Monk-Turner and Light (2010) hypothesise that men who are penetrated during the act of being sexually assaulted will be more likely to seek out professional help. Truth, alas, is even stranger than fiction...... Read more »
Monk-Turner E, & Light D. (2010) Male sexual assault and rape: who seeks counseling?. Sexual abuse : a journal of research and treatment, 22(3), 255-65. PMID: 20713746
Nearly everyone has heard of developmental dyslexia – a learning disorder characterized by poor reading skills despite otherwise sufficient schooling – but have you heard of developmental dyscalculia? Many people have not. Here is part 3 in a week-long series on this lesser-known learning disorder. (See parts one, and two, and a companion post at [...]... Read more »
Siegler, R. (1994) Cognitive Variability: A Key to Understanding Cognitive Development. Current Directions in Psychological Science, 3(1), 1-5. DOI: 10.1111/1467-8721.ep10769817
Geary, D. (1993) Mathematical disabilities: Cognitive, neuropsychological, and genetic components. Psychological Bulletin, 114(2), 345-362. DOI: 10.1037/0033-2909.114.2.345
Rosenberg PB. (1989) Perceptual-motor and attentional correlates of developmental dyscalculia. Annals of neurology, 26(2), 216-20. PMID: 2774508
Over at Discover magazine’s terrific Intersection blog, Sheril Kirshenbaum asks readers: “How might we shift public attitudes to be less wasteful and save energy on a massive scale?”
A major finding from social science research is that individual behavior choices are often shaped by perceptions of what other people are doing, especially our peers and other trusted individuals. A key agent in this process are what researchers call opinion-leaders, special individuals across communities and social groups that can serve as vital go-betweens and information brokers, passing on messages about energy conservation that speak directly to their otherwise inattentive peers, co-workers, and friends. In this “two step-flow of information,” opinion-leaders do not necessarily hold formal positions of power or prestige in communities, but rather serve as the connective communication tissue that alerted their peers to what mattered among political events, social issues, and consumer choices.
In a paper published last year (PDF) with my former student John Kotcher (now on the staff at the National Academies), we reviewed the several decades of research in the area, describing in specific ways how opinion-leaders can be used in both climate change and energy conservation campaigns.
Here’s part of what we wrote relevant to opinion-leader campaigns targeting consumer decisions, highlighting past research from the field of consumer behavior on the role of “market mavens” as opinion-leaders:
….previous research has identified “market mavens” as holding expertise and influence in broader marketplace-related information rather than just a type or class of consumer good. Market mavens are enthusiastic advice givers, with studies showing that mavens do not have to be early users or purchasers of a product to pass-on information. In lieu of personal product use, a market maven’s expertise derives from closer attention to magazines and consumer-focused Web sites. They also exhibit greater participation in activities such as using coupons, recreational shopping, reading advertisements, responding to direct mail, and providing retailers with personal information (Feick and Price, 1987; Walsh, Gwinner, & Swanson, 2004). In surveys, market mavens are identified using a six item scale first developed by Feick and Price (1987) [We include these measures in the appendix to the paper].
Market mavens can be valuable targets in …. campaigns promoting new energy-efficient products or consumer technology. Applied to these campaigns, Clark and Goldsmith (2005) recommend appealing to several identified personality attributes of market mavens including status and perceived uniqueness. Yet they also warn that market mavens do not want to purchase products that place them “too far outside” of perceived norms. The implication is that campaign messages and advertising should emphasize the “different but still socially acceptable” nature of a product, focusing on its newness and status-enhancing attributes.
An example relevant to [energy conservation] is the marketing success of Toyota’s Prius. In focus groups, prospective hybrid buyers say they believe that driving a distinctively-shaped Prius sends a conspicuous signal about values, a message that respondents expect to generate acclaim from peers. As auto manufacturers continue to introduce hybrid versions of their traditional models, they are now careful to let “buyers broadcast their earth-friendliness” by way of three-inch hybrid labels, and/or unique grille, wheels, or tail lights (Brand Neutral, 2006; Kerwin, 2003; Schneider, 2004).
In general, mavens talk significantly more about campaigns and sales at stores, and pay closer attention to advertising and special offers (Higie, Feick, & Price, 1987). Research also shows that market mavens are motivated psychologically by a sense of duty to pass on product information; by a sense of pleasure they derive from doing so; and by a desire to appear as a “competent helper” to friends and peers…
…this research suggests that advertising to mavens should emphasize appeals such as “Now that you know how [insert energy saving product] work, you have a duty to tell others.” Additionally, stores should make it easy for mavens to enjoy spreading the word about sustainable products, adding social media features to a campaign and creating rewards such as “bonus points” when mavens get others to purchase a product (Walsh, Gwinner, & Swanson, 2004). Overall, market-mavens hold important implications for big-box store chains such as Wal-Mart that have set “green” campaign goals that include selling fluorescent light bulbs and other energy-saving products. In reaching mass consumers, market-mavens are likely to be the central go-betweens for these stores.
