Month: April 2011

Regard thyself and put down the smoke stick

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As many a former smoker will probably attest, quitting cigarettes ranks high in the hard-to-kick category. I made several unsuccessful attempts before finally kicking the habit after a 10 year pack-a-day run. Ultimately what worked for me was to go cold turkey, but there were perhaps other alternatives which I might have tried. In a paper from Nature Neuroscience, researchers from University of Michigan provided participants with interventions involