrz (2010). Clinical details are as follows:A 29-year-old healthy man, who works as a psychologist, reported that during his last airplane journey, he developed a very severe and sudden jabbing headache located in the left frontal region with radiation into the left eye. It started during take-off, diminished during the 2-h flight, a very mild pain was present during the flight and increased during plane’s descent and lasted until a few minutes after landing. Then, the pain completely and spontaneously subsided. The same situation took place 3 days later when the patient was returning. He remembers that he had similar, but milder headaches during previous flights. However, they occurred only during airplane flights and did not develop during jumbo jet flights. Similar headache did not appear in other altitude variation moments, e.g. in mountain trips.The pain was always located in the left frontal region with radiation into the left eye without any autonomic symptoms and neurological focal problems. He could not move until the headache disappeared. The patient has no medical history of sinus problems and using any medications. The family history has shown only tension type headache in patient’s 4 years older sister. General (including blood pressure and heart rate), neurological, otolaryngological and ophthalmological examinations were normal. Brain magnetic resonance imaging also with angiography excluded any structural lesions and arterial malformations. Domitrz (2010) further notes that most reported cases have been in young males, as is her patient. She is also puzzled by why he gets these headaches only on airplanes that are not jumbo jets -- perhaps it is connected with differences in air pressure, she speculates.What causes this specific type of headache? One view is that barotrauma is involved, with pressure changes affecting the trigeminovascular system (Berilgen & Müngen, 2006):We think that barotrauma caused by pressure changes in the cabin during take-off and landing could affect ethmoidal nerves (branching from the ophthalmic branch of the trigeminal nerve) that carry the senses of the mucosa on the inner surface of the paranasal sinuses, and/or nociceptors in ethmoidal arteries, thereby activating the trigeminovascular system and leading to headache.It's enough to make someone attempt an emergency exit!ReferencesAtkonson V, Lee L. (2004). An unusual case of an airplane headache. Headache 44:438–439Berilgen MS, Müngen B. (2006). Headache associated with airplane travel: report of six cases. Cephalalgia 26:707-11.Domitrz, I. (2010). Airplane headache: a further case report of a young man. The Journal of Headache and Pain DOI: 10.1007/s10194-010-0245-9

... Read more »

Domitrz, I. (2010) Airplane headache: a further case report of a young man. The Journal of Headache and Pain. DOI: 10.1007/s10194-010-0245-9

May 19, 2011
03:09 AM
801 views

Improving the Physical Health of People With Serious Mental Illness

by The Neurocritic in The Neurocritic

Today is the Mental Health Blog Party sponsored by the American Psychological Association as part of Mental Health Month. A widely neglected part of mental health treatment is encouraging and maintaining good physical health. This is extremely difficult when some of the major drugs prescribed for serious mental illnesses (such as schizophrenia and bipolar disorder) produce substantial weight gain. The "second generation" or atypical antipsychotics can cause obesity and hence diabetes, hypertension, cardiovascular problems, high cholesterol, and stroke.Yesterday the BBC posted this headline:Mentally ill have reduced life expectancy, study findsBy Dominic Hughes Health correspondent, BBC NewsPeople suffering from serious mental illnesses like schizophrenia or bipolar disorder can have a life expectancy 10 to 15 years lower than the UK average.Researchers tracked the lives of more than 30,000 patients through the use of electronic medical records.They found that many were dying early from heart attack, stroke and cancer rather than suicide or violence.Mental health groups say vulnerable people need to be offered better care to prevent premature deaths.. . . "We need to improve the general health of people suffering from mental disorders by making sure they have access to healthcare of the same standard, quality and range as other people, and by developing effective screening programmes."The BBC article referred to a paper that was published today in PLoS ONE (Chang et al., 2011). The authors reviewed the electronic database of a major mental health care provider (the South London and Maudsley NHS Foundation Trust). The results were alarming (but not new, unfortunately):A total of 31,719 eligible people, aged 15 years or older, with SMI [serious mental illness] were analyzed. Among them, 1,370 died during 2007–09. Compared to national figures, all disorders were associated with substantially lower life expectancy: 8.0 to 14.6 life years lost for men and 9.8 to 17.5 life years lost for women. Highest reductions were found for men with schizophrenia (14.6 years lost) and women with schizoaffective disorders (17.5 years lost). click on image for a larger viewFigure 1 (Chang et al., 2011). Annual mortality risk (%) by age groups and diagnoses of mental illness, compared to England and Wales population in 2008.The figure above illustrates the 2008 population of England and Wales in the red bars for five different age group: 15-29, 30-44, 45-59, 60-74, and 75+. Those with substance use disorders are shown in maroon, schizoaffective disorder in green, bipolar disorder in purple, schizophrenia in aqua, and depression/recurrent depression in light brown.Mortality risk is increased for all psychiatric diagnoses, and is especially evident in the middle three age groups. Life expectancies were estimated using these data, and the resultsconfirmed substantially shortened life expectancies at birth for all serious mental disorder groups investigated compared to national norms. Largest reductions were found for men with schizophrenia, women with schizoaffective disorders, and both men and women with substance use disorders.Why might this be? The authors do not speculate beyond stating that the "underlying causes may be multiple." Certainly, one can imagine that medication-induced weight gain [and increased levels of smoking] among the SMI contributes to lowered life expectancies.To counteract these dismal statistics, a regular part of mental health treatment should include programs that promote better physical health. Smoking cessation and nutritionists and structured exercise classes in addition to standard psychiatric care and substance abuse treatment.A six month intervention pilot study in Maryland enrolled 63 overweight participants at psychiatric rehabilitation day programs (Daumit et al., 2010):Results: ... In total, 52 (82%) completed the study; others were discharged from psychiatric centers before completion of the study. Average attendance across all weight management sessions was 70% (87% on days participants attended the center) and 59% for physical activity classes (74% on days participants attended the center). From a baseline mean of 210.9 lbs (s.d. 43.9), average weight loss for 52 participants was 4.5 lb (s.d. 12.8) (P<0.014). On average, participants lost 1.9% of body weight. Mean waist circumference change was 3.1 cm (s.d. 5.6). Participants on average increased the distance on the 6-minute walk test by 8%.Conclusion: This pilot study documents the feasibility and preliminary efficacy of a behavioral weight-loss intervention in adults with serious mental illness who were attendees at psychiatric rehabilitation centers...Although a 2% loss of body weight may not seem like much, it's better than a 10% weight gain over the same time period. The medical profession is obligated to provide the means for improved physical health in persons with serious mental illnesses. When physical health is potentially compromised by psychiatric treatments such as atypical antipsychotics, action to improve the situation is even more urgent.ReferencesChang, C., Hayes, R., Perera, G., Broadbent, M., Fernandes, A., Lee, W., Hotopf, M., & Stewart, R. (2011). Life Expectancy at Birth for People with Serious Mental Illness and Other Major Disorders from a Secondary M... Read more »

Chang, C., Hayes, R., Perera, G., Broadbent, M., Fernandes, A., Lee, W., Hotopf, M., & Stewart, R. (2011) Life Expectancy at Birth for People with Serious Mental Illness and Other Major Disorders from a Secondary Mental Health Care Case Register in London. PLoS ONE, 6(5). DOI: 10.1371/journal.pone.0019590

Daumit, G., Dalcin, A., Jerome, G., Young, D., Charleston, J., Crum, R., Anthony, C., Hayes, J., McCarron, P., Khaykin, E.... (2010) A behavioral weight-loss intervention for persons with serious mental illness in psychiatric rehabilitation centers. International Journal of Obesity. DOI: 10.1038/ijo.2010.224

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