What do readers think? Does the influence of opinion-leaders speak to your own personal experience?
I will have more on research related to opinion-leaders and energy behavior in a second post appearing later today.
Nisbet, M., & Kotcher, J. (2009). A Two-Step Flow of Influence?: Opinion-Leader Campaigns on Climate Change Science Communication, 30 (3), 328-354 DOI: 10.1177/1075547008328797... Read more »
Nisbet, M., & Kotcher, J. (2009) A Two-Step Flow of Influence?: Opinion-Leader Campaigns on Climate Change. Science Communication, 30(3), 328-354. DOI: 10.1177/1075547008328797
Put aside the dramatic Hollywood portrayals. Suited, married, high achieving, some of them walk among us. No, not vampires or super-heroes but 'successful psychopaths'. Like their criminally violent cousins - the standard psychopaths - these people are ruthless, callous, fearless and arrogant. But thanks to their superior self-control and conscientiousness, rather than landing in prison, they end up as company chief executives, university chancellors and Queen's Council barristers. Well, that's the idea anyway. But it's an idea that's proven difficult for psychologists to investigate. After all, if you advertise for volunteers for a study of successful people who are psychopathic, you're not likely to get many responses.
Stephanie Mullins-Sweatt and her collaborators tried a different tack. They surveyed hundreds of members of the American Psychological Association's Division 41 (psychology and law), criminal attorneys and professors of clinical psychology about whether they'd ever known personally an individual who was successful in their endeavours and who also matched Hare's definition of a psychopath: 'social predators who charm, manipulate and ruthlessly plow their way through life ... completely lacking in conscience and feeling for others, they selfishly take what they want and do as they please, violating social norms and expectations without the slightest sense of guilt or regret.'
Of the 118 APA members, 31 attorneys and 58 psychology professors who replied, 81, 25 and 41, respectively, said they'd previously known a successful psycho. The examples given were predominantly male and included current or former students, colleagues, clients, and friends (sample descriptions here). The survey respondents were asked to rate the personality of the successful psychopath they'd known and to complete a psychopathy measure of that person. These ratings were then compared with the typical profile for a standard (unsuccessful) psychopath.
The key difference between successful and standard psychopaths seemed to be in conscientiousness. Providing some rare, concrete support for the 'successful psychopath' concept, the individuals described by the survey respondents were the same as prototypical psychopaths in all regards except they lacked the irresponsibility, impulsivity and negligence and instead scored highly on competence, order, achievement striving and self-discipline.
'The current study used informant descriptions to provide information about successful psychopaths,' the researchers concluded. 'Such persons have been described in papers and texts on psychopathy but only anecdotally. This was the first study to conduct a systematic, quantitative analysis of such persons.'
Mullins-Sweatt, S., Glover, N., Derefinko, K., Miller, J., & Widiger, T. (2010). The search for the successful psychopath. Journal of Research in Personality, 44 (4), 554-558 DOI: 10.1016/j.jrp.2010.05.010
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Toronto team Rizo et al offer a novel approach to psychopharmacology: trawling the internet for people's opinions. It's a rapid, web-based method for obtaining patient views on effects and side-effects of antidepressants.They designed a script to Google the names of several antidepressants in the context of someone who's taking them, and checks to see if they describe any side-effects.A large number of URLs were rapidly screened through Google Search™, using one server situated in Ohio, USA. The search strategy used language strings to denote active antidepressant drug usage, such as “I'm on [name of antidepressant]…” or “Ihave been on [antidepressant] for ….”, or “I've started [antidepressant]…”, or “the [antidepressant] is giving me or causing me…”They then used a thing called OpenCalais™ to read the search hits and decide whether they were mentioning particular diseases or symptoms. OpenCalais is a natural language processor which is meant to be able to automatically extract the meaning from text. However, to make sure it wasn't doing anything silly (natural language processing is quite tricky), they manually checked the results.What happened? They found about 5,000 hits in total from people taking antidepressants, ranging from 210 for mirtazapine (Remeron) up to 835 for duloxetine (Cymbalta). That doesn't seem like all that many considering they searched on the entire internet, although they only searched English language websites.Anyway, drowsiness, sleepiness or tiredness was mentioned in from 6.4% (duloxetine) down to 2.9% (fluoxetine) of the hits. Insomnia was noted in 4% (desvenlafaxine) down to 2.2% fluoxetine. And so on.These results are a lot lower than anything previously reported from clinical trials, where the prevalence of drowsiness, for example, is often around 25% (vs. 10% on placebo); with some drugs, it's higher. So there's a big discrepancy, and it's hard to interpret these results. Maybe lots of people are having side effects and just not bothering to write about them. Or they're too embarrassed. Etc.Still, it's a very clever idea it would probably be better used trying to discover which drugs work best. Neuroskeptic readers will know that clinical trials of antidepressants are flawed in several ways. I'd say they're actually better at telling us about side effects (which are probably roughly the same in clinical trials and in real life) than they are at telling us about efficacy (where this assumption doesn't hold)...Links: There are many websites where people describe their experiences of medical treatments ranging from the fancy to the crude (but much more informative)...Rizo C, Deshpande A, Ing A, & Seeman N (2010). A rapid, Web-based method for obtaining patient views on effects and side-effects of antidepressants. Journal of affective disorders PMID: 20705344... Read more »
Rizo C, Deshpande A, Ing A, & Seeman N. (2010) A rapid, Web-based method for obtaining patient views on effects and side-effects of antidepressants. Journal of affective disorders. PMID: 20705344
If there is one finding that has remained pretty solid over the past 10 – 15 years, it’s the one that says being active is a good thing for managing chronic pain. I’m not sure how many papers I’ve read where ‘exercise’ and some form of cognitive behavioural approach have been found to produce improvements … Read more... Read more »
Pengel LH, Refshauge KM, Maher CG, Nicholas MK, Herbert RD, & McNair P. (2007) Physiotherapist-directed exercise, advice, or both for subacute low back pain: a randomized trial. Annals of internal medicine, 146(11), 787-96. PMID: 17548410
When we think of ourselves as being morally good or morally bad, what goes on in our brains? What moral memories does our mind gather to affirm that we are one or the other, and how are these memories influenced by cognitive biases?In some ways, we are already aware of some cognitive biases in the way we remember events. For example, we know of an "emotional bias" where emotional memories are remembered more vividly, are typically easier to retrieve and seem more familiar, even when the actual memories are not typically accurate. There also appears to be a"positivity bias" in that positive memories tend to be more vivid then negative ones and are less easily forgotten.Not much research has been done on moral memories and given that moral memories are often emotional ones (cheating on a partner for instance, or helping someone and receiving their gratitude in turn), similar cognitive biases might exist. In this study, the authors hypothesize that we would remember ourselves doing good deeds more recently, a sort of "temporal bias"The authors collected 700 autobiographical moral memories and characterized them on 3 categories of good versus bad. They also measured how long ago these events took place and collected data on possible contributing factors like gender, IQ, personality, etc. They then compared the mean age of the morally good memories to the morally bad memories and found that the morally good memories were always more recent.What could drive these findings? The authors list 3 distinct but fascinating possibilities.1) People actively reconstruct their memories to render their most recent acts, the acts to which one is most accountable, in a more positive light and relegate bad deeds to the distant past where one can come up with a host of reasons like "I was young" or "I didn't know better". This would be a real "temporal bias"2) Perhaps bad decisions are more emotionally arousing and hence are remembered better (refer to "emotional bias" above) and their memories, older. 3) There is some real difference in the way people act when they are younger and when they older, so they remember their older self as being more morally good while their younger self as being morally bad. This would be a non-psychological explanation for the phenomena examined above.While I think the study does indeed have several flaws that makes it hard to disentangle the possibilities, the idea it raises is quite exceptional. The way I interpret it is that, for the most part, we always strive to be better people, but we can never forget the wrongs that we have done. The solution that the brain seems to have evolved, if the authors are correct, is to relegate the ugly deeds to the past, and push the good to the present.Escobedo, J., & Adolphs, R. (2010). Becoming a better person: Temporal remoteness biases autobiographical memories for moral events. Emotion, 10 (4), 511-518 DOI: 10.1037/a0018723... Read more »
Escobedo, J., & Adolphs, R. (2010) Becoming a better person: Temporal remoteness biases autobiographical memories for moral events. Emotion, 10(4), 511-518. DOI: 10.1037/a0018723
Since becoming a parent, sleep has become a major issue in my life. Probably like many of you other parents out there, I was somewhat unprepared for months of interrupted sleep and how this would affect my overall well-being. Once my son was born, I began reading everything I could get my hands on about infant/childhood sleep in an effort to understand how to get my son to sleep better. This was not only a selfish endeavor, of course, as I knew he needed good sleep and it obviously made him feel better and be more engaging in learning and exploring. I was somewhat disappointed when I found that child development researchers seem to have overlooked the issue of sleep. I found many books/articles written my pediatricians that were helpful but I still felt there was a gap in the child development research concerning infant/toddler sleep, it's role in children's behavior, and the role of parents' behavior in helping children learn to sleep. Then, just last week I came across this great study conducted by child development researchers (yeah!) on the topic of sleep and parental responsiveness. I was excited to see this study and the fact that it was conducted at Pennsylvania State University, one of the top programs in Human Development and Family Studies, gave me hope that it would be a well-thought out study. This particular study examined parents' emotional responsiveness to infants/toddlers at bedtime and its association to how easily the child went to sleep and how well the child stayed asleep. Like me, many parents had always heard that a bedtime routine is key in helping an infant or toddler go to sleep easily and sleep peacefully. This study somewhat debunks this long-held thought. The researchers studied infants and young children (2 years and under) and their parents using direct observation via video cameras in their bedrooms. The results showed that parents' emotional responsiveness to children's moods and needs prior to bedtime were a better predictor of children's sleep than any sort of bedtime routine (i.e., reading books, quiet activities, etc.). So what does emotional responsiveness really mean? Well, it's probably many of the things parents commonly do with their child--speaking softly if the child seems upset, changing activities if the child seems uninterested with the current one. The researchers point out that being emotionally available to the child at bedtime helps them feel safe and this, in turn, makes it easier for them to go to sleep without a struggle. Personally, I don't think this means that you should throw out your bedtime routine, but it did make me think about the importance of flexibility. I think bedtime routines can be useful and also make children feel safe, however, children are different from day to day. Some nights reading a book and rocking in a chair may work great, but other nights a child may not be into reading a book. The key, it seems from this research, is to be attentive to the child's emotional needs at that particular moment. If the child doesn't seem interested in a book, the best option may be to move on to something else and not worry too much about the routine. This research seems to indicate that if you get to caught up in keeping the routine exactly the same (even if the child is resistant) it may end up making it more difficult for them to fall asleep. Hopefully more great research on sleep is coming down from the ivory tower soon!Teti, D., Kim, B., Mayer, G., & Countermine, M. (2010). Maternal emotional availability at bedtime predicts infant sleep quality. Journal of Family Psychology, 24 (3), 307-315 DOI: 10.1037/a0019306... Read more »
Teti, D., Kim, B., Mayer, G., & Countermine, M. (2010) Maternal emotional availability at bedtime predicts infant sleep quality. Journal of Family Psychology, 24(3), 307-315. DOI: 10.1037/a0019306
This post considering the evolutionary origins of numerical cognition, specifically in terms of the approximation of large numbers, is meant as a companion to this week's series on the developmental origins of numerical cognition and developmental dyscalculia, at Child's Play.
What are the origins of number representation in the mind? Are there any innate building blocks that contribute to our understanding of mathematics and number, or must everything be learned?
Number is an important domain of human knowledge. Many decisions in life are based on quantitative evidence, sometimes with life or death consequences.
Figure 1: Fight or flight?
By now you probably have come to expect that I'll be arguing that there are several innate "building blocks" of cognition that give rise to more complex mathematics. To start with, what are some of the arguments proposed by the empiricists?
(1) Number knowledge is entirely conceptual - it requires seeing objects as belonging to sets;
(2) Number knowledge is abstract. You need to understand the similarity between 3 people, 3 objects, 3 sounds, 3 smells, 3 dollars, 3 seconds, 3 hours, and 3 years;
(3) It doesn't appear to be cross-culturally universal. Some cultures have more advanced mathematics than others; and
(4) babies and monkeys can't do long division.
Surely, humans have something unique that allows us to do things like multivariate regression and construct geometric proofs, however, but let's start at the beginning. I will hopefully convince you that there is an evolutionarily-ancient non-verbal representational system that computes the number of individuals in a set. That knowledge system is available to human adults and infants (even in cultures that don't have a count list), as well as to monkeys, rats, pigeons, and so forth.
Read the rest of this post... | Read the comments on this post...... Read more »
Barth H, Kanwisher N, & Spelke E. (2003) The construction of large number representations in adults. Cognition, 86(3), 201-21. PMID: 12485738
Lipton JS, & Spelke ES. (2003) Origins of number sense. Large-number discrimination in human infants. Psychological science : a journal of the American Psychological Society / APS, 14(5), 396-401. PMID: 12930467
Mechner F. (1958) Probability Relations within Response Sequences under Ratio Reinforcement. Journal of the experimental analysis of behavior, 1(2), 109-21. PMID: 16811206
Hauser, M., Tsao, F., Garcia, P., & Spelke, E. (2003) Evolutionary foundations of number: spontaneous representation of numerical magnitudes by cotton-top tamarins. Proceedings of the Royal Society B: Biological Sciences, 270(1523), 1441-1446. DOI: 10.1098/rspb.2003.2414
Nearly everyone has heard of developmental dyslexia – a learning disorder characterized by poor reading skills despite otherwise sufficient schooling – but have you heard of developmental dyscalculia? Many people have not. Here is part 2 in a week-long series on this lesser-known learning disorder. (See part one, and a companion post on comparative numerical [...]... Read more »
Shalev, R., Manor, O., Kerem, B., Ayali, M., Badichi, N., Friedlander, Y., & Gross-Tsur, V. (2001) Developmental Dyscalculia Is a Familial Learning Disability. Journal of Learning Disabilities, 34(1), 59-65. DOI: 10.1177/002221940103400105
Shalev, R., Auerbach, J., Manor, O., & Gross-Tsur, V. (2000) Developmental dyscalculia: prevalence and prognosis. European Child , 9(S2). DOI: 10.1007/s007870070009
Whether it's a company like BP apologising for causing environmental catastrophe or a political leader expressing regret for her country's prior misdemeanors, it seems there's barely a day goes by without the media watching hawkishly to find out just how the contrite words will be delivered and what effect they'll have on the aggrieved.
