All posts from Last Month
- April 19, 2013
- 01:50 AM
- 121 views
Do smart drugs ACTUALLY make you smarter?
by Shelly Fan in Neurorexia
T’is the season of finals again, and with it, a surging interest in prescription “smart drugs” (see Fig 1). High school and college students are increasingly turning to ADHD medicine (Ritalin, Adderall) in hopes of enhancing school and test performance. Intuitively this makes sense: drugs that increase energy, attention and concentration should inevitably lead to [...]... Read more »
Lakhan SE, & Kirchgessner A. (2012) Prescription stimulants in individuals with and without attention deficit hyperactivity disorder: misuse, cognitive impact, and adverse effects. Brain and behavior, 2(5), 661-77. PMID: 23139911
Smith ME, & Farah MJ. (2011) Are prescription stimulants "smart pills"? The epidemiology and cognitive neuroscience of prescription stimulant use by normal healthy individuals. Psychological bulletin, 137(5), 717-41. PMID: 21859174
- April 19, 2013
- 12:23 AM
- 87 views
Was the Push For an Assault Weapons Ban a Bad Idea? Digging into the “Door In the Face” Technique
by Eric Horowitz in peer-reviewed by my neurons
The Senate’s sad failure to pass any kind of gun control legislation has led to the rehashing of what can now be deemed failed political tactics. Much of the focus has been on the decision of gun control advocates to initially pursue an assault weapons ban: Congressional consideration was also delayed by gun control proponents’ [...]... Read more »
Cialdini, R., & et al, . (1975) Reciprocal concessions procedure for inducing compliance: The door-in-the-face technique. Journal of Personality and Social Psychology, 31(2), 206-215. DOI: 10.1037/h0076284
Feeley, T., Anker, A., & Aloe, A. (2012) The Door-in-the-Face Persuasive Message Strategy: A Meta-Analysis of the First 35 Years. Communication Monographs, 79(3), 316-343. DOI: 10.1080/03637751.2012.697631
- April 18, 2013
- 09:02 PM
- 108 views
Existential Dread of Absurd Social Psychology Studies
by The Neurocritic in The Neurocritic
Scene from Rabbits by David Lynch“In a nameless city, deluged by a continuous rain, three rabbits live with a fearful mystery.”The latest "elegant and breathtaking"1 paper in Psychological Science presents a rather muddled view of film aesthetics, continental philosophy, surrealism, mortality salience, and stigmatizing attitudes towards sex work (Randles et al., 2013). Oh, and how Tylenol® brand acetaminophen can ease the existential dread evoked by all of these modern horrors.The authors explained the purpose and implications of their study in the APS press release:According to lead researcher Daniel Randles and colleagues at the University of British Columbia in Canada, the new findings suggest that Tylenol may have more profound psychological effects than previously thought:“Pain extends beyond tissue damage and hurt feelings, and includes the distress and existential angst we feel when we’re uncertain or have just experienced something surreal. Regardless of the kind of pain, taking Tylenol seems to inhibit the brain signal that says something is wrong.”Randles and colleagues knew from previous research that when the richness, order, and meaning in life is threatened — with thoughts of death, for instance — people tend to reassert their basic values as a coping mechanism.The researchers also knew that both physical and social pain — like bumping your head or being ostracized from friends — can be alleviated with acetaminophen. Randles and colleagues speculated that the existentialist suffering we face with thoughts of death might involve similar brain processes. If so, they asked, would it be possible to reduce that suffering with a simple pain medicine?No!! I think this is a ridiculous assertion that gets away with using language (and dependent measures) that not only lack precision, but also lack an analogical relation to the real phenomenon under discussion. The leaps of logic were so egregious that I don't know where to begin......so let's start with the meaning-maintenance model (MMM) that motivated the work. MMM "posits that any violation of expectations leads to an affective experience that motivates compensatory affirmation" (Randles et al., 2013). Any violation?? So all sorts of psycholinguistics experiments that involve syntactic violations 2 will motivate compensatory affirmation? If that's the case, then David Lynch films will often "motivate compensatory affirmation."But does a David Lynch film “hurt” you?...Lynch’s films have the ability to “disturb, offend or mystify” (Rodley, 2005, p. 245). Insofar as it “hurts” to watch some of Lynch’s films, as it arguably hurts whenever one is assaulted by thoughts and experiences that are at odds with one’s expectations and values, the question arises as to how this uncomfortable feeling is represented in the brain. First, David Lynch is one of my favorite directors, and I have never felt "hurt" by watching one of his films. Second, Randles et al. never, at any point in their experiments, address how Lynch-viewing is represented in the brain.What did the authors actually do? In brief, they asked ~350 young Vancouverites to participate in one of two experiments. In the first study, 121 subjects wrote about death or about dental pain. In the second study, 228 subjects watched a 4 min clip from Rabbits or from The Simpsons. In each case, half of the participants received acetaminophen, half received placebo. Why? What motivated the choice of acetaminophen, as opposed to aspirin, ibuprofen, or naproxen? This was based on a study by Dewall et al. (2010), another problematic paper3 in Psych Sci. There was no mechanistic reason for the original choice.Here's the neuro-rationale for the current study (Randles et al., 2013):The present research is predicated on four key findings in the literature: (a) Both physical and social pain are associated with activation in the dACC [dorsal anterior cingulate cortex]4 (e.g., Eisenberger et al., 2003), (b) the dACC is activated in response to anomalies (e.g., Botvinick et al., 2004), (c) social rejection can produce the same compensatory affirmation as other meaning threats (e.g., Nash et al., 2011), and (d) acetaminophen has been shown to reduce physical and social pain, as well as activation in the dACC (DeWall et al., 2010). These findings led us to predict that acetaminophen may also inhibit compensatory affirmation following meaning threats.The acetaminophen group in Dewall et al. (dose of 2,000 mg a day for 3 weeks) did show less dACC activity in response to cyberball exclusion, but they did not report lower hurt feelings in that situation. The treatment administered by Randles et al. was quite different: a single acute dose of 1,000 mg Tylenol-brand acetaminophen (Rapid Release formula) or 1,000 mg sugar placebo, given 30 min before the critical manipulation.In Exp. 1, writing two paragraphs about what will happen to your body after death was designed to trigger mortality salience, or thoughts about the inevitability of death. This in turn would lead to compensatory affirmation of cultural views. How was this measured? By assessing the severity of punitive attitudes towards women who engage in sex work! This is the worst part of the study, in my opinion.Social judgment surveyFinally, participants read a hypothetical arrest report about a prostitute and were asked to set the amount of the bail (on a scale from $0 to $999). This measure has been used in a number of other meaning-threat studies (Proulx & Heine, 2008; Proulx et al., 2010; Randles et al., 2011; Rosenblatt, Greenberg, Solomon, Pyszczynski, & Lyon, 1989). Participants are expected to increase the bond amount after experiencing a threat, because trading sex for money is both at odds with commonly held cultural views of relationships and against the law. Increasing the bond assessment provides participants n opportunity to affirm their belief that prostitution is wrong. The study took place in Vancouver, Canada. What are the laws on prostitution?In Canada, the buying and selling of sexual services are leg... Read more »
Randles, D., Heine, S., & Santos, N. (2013) The Common Pain of Surrealism and Death: Acetaminophen Reduces Compensatory Affirmation Following Meaning Threats. Psychological Science. DOI: 10.1177/0956797612464786
- April 18, 2013
- 07:36 PM
- 99 views
Can we functionally cure HIV?
Last March, Dr. Deborah Persaud, from the John's Hopkins Children Center, presented a stunning finding at the conference CROI, receiving great resonance across several newscasts: Persaud reported the first case of infant functionally cured of HIV. You can watch Persaud's presentation by downloading the podcast here, it's the seventh talk of the session "Is there hope for HIV eradication?"Up until this finding, the only living person cured from HIV was the Berlin Patient, who was cured after receiving gene therapy for his underlying leukemia condition. Despite this one successful case, gene therapy is not a feasible way to cure HIV. What does it mean to be functionally cured?Once in the host, the HIV virus establishes reservoirs of latent virus: these are viral particles that stay dormant in cells and tissues and have the ability to quickly rebound in the event that therapy is discontinued. That's why it's so important for an HIV infected person to never discontinue the drug regimen, as the rebound virus may be drug resistant. HIV is so efficient at escaping the immune system and therapy that standard practice these days is a lifetime of not just one, but a cocktail of 3-4 antiretroviral drugs. To be functionally cured means that drugs are no longer needed to keep the viral load in check (close or below detection), something that until now had only been achieved by an extremely low number of HIV-positive individuals (less than 1% of infected adults), the so-called "elite controllers." In all other subjects, the reservoirs are never completely weakened and they enable the virus to bounce back once therapy is interrupted. So, what was different with this child?The mother went into labor without prenatal care. An HIV test was done during labor and normally, when the test is positive, antiretroviral drugs are administered. This is highly effective in preventing mother-to-infant infections as the only moment when the infant is exposed to the mother's blood is at birth. The antiretroviral drugs keep the viral load so low that the risk of infection becomes very small (around 2%). Unfortunately, in this particular case, the birth was so precipitous that there was no time to administer such drugs. The newborn baby was immediately tested for HIV. This is my understanding of what was unique about this case: normally a first test is done and, if positive, a second follow-up test is performed and prophylaxis is started once the infection is confirmed. In this case, though, two independent tests were done at the same time and, since both confirmed the HIV infection, prophylactic treatment was started very early, when the baby was 31 hours of age. Also, unique to this case was the fact that a regimen of three drugs, of which one at the therapeutic level instead of the standard prophylactic dosage, was administered during the first week of life. After that, the baby was switched to a standard treatment of antiretroviral drugs (again, my understanding from the CROI talk). Such regimen successfully brought the child's viral load down to undetectable, which is normal in these cases. Despite this, because of HIV's ability to establish reservoirs, antiretroviral therapy is never discontinued. Like I said before, it is a lifetime therapy. So called "drug holidays" result in more virulent and drug-resistant HIV quasispecies. However, this child was lost to follow-up at 18 months of age and was once again seen by the doctors at 25 months of age, when the caregiver reported discontinuing the therapy. Immediate testing was done to assess the child's viral loads. The child was tested not once, but many times. Genetic testing was also done to make sure it was the same child treated before. The doctors must have been in disbelief as for the first time they were seeing the incredible: after 5 months since discontinuing antiretroviral therapy, the viral load in this child was still undetectable. What are the consequences? As Dr. Persaud repeated many times during her talk, this is a single case and a proof of concept. We need more cases to be able to generalize (as statistics teach us). However, it points to something that indeed needs to be explored: how early in the infection can we (and should we) intervene? In a 2012 paper [1], Persaud and colleagues studied the dynamics of the latent HIV reservoirs in 17 infants on very early antiretroviral drug therapy (median start age 8 weeks) and found that the size of the reservoirs at age 2 was associated to how early undetectable viral loads were achieved during therapy. The earlier viral load was suppressed through therapy, the smaller the HIV reservoir at age 2. Is there a point, very early into the infection, when the virus is vulnerable and all reservoirs can be not just reduced in size, but actually completely eradicated through potent and prompt intervention? In rare cases, HIV-infected patients are able to spontaneously maintain their viral load at a very low level without the need of drugs, the so called "elite controllers." What if, when administered early enough, antiretroviral drugs could transfer this type of spontaneous protection to every HIV-infected person? Shortly after the CROI conference, a French study published in PLoS Pathogens [2] reported 14 cases of what they call "post-treatment controllers," in other words, people whose viral loads remained very low after interrupting treatment. With the exception of mother-to-infant transmissions at birth, it's extremely hard to catch this virus early because people often don't realize they've been infected: symptoms, if any, appear 3-4 weeks later and are often mistaken for a common cold. Twelve of the 14 cases reported in [2] had symptoms that prompted early intervention and start of therapy during the primary infection."Post-treatment controllers (PTCs) had a more severe primary infection with higher viral loads and were frequently symptomatic, which may have prompted the early treatment in some cases [. . .] Therefore, our results strongly suggest that the infection control in the PTCs was not achieved spontaneously and was favored by the early onset of therapy. Because the interruption of long-term antiretroviral therapy initiated early during primary infection is not recommended, only a very small proportion (~2%) of the patients in the French Hospital Database on HIV Infection experienced such an interruption, which may explain the rarity of PTCs worldwide [2]."[1] Persaud, D., Palumbo, P., Ziemniak, C., Hughes, M., Alvero, C., Luzuriaga, K., Yogev, R., Capparelli, E., & Chadwick, E. (2012). Dynamics of the resting CD4+ T-cell latent HIV reservoir in infants initiating HAART less than 6 months of age AIDS, 26 (12), 1483-1490 DOI: 10.1097/QAD.0b013e3283553638[2] Sáez-Cirión, A., Bacchus, C., Hocqueloux, L., Avettand-Fenoel, V., Girault, I., Lecuroux, C., Potard, V., Versmisse, P., Melard, A., Prazuck, T., Descours, B., G... Read more »
Persaud, D., Palumbo, P., Ziemniak, C., Hughes, M., Alvero, C., Luzuriaga, K., Yogev, R., Capparelli, E., & Chadwick, E. (2012) Dynamics of the resting CD4 T-cell latent HIV reservoir in infants initiating HAART less than 6 months of age. AIDS, 26(12), 1483-1490. DOI: 10.1097/QAD.0b013e3283553638
Sáez-Cirión, A., Bacchus, C., Hocqueloux, L., Avettand-Fenoel, V., Girault, I., Lecuroux, C., Potard, V., Versmisse, P., Melard, A., Prazuck, T.... (2013) Post-Treatment HIV-1 Controllers with a Long-Term Virological Remission after the Interruption of Early Initiated Antiretroviral Therapy ANRS VISCONTI Study. PLoS Pathogens, 9(3). DOI: 10.1371/journal.ppat.1003211
- April 18, 2013
- 04:04 PM
- 42 views
fMRI: More Voxels, More Problems?