Surprisingly, psychology has, until now, paid little attention to what makes for an effective apology. Past studies have tended to focus instead simply on whether an apology was given or it wasn't. Now Ryan Fehr and Michele Gelfand at the University of Maryland have drawn on research in other disciplines, including sociology and law, to explore the idea that apologies come in three forms and that their impact varies according to the character of the victim.
The three apology types or components are: compensation (e.g. I'm sorry I broke your window, I'll pay to have it repaired); empathy (e.g. I'm sorry I slept with your best friend, you must feel like you can't trust either of us ever again); and acknowledgement of violated rules/norms (e.g. I'm sorry I advised the CIA how to torture people, I've broken our profession's pledge to do no harm).
Fehr and Gelfand's hypothesis was that the effectiveness of these different styles of apology depends on how the aggrieved person sees themselves (known as 'self-construal' in the psychological jargon). To test this, the researchers measured the way that 175 undergrad students see themselves and then had them rate different forms of apology. In a follow-up study, 171 more undergrads reported how they see themselves and then they rated their forgiveness of a fictional student who offered different forms of apology after accidentally wiping her friend's laptop hard-drive.
The researchers found that a focus on compensation was most appreciated by people who are more individualistic (e.g. those who agree with statements like 'I have a strong need to know how I stand in comparison to my classmates or coworkers'); that empathy-based apologies are judged more effective by people who see themselves in terms of their relations with others (e.g. they agree with statements like 'Caring deeply about another person such as a close friend is very important to me'); and finally, that the rule violation kind of apology was deemed most effective by people who see themselves as part of a larger group or collective (e.g. they agree with 'I feel great pride when my team or work group does well' and similar statements). These patterns held regardless of the severity of the misdemeanour, as tested by using different versions of the disk-wipe scenario in which either an hour's or several weeks' worth of data were lost.
The message, the researchers said, is that when apologising you should consider your audience. 'This need to meta-cognize about what a victim is looking for in an apology is particularly important when victims' and offenders' worldviews diverge,' they added. Of course, if in doubt about the character of your victim or victims, the researchers said that 'detailed apologies with multiple components are in general more likely to touch upon what is important to a victim than brief, perfunctory apologies. Offenders should therefore offer apologies with multiple components whenever possible.'
Fehr and Gelfand acknowledge their study has limitations, including their reliance on participants imagining fictional scenarios - future research should test out these ideas in the real world. 'By integrating theories of self-construal and apology,' they concluded, 'the current study has shown how the tailoring of apologies to individuals' self-construals can result in increased victim forgiveness.'
Fehr, R., & Gelfand, M. (2010). When apologies work: How matching apology components to victims’ self-construals facilitates forgiveness. Organizational Behavior and Human Decision Processes, 113 (1), 37-50 DOI: 10.1016/j.obhdp.2010.04.002
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Fehr, R., & Gelfand, M. (2010) When apologies work: How matching apology components to victims’ self-construals facilitates forgiveness. Organizational Behavior and Human Decision Processes, 113(1), 37-50. DOI: 10.1016/j.obhdp.2010.04.002
Brain protein MeCP2 in the spotlight.
Dr. Edward Sellers, former director of the psychopharmacological research program at the University of Toronto’s Addiction Research Foundation once said to me: “Every cell, every hormone, every membrane in the body has got genetic underpinnings, and while many of the genetic underpinnings are similar in people, in fact there are also huge differences. So on one level, the fact that there is a genetic component to addiction is not very surprising. What is surprising is that you could ever have it show up in a dominant enough way to be something that might be useful in anticipating risk.”
If there existed a set of genes that predisposed people to alcoholism, and possibly other addictions, then these genes had to control the expression of something specific. That’s what genes did. However, back in the 1990s, addiction researchers could not even agree on the matter of where they should be looking for such physical evidence of genetic difference. In the brain? Among the digestive enzymes? Blood platelets? A gene, or a set of genes, coding for…what? What was it they were supposed to be looking for?
What set of genes coded for addiction?
Something about modern genetic research breeds a strong jolt of excitement. There is the promise of sudden discoveries, headlines, and great leaps forward toward cures for stubborn diseases. Even the most sober scientists seem to get enthused about gene hunting. The idea of curing a disease by locating a defective gene and repairing it is one of the brightest and fondest hopes in medicine. At least 3,000 medical disorders, including diabetes, cystic fibrosis, and some forms of Alzheimer’s are inherited diseases caused by defective genes passed on from generation to generation. But the premature announcements and retractions involving genes for everything from drinking to shyness has brought a hard-won maturity to the field.
These days, the hunt for evidence of genes influencing addiction is drilling very deeply into the molecular underpinnings of neural activity, in a wide-ranging effort to sort out the variety of gene interactions involved in the genetic propensity for alcoholism and other addictions. Work done at the Scripps Research Institute in Florida, funded by the National Institute on Drug Abuse (NIDA) and published in Nature Neuroscience, recently shone a spotlight on a gene responsible for making a particular protein—MeCP2—needed for normal development of nerve cells in the brain. This gene for methyl CpG binding protein 2 is best known as the gene responsible for a rare genetic brain disorder called Rett syndrome.
Researchers at Scripps discovered that cocaine increased levels of this regulatory protein in the brains of rats. So did flouxetine , better known as Prozac, suggesting that the serotonergic system may be involved. “At that point,” according to lead author Paul Kenny, “we wanted to know if this increase was behaviorally significant—did it influence the motivation to take the drug?” Evidently it did. The higher the levels of MeCP2 in the brain, the higher the rats’ motivation to consume cocaine. When the researchers disrupted the expression of MeCP2 with a virus, the rats showed less interest in cocaine.
This is the first evidence that MeCP2 plays some as yet unexplained role in regulating vulnerability to cocaine addiction. Earlier this summer, investigators reported in Nature that another regulatory molecule known as MiRNA-212—a type of RNA involved in gene regulation--had the opposite effect, lessening the test animals’ interest in cocaine. The balancing act between MeCP2 and MiRNA-212 may help explain “the molecular mechanisms that control the transition from controlled to compulsive cocaine intake,” according to the paper, although the mechanisms that regulate this balance are not known.
One strong piece of evidence for this regulatory feedback loop was the finding that, while MeCP2 blocked miR-212 expression, the opposite was also true. “We still don’t know what exactly influences the activity levels of MeCP2 on miR-212 expression,” according to Kenny. “Now we plan to explore what drives it—whether it’s environmentally driven, and if genetic and epigenetic influences are important.” (For more on MeCP2, check this Lab Spaces post.)
NIDA director Nora Volkow said in an NIH press release that the work on MeCP2 “exposed an important effect of cocaine at the molecular level that could prove key to understanding compulsive drug taking.”
Graphics Credit: http://www.labspaces.net/
Im, H., Hollander, J., Bali, P., & Kenny, P. (2010). MeCP2 controls BDNF expression and cocaine intake through homeostatic interactions with microRNA-212 Nature Neuroscience DOI: 10.1038/nn.2615... Read more »
Im, H., Hollander, J., Bali, P., & Kenny, P. (2010) MeCP2 controls BDNF expression and cocaine intake through homeostatic interactions with microRNA-212. Nature Neuroscience. DOI: 10.1038/nn.2615
MacLean (2010) confirms that combat veterans can be disabled for life by their battlefield experiences, regardless of whatever 'pre-combat characteristics' they might have possessed.... Read more »
MacLean, A. (2010) The Things They Carry: Combat, Disability, and Unemployment among U.S. Men. American Sociological Review, 75(4), 563-585. DOI: 10.1177/0003122410374085
Nearly everyone has heard of developmental dyslexia – a learning disorder characterized by poor reading skills despite otherwise sufficient schooling – but have you heard of developmental dyscalculia? Many people have not. Today begins a week-long series on this lesser-known learning disorder. First, we’ll consider some potentially innate mechanisms of numerical cognition that give rise [...]... Read more »
Xu, F. (2000) Large number discrimination in 6-month-old infants. Cognition, 74(1). DOI: 10.1016/S0010-0277(99)00066-9
Lipton JS, & Spelke ES. (2003) Origins of number sense. Large-number discrimination in human infants. Psychological science : a journal of the American Psychological Society / APS, 14(5), 396-401. PMID: 12930467
Geary DC. (1995) Reflections of evolution and culture in children's cognition. Implications for mathematical development and instruction. The American psychologist, 50(1), 24-37. PMID: 7872578
I will be reposting some dog-related posts from the archives in the coming few weeks as I prepare for the course I'm teaching this semester on dog cognition. Please let me know if you find something inaccurate or unclear.
Domesticated dogs seem to have an uncanny ability to understand human communicative gestures (see here). If you point to something the dog zeroes in on the object or location you're pointing to (whether it's a toy, or food, or to get his in-need-of-a-bath butt off your damn bed and back onto his damn bed). Put another way, if your attention is on something, or if your attention is directed to somewhere, dogs seem to be able to turn their attention onto that thing or location as well.
Amazingly, dogs may be better at this than primates (including our nearest cousins, the chimpanzees) and better than their nearest cousins, wild wolves.
And so it was that biological anthropologist Brian Hare, director of the of Duke University Canine Cognition Center wondered: did dogs get so smart because of direct selection for this ability during the domestication of dogs, or did this apparent social intelligence evolve, in a sense, by accident, because of selection against fear and aggression?