by Neuroskeptic in Neuroskeptic_Discover
A new paper could prompt a rethink of a technique that’s become very hot in neuroscience lately: Confounds in multivariate pattern analysis The authors are Princetonians Michael T. Todd and colleagues, and the method in question is multivariate pattern analysis (MVPA). I’ve written about this before and there’s a blog dedicated to it. MVPA searches [...]... Read more »
Todd, M., Nystrom, L., & Cohen, J. (2013) Confounds in multivariate pattern analysis: Theory and rule representation case study. NeuroImage. DOI: 10.1016/j.neuroimage.2013.03.039
- April 18, 2013
- 02:46 PM
- 81 views
What causes fatigue? Why is it different in CrossFit?
by AB Kirk in Stff Competition
What causes fatigue? And why is it sometimes so hard to push through it? Few people enjoy the sensations of fatigue and pain that accompany intense exercise. While endurance athletesThe post What causes fatigue? Why is it different in CrossFit? appeared first on WODMasters Stiff Competition.... Read more »
Bassini A, Magalhães-Neto AM, Sweet E, Bottino A, Veiga C, Tozzi MB, Pickard MB, & Cameron LC. (2013) Caffeine Decreases Systemic Urea in Elite Soccer Players during Intermittent Exercise. Medicine and science in sports and exercise, 45(4), 683-690. PMID: 23135367
Wilkinson DJ, Smeeton NJ, & Watt PW. (2010) Ammonia metabolism, the brain and fatigue; revisiting the link. Progress in neurobiology, 91(3), 200-19. PMID: 20138956
Bassini-Cameron, A., Monteiro, A., Gomes, A., Werneck-de-Castro, J., & Cameron, L. (2008) Glutamine protects against increases in blood ammonia in football players in an exercise intensity-dependent way. British Journal of Sports Medicine, 42(4), 260-266. DOI: 10.1136/bjsm.2007.040378
- April 18, 2013
- 01:02 PM
- 51 views
The Daddy Chronicles: What Happened To My Testosterone?
by Psych Your Mind in Psych Your Mind
Zoë at two weeks
I'm not sure how many of you know this, but on March 19th of this year I became a new daddy. It's hard to describe the meaning of this event and its impact on my life, but here is a useful comparison that might put things into perspective: My dissertation was accepted for publication on the same day that my daughter was born and despite the near month passing, I still haven't filed the publication forms for the paper. Fatherhood changes the way I see the world in radical ways!
And yet, despite knowing the changes that fatherhood has brought on in my own life, I was still shocked to read about this little finding published in 2011 by Gettler and colleagues--fatherhood reduces testosterone... a lot.
Read More->... Read more »
Gettler LT, McDade TW, Feranil AB, & Kuzawa CW. (2011) Longitudinal evidence that fatherhood decreases testosterone in human males. Proceedings of the National Academy of Sciences of the United States of America, 108(39), 16194-9. PMID: 21911391
- April 18, 2013
- 12:39 PM
- 82 views
Too Much Energy Efficiency Can Be Hazardous to Your Health
by dailyfusion in The Daily Fusion
A study done at the University of Leeds suggests that the risk of hospital infection could dramatically increase when the windows in the ward are closed.... Read more »
Gilkeson, C., Camargo-Valero, M., Pickin, L., & Noakes, C. (2013) Measurement of Ventilation and Airborne Infection Risk in Large Naturally Ventilated Hospital Wards. Building and Environment. DOI: 10.1016/j.buildenv.2013.03.006
- April 18, 2013
- 11:10 AM
- 68 views
Another bizarre news about the deaths from Heart attacks
by Usman Paracha in SayPeople
Main Points:
Researchers found that the patients with heart problems, known as STEMI, already admitted in the hospital have 10 times more chances of dying from heart attack as compared to the patients, who get heart attack outside of the hospital and taken to the hospital quickly.
Journal:
Journal of the American Heart Association
Study Further:
World is full of strange events but humanity is even more strange. Researchers from University of North Carolina (UNC) School of Medicine, in this study, worked on a type of heart attack known as ST elevation myocardial infarction (STEMI) in the hospital inpatients (who are already admitted to the hospital).
"We found that the survival rate for outpatients brought to UNC Hospitals for STEMI treatment was slightly more than 96 percent," said George A. Stouffer, MD, distinguished professor in the UNC School of Medicine and senior author of the study. "But the survival rate for inpatients who suffered a STEMI was much lower, only 60 percent."
Although, this may in-part occurs due to the age difference of the people i.e. people already admitted to the hospital were older and sicker as compared to the people taken from the outside but according to Stouffer, there are still important differences.
Another possible explanation for this could be the effective training of the hospital team in the emergency departments, so that when a STEMI patient brought in from outside, the time of starting the treatment with angioplasty is fast i.e. about 45 minutes at UNC hospitals.
"In contrast, when patients who are in the hospital for a non-cardiac condition have a STEMI, the onset is not usually heralded by chest pain and thus health care providers may not suspect that a coronary artery has occluded. As a result, the time it takes for restoration of coronary blood flow for inpatients is much slower and more variable," Stouffer said.
“Inpatient STEMIs are a major health care problem, suggesting that efforts aimed at improving care of this patient population would have a large impact,” Researcher wrote, “We found that the incidence of inpatient STEMI in our institution was 3.4 per 10 000 hospital discharges and was associated with an in‐hospital mortality of 40%.”
Source:
ScienceDaily
Further Reading:
Dai X, Bumgarner J, Spangler A, Meredith D, Smith SC, & Stouffer GA (2013). Acute ST-Elevation Myocardial Infarction in Patients Hospitalized for Noncardiac Conditions. Journal of the American Heart Association, 2 (2) PMID: 23557748... Read more »
Dai X, Bumgarner J, Spangler A, Meredith D, Smith SC, & Stouffer GA. (2013) Acute ST-Elevation Myocardial Infarction in Patients Hospitalized for Noncardiac Conditions. Journal of the American Heart Association, 2(2). PMID: 23557748
- April 18, 2013
- 10:18 AM
- 66 views
Nonpurging Bulimia Nervosa: Where Does It Fit?
by Tetyana Pekar in Science of Eating Disorders
When most people think of bulimia nervosa, they think of binge eating and self-induced vomiting. While that is not incorrect, it is not the full picture either. In the current edition of the Diagnostic and Statistical Manual (DSM-IV), there are two subtypes of bulimia nervosa: purging (BN-P) and nonpurging (BN-NP). The difference lies in the types of compensation methods: patients with BN-P engage in self-induced vomiting, or the misuse of laxatives, diuretics, or enemas whereas patients with BN-NP use fasting or excessive exercise to compensate for binge eating.
How common in BN-NP? It is very hard to say. A small population-based study in Finland (less than 3,000 participants) found that 1.7% of the sample that bulimia nervosa, 24% had BN-NP (or 0.4% of the entire sample) (Keski-Rahkonen et al., 2009). (I couldn’t find much else on prevalence of BN-NP.)
Unfortunately, however, there’s been very little research on BN-NP.
So little, in fact, that many have wondered if it make sense to subtype bulimia nervosa patients into purging and nonpurging groups? And are there differences between patients with BN-NP and …
You May Also Like:
EDNOS, Bulimia Nervosa: As Deadly as Anorexia in Outpatients
Living in a Large City: A Risk Factor for Bulimia Nervosa?