Remember the Russian foxes? In that experiment, by selecting for tameness and against fear and aggression, a number of other seemingly unrelated traits began to express themselves in the domesticated foxes. They appeared to enjoy hanging out with humans. They sniffed and licked their caretakers. They wagged their tails when excited (remember this video?). Their tails got curlier and shorter. Their ears got floppier. Their skull-size (relative to body-size) increased. Their fur coloration patterns changed. They also showed evidence of physiological changes, such as in the pituitary-adrenal pathway.
Figure 1: Time for a picture of a dog. Some dogs are clearly smarter than others.
Hare and his colleagues pitted these two hypotheses against eachother. The "Selection for Communication" Hypothesis suggests that predicting and manipulating human behavior by reading human communicative signals (such as eye gaze or arm pointing) was explicitly selected in the domestication of dogs. Those dogs who were most skilled at comprehending such gestures were more likely to survive and reproduce. The "Correlated By-Product" Hypothesis predicts that the ability to read human communicative gestures was not directly selected for during the domestication of dogs. Instead, fear and aggression were selected against (which is the same as saying that tameness was selected), and as a result, those individuals with less stress, who had positive interactions with humans had the highest evolutionary fitness. Moreover, those same dogs, because of the "changes responsible for [their] high levels of tameness... were no longer constrained [by fear or disinterest, for example] in applying previously existing social problem-solving skills to humans" in interactions between the two species. Read the rest of this post... | Read the comments on this post...... Read more »
Hare, B., Plyusnina, I., Ignacio, N., Schepina, O., Stepika, A., Wrangham, R., & Trut, L. (2005) Social Cognitive Evolution in Captive Foxes Is a Correlated By-Product of Experimental Domestication. Current Biology, 15(3), 226-230. DOI: 10.1016/j.cub.2005.01.040
Over thirty years ago, Richard Dawkins coined the term “meme” in his classic book The Selfish Gene. A meme was analogous to a gene. A gene is a physical replicator that multiplied itself (but with variations), in such a way that permitted selection and evolution. A meme, Dawkins wrote, was an intellectual replicator that could also multiple itself, creating variants as it did so, allowing evolution.
About two years ago. Susan Blackmore complained that people weren’t taking mimetics seriously, and I argued that mimetics is nowhere near being serious science.
A new paper by Cardoso and Atwell uses the meme concept in describing birdsong. On the face of it, bird song is not a bad model to use the meme concept. Some songs are easily measured; and there are distinct varieties, that are subject to some variation as they are learned.
Cardoso and Atwell looked at the songs of dark eyed juncos (Junco hyemalis) in California, where there has only been a population for about 30 years. In that time, their songs have gotten higher in pitch, which is something that tends to happen to birds in environments with lots of human created sound. They compared those to an older, more established population further from urban centers.
They’re trying to figure out if the number of modifications the birds introduce is enough to explain the change in the songs (like mutation for a gene). If it isn’t, that suggests there is another process going on, like a selective process as birds discard some songs.
If I’m understanding the authors right*, the birds change their songs slightly, but those modifications are only enough to account for about half the difference between the two populations.
The remaining difference between the two populations, they argue, came because the high frequency songs “outcompeted” the low frequency songs. But I think* they are also arguing that no selection for high pitched songs is going on right now. They say this because they reckon that if there was selection going on right now, it would be expressed by more males learning, and singing, higher-pitched songs than lower pitched songs – which isn’t the case.
In other words, the song situation appears to have stabilized. This is slightly frustrating for me as a reader, because I was hoping to get a sense of the process of song change, but it seems most of the action happened decades ago.
What I am not seeing is how characterising songs as memes leads to distinctly different hypotheses or explanations than plain old learning and communication theory does. Cardoso and Atwell are able to couch their descriptions in terms of mimetics, but I would be more impressed if they were about to use mimetics to make a explicit prediction that differed from some theory.
I haven’t changed my mind about mimetics yet.
* I have to put in that caveat that I may be getting it wrong, because this paper assumes a lot of background knowledge. For instance, me being a novice in birdsong, it’s not clear how you would group over 1,000 sound recordings into about 100 song types, or memes. There several points like that in this paper.
Cardoso G, & Atwell J. 2010. Directional cultural change by modification and replacement of memes. Evolution. DOI: 10.1111/j.1558-5646.2010.01102.x
Photo by pheanix300 on Flickr, used under a Creative Commons license.... Read more »
Cardoso, G., & Atwell, J. (2010) DIRECTIONAL CULTURAL CHANGE BY MODIFICATION AND REPLACEMENT OF MEMES. Evolution. DOI: 10.1111/j.1558-5646.2010.01102.x
OK, so when was the last time you saw a public health campaign which tried to increase physical activity levels by targeting intrinsic motivations to exercise? I personally cant think of any I've seen! Motivation for exercise can be defined as intrinsic or extrinsic. Intrinsic motivations for exercise are behaviours that are performed for the satisfaction gained in the activity itself. Deci and Ryan (1985) argue that intrinsic motivations are commonly those of competency, interest and enjoyment. I exercise because it makes me feel good and I enjoy it, however most campaigns to increase PA are of the loose weight and keep healthy variety. Deci and Ryan (2000) identified that activities which are pursued primarily for being enjoyable and interesting are known to be intrinsically motivating the reward is taking part in the activity itself! Extrinsic motivations for exercise include are those behaviours which are performed rewards that are external. This would include outcomes such as getting fitter, improving appearance, weight loss or ‘toning up’. This is taking part in an activity for reasons other than the activity itself (Taylor, Ntoumanis, Standage & Spray, 2010). This where almost all public campaigns to increase physical activity are targeted with limited success. Ryan et al., (1997) examined exercise adherence with regard to intrinsic and extrinsic motivation. Although motivation to exercise includes both intrinsic and extrinsic elements Ryan et al., (1997) reported that body related (extrinsic) motivations were negatively related to hours per week exercise participation and workout length, whereas enjoyment and competence were positively to these measures. It would appear that intrinsic motivation is a requirement of continued exercise adherence and may become even more important as the timeframe of the adherence behaviour continues. Even motivations for PA such as aiming to lead a healthy lifestyle would be viewed as extrinsic as they are being pursued for reasons other than performing the activity itself. This is important as the public messages to encourage the uptake of physical activity and exercise are generally aimed at extrinsic motivators, i.e. weight loss, to improve body image and to improve health status. Very few public health messages try to convince the audience that physical activity is fun and perhaps an end in itself. Sports participation has been shown to be more likely to be motivated by intrinsic motivators such as fun and enjoyment, whereas exercise is more often linked to extrinsic motivators such as weight loss, appearance and stress management and that this difference leads to different rates of adherence (Kilpatrick et al., 2005). Most participants in sport and exercise are likely to be motivated both intrinsically and extrinsically to a greater or lesser degree. Researchers argue that for long term adherence extrinsic motive must be replaced by intrinsic motives i.e. enjoyment and competency or individuals are unlikely to persist in behaviour (Brawley & Vallerand, 1984: Wankel, 1993). Many exercise interventions appear to attempt to engage individuals only at a level which appeals to extrinsic motives only such as improving fitness or appearance; this in light of the previous research has implications the success of campaigns tartgeting only intrinsic motivations for exercise. Ryan, R., Frederick, C., Lepes, D., Rubio, N., & Sheldon, K. (1997). Intrinsic motivation and exercise adherence. International Journal of Sport Psychology, 28, 335-354.Ryan, R., & Deci, E. (2000). Self-determination theory and the facilitation of intrinsic motivation, social development, and well-being. American psychologist, 55(1), 68-78.Taylor IM, Ntoumanis N, Standage M, & Spray CM (2010). Motivational predictors of physical education students' effort, exercise intentions, and leisure-time physical activity: a multilevel linear growth analysis. Journal of sport & exercise psychology, 32 (1), 99-120 PMID: 20167954... Read more »
Taylor IM, Ntoumanis N, Standage M, & Spray CM. (2010) Motivational predictors of physical education students' effort, exercise intentions, and leisure-time physical activity: a multilevel linear growth analysis. Journal of sport , 32(1), 99-120. PMID: 20167954
The latest issue of the Journal of Neuroscience contains an interesting article by Ecker et al in which the authors attempted to classify people with autism spectrum disorder (ASD) and health controls based on their brain anatomy, and report achieving “a sensitivity and specificity of up to 90% and 80%, respectively.” Before unpacking what that [...]... Read more »
Ecker C, Marquand A, Mourão-Miranda J, Johnston P, Daly EM, Brammer MJ, Maltezos S, Murphy CM, Robertson D, Williams SC.... (2010) Describing the brain in autism in five dimensions--magnetic resonance imaging-assisted diagnosis of autism spectrum disorder using a multiparameter classification approach. The Journal of neuroscience : the official journal of the Society for Neuroscience, 30(32), 10612-23. PMID: 20702694
As I’m getting on in my study I’ve found that people (outside of uni) treat me as something of an expert on all things ‘brain’. I don’t push this image because, frankly, I’m not an expert in anything. Though most of the time I can find some element of their question I can answer, however [...]... Read more »
Sewell RA, Halpern JH, & Pope HG Jr. (2006) Response of cluster headache to psilocybin and LSD. Neurology, 66(12), 1920-2. PMID: 16801660
I’m pretty sure most clinicians want to believe that they treat people with equal respect, that they listen carefully and respond with empathy when a person has concerns about their health. At the same time I’ve listened to many people with chronic pain describe how they’ve had trouble feeling heard, how they can feel like … Read more... Read more »
Gulbrandsen, P., Madsen, H., Benth, J., & Lærum, E. (2010) Health care providers communicate less well with patients with chronic low back pain – A study of encounters at a back pain clinic in Denmark. Pain, 150(3), 458-461. DOI: 10.1016/j.pain.2010.05.024
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