Medical Complications of Purging in Bulimia Nervosa
... Read more »
van Hoeken, D., Veling, W., Sinke, S., Mitchell, J., & Hoek, H. (2009) The validity and utility of subtyping bulimia nervosa. International Journal of Eating Disorders, 42(7), 595-602. DOI: 10.1002/eat.20724
- April 18, 2013
- 10:15 AM
- 64 views
U.S. hospitals found more profit in complications in surgery
by Usman Paracha in SayPeople
Main Point:
Researchers found that the U.S. hospitals get more profit when the surgery goes wrong as compared to the condition when all the tasks go well and patients go home without any complications.
Journal:
The Journal of the American Medical Association (JAMA)
Study Further:
Quite disturbing report but one of the points to consider in healthcare system is that the finances spent on that industry have to be properly planned.
Do you know nearly $400 billion is spent on the surgical procedures annually, in U.S. only?
For the past few years, effective methods and ways to cut the complications have been introduced in so many researches but hospitals were found slow in getting and implementing those ways. Now researchers have found that finances could be one of the reasons.
“We found clear evidence that reducing harm and improving quality is perversely penalized in our current health care system,” Sunil Eappen, study author and chief medical officer of Massachusetts Eye and Ear Infirmary, said in a statement.
Researchers found that privately insured surgical patients with complications provided hospitals nearly 330% more profit as compared to the patients with no complications. Medicare patients with some complications provided more than 190% margin.
“It’s been known that hospitals are not rewarded for quality. But it hadn’t been recognized exactly how much more money they make when harm is done,” said senior author Atul Gawande, director of Ariadne Labs, professor in the Department of Health Policy and Management at HSPH and a surgeon at BWH.
It means reducing complications decreases financial achievements of the hospitals.
“This is clear indication that health care payment reform is necessary,” said Gawande. “Hospitals should gain, not lose, financially from reducing harm.”
I think we have to study the same thing in other developed countries.
Source:
Harvard University, The Raw Story
Further Reading:
Eappen, S. (2013). Relationship Between Occurrence of Surgical Complications and Hospital Finances JAMA, 309 (15) DOI: 10.1001/jama.2013.2773... Read more »
Eappen, S. (2013) Relationship Between Occurrence of Surgical Complications and Hospital Finances. JAMA, 309(15), 1599. DOI: 10.1001/jama.2013.2773
- April 18, 2013
- 09:28 AM
- 91 views
Researchers identify compound that could prevent acute myeloid leukemia relapses
by beredim in Stem Cells Freak
In a new study on mice, researchers from the RIKEN Institute, Japan have discovered a compound that could be used to prevent cancer relapse in acute myeloid leukaemia (AML) patients, especially the ones carrying the FLT3-ITD mutation.Read More... Read more »
Saito, Y., Yuki, H., Kuratani, M., Hashizume, Y., Takagi, S., Honma, T., Tanaka, A., Shirouzu, M., Mikuni, J., Handa, N.... (2013) A Pyrrolo-Pyrimidine Derivative Targets Human Primary AML Stem Cells in Vivo. Science Translational Medicine, 5(181), 181-181. DOI: 10.1126/scitranslmed.3004387
- April 18, 2013
- 09:06 AM
- 45 views
Tracking exosomes in vivo
by Kasra Hassani in The Parasite Diary
Posted by: Kasra Application of exosomes for therapeutic, especially as drug delivery agents has been always an interest. However, there is limited knowledge on how these vesicles interact with the variety of the cells inside the body and how does the body react to their presence. Takahashi et al. have used exosomes released by a [...]... Read more »
Takahashi Y, Nishikawa M, Shinotsuka H, Matsui Y, Ohara S, Imai T, & Takakura Y. (2013) Visualization and in vivo tracking of the exosomes of murine melanoma B16-BL6 cells in mice after intravenous injection. Journal of biotechnology. PMID: 23562828
- April 18, 2013
- 08:17 AM
- 38 views
Predictions About Workplace Sexual Harassment: Experiencers, Observers, Predictors, and the Psychological Immune System
by Dan DeFoe in Psycholawlogy
Judges, jurors, lawyers, and EEO investigators evaluate possible instances of sexual harassment. Their judgments stem from assumptions about whether the complainant experienced unwelcome, severe, and pervasive conduct in a hostile work environment. Psycho-legal researchers identify these persons as “predictors”. Predictors do not directly experience or observe the workplace misconduct. Instead, they gauge the impact [...]The post Predictions About Workplace Sexual Harassment: Experiencers, Observers, Predictors, and the Psychological Immune System appeared first on Psycholawlogy.... Read more »
Wiener, R., Gervais, S., Allen, J., & Marquez, A. (2012) Eye of the Beholder: Effects of Perspective and Sexual Objectification on Harassment Judgments. Psychology, Public Policy, and Law. DOI: 10.1037/a0028497
- April 18, 2013
- 07:49 AM
- 13 views
Holey Biofilm!
by Moselio Schaechter in Small Things Considered
As a child, I was always fascinated by the holes (or eyes) in Swiss cheese, always inspecting the tunneling system before getting a good bite. Although the holes are the result of microbial activity (the accumulation of CO2 released by fermentative bacteria), I bring up the Swiss cheese analogy for very different reasons. Try to picture a similar landscape of tunnels and holes in a bacterial biofilm. And that’s what today’s story is about … a ‘holey’ biofilm.
In a recent study published in PNAS, Houry and collaborators used time-lapse microscopy to monitor the biofilms formed by the bacterium Bacillus thuringiensis and noted that a small subset (0.1 to 1%) of all the cells in the biofilm were motile. The rest of the cells were sessile and immobile except for some minor oscillatory motions hampered by the surrounding biofilm matrix. The swimmers infiltrated the biofilms in all directions, creating a landscape of tunnels and holes like in Swiss cheese. By tagging planktonic cells (that is, cells growing free in the surrounding liquid) with the green fluorescent protein (GFP), the authors showed that the biofilm swimmers were in fact planktonic cells. The swimmers infiltrated the biofilms independently of the flow dynamics of the surrounding fluid and their tunneling activity was exclusively dependent on the rotational activity of their flagella. Despite the biofilm barrier, the swimmers had average velocities as high as 7.3 μm/s in young (24 h old) biofilms. For a movie showing these rapid motions, click here. The swimming velocities decreased progressively as the biofilms aged, with the lowest velocities (4.2 μm/s) being measured in the oldest (72h old) biofilms. This is because the biofilm matrix also becomes more dense and rigid over time (and, therefore, more difficult to permeate). Still, these speeds are remarkable for cells that are swimming through a biofilm matrix!... Read more »
Houry A, Gohar M, Deschamps J, Tischenko E, Aymerich S, Gruss A, & Briandet R. (2012) Bacterial swimmers that infiltrate and take over the biofilm matrix. Proceedings of the National Academy of Sciences of the United States of America, 109(32), 13088-93. PMID: 22773813
- April 18, 2013
- 07:13 AM
- 73 views
If You Could, Would You Eat Wood?
by Andrew Porterfield in United Academics
It doesn’t sound very appetizing; eating a tree branch or a wooden plank. But an engineering researcher at the Virginia Polytechnical Institute (Virginia Tech) in Blacksburg has found a way to convert the cellulose that makes up wood into starch.... Read more »
You C, Chen H, Myung S, Sathitsuksanoh N, Ma H, Zhang XZ, Li J, & Zhang YH. (2013) Enzymatic transformation of nonfood biomass to starch. Proceedings of the National Academy of Sciences of the United States of America. PMID: 23589840
- April 18, 2013
- 04:36 AM
- 82 views
Kidneys grown in the lab work in animals
by Isabel Torres in Science in the clouds
Researchers from the Massachusetts General Hospital in the US have grown rat kidneys in the laboratory that produced urine when transplanted into living animals. This is an important step towards the production of customised organs for transplantation into people with kidney failure, which could replace donor organ transplants. Patients with kidney failure can be treated with dialysis, but can only be cured with a kidney transplant. About 15,000 people are waiting for a donor kidney in the Eurotransplant region, but only 7,000 kidney transplants take place each year. Patients may wait up to five years for a donor kidney and many lose their lives during that time. A few research groups have attempted to make artificial kidneys, and some are trying to genetically modify pigs so their kidneys can be used in human transplants, but Harald Ott and his team take a different approach: they hope to grow kidneys in the laboratory using the patient’s own cells. This would put an end to donor organ shortage and immune rejection problems. “If this works, there wouldn’t be any need for immunosuppression or dialysis anymore, it would ... Read more »
Song Jeremy J, Guyette Jacques P, Gilpin Sarah E, Gonzalez Gabriel, Vacanti Joseph P, & Ott Harald C. (2013) Regeneration and experimental orthotopic transplantation of a bioengineered kidney. Nature Medicine. DOI: 10.1038/nm.3154
- April 18, 2013
- 04:16 AM
- 88 views
Exploiting children's social instincts to boost their learning
by Christian Jarrett in BPS Research Digest
Young children's instinct for group membership can be exploited to boost their learning performance. That's according to a new study that recalls classic social psychology research conducted in the 1970s. Back then Henri Tajfel showed a darker side to this group mentality. In his "minimal group" studies, schoolboys were divided into two groups based merely on their preference for one of two artists. The arbitrary groups thus formed, the boys showed immediate bias against peers not in their group.
In the new research, Allison Master and Gregory Walton allocated 55 children (average age 4 years; 32 boys) to one of three conditions before testing them on a challenging jigsaw puzzle. In one condition, the children were told that they were members of "the Blue Group" that did puzzles. Although they were alone, the children donned a blue t-shirt, sat on a blue chair, and the puzzle box had a blue sticker on it. They were further told that children in the "the Green group" do other things.
In the first of two control conditions, the children were told that they were "child number 3" and that "child number 3 does puzzles". They too had a t-shirt and other paraphernalia that signalled their new individual identity. In the second control condition, the children simply worked at the puzzle with no mention of groups or identities.
Even though they worked alone and there was no history to their group membership, the children in the Blue Group condition were fired up by their belonging to the group that does puzzles - they persisted 29 per cent longer on the puzzle than children in the "child number 3" condition and 35 per cent longer than children not allocated to a group or individual identity.
Master and Walton believe the children in the Blue Group condition readily internalised the purpose of the group - to do puzzles - in a way that didn't happen for kids in the the individual puzzle identity condition, or the no-intervention control condition.
To test this, a second study with 39 more children (average age 4 years; 18 boys) was similar to the first, but this time some of the children were allocated to a Blue Group that does puzzles, while others were allocated to a Blue Group without any mention of the group existing to do puzzles. Children in the Blue Group "that does puzzles" persisted for 39 per cent longer than the children in the purposeless Blue Group, thus reinforcing the idea that the benefit comes from readily internalising the group's stated raison d'être.
A third and final study followed a similar procedure but a word learning task was substituted for the puzzle task (it involved learning the names for four alien objects). The children led to believe they belonged to a group that "looks at alien toys and learns their names" later outperformed by 38 per cent other children who'd been told they were the child who "looks at alien toys and learns their names".
"These findings underscore the importance of group identity for young children's motivation and learning," the researchers said. "They suggest that children readily develop socially shared motivations with in-groups and that this shared motivation can lead children to put forth sustained effort on challenging academic tasks and to learn more from such tasks even in the absence of other children or members of their group."
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Master, A., and Walton, G. (2013). Minimal Groups Increase Young Children's Motivation and Learning on Group-Relevant Tasks. Child Development, 84 (2), 737-751 DOI: 10.1111/j.1467-8624.2012.01867.x
Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.
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Master, A., & Walton, G. (2013) Minimal Groups Increase Young Children's Motivation and Learning on Group-Relevant Tasks. Child Development, 84(2), 737-751. DOI: 10.1111/j.1467-8624.2012.01867.x
- April 18, 2013
- 02:00 AM
- 14 views
Continuing our exploration of group selection
by Eric Bolo in Evolutionary Games Group
This Tuesday, I gave the second of two presentations for the EGT Reading group, both focused on the theory of group selection. Though I am currently working outside of academia, it has been a pleasure to pursue my interests in ecology, and our group discussions have proven to be both enjoyable and challenging. The first [...]... Read more »
Marshall James A.R. (2011) Group selection and kin selection: formally equivalent approaches. Trends in Ecology , 26(7), 325-332. DOI: 10.1016/j.tree.2011.04.008
- April 17, 2013
- 10:50 PM
- 82 views
How stores trick our senses to make us buy more (Part 3 of 5: Touch)
by Jordan Gaines in Gaines, on Brains
Sure, a company can do its job to create an attractive, pleasurable product for us consumers. But—you guessed it—the store does its own part in tricking us, ensuring that the phrase "you touch it, you buy it" often holds true.... Read more »
James R. Wolf, Hal R. Arkes, & Waleed A. Muhanna. (2008) The power of touch: An examination of the effect of duration of physical contact on the valuation of objects. Judgment and Decision Making, 3(6), 476-482. info:/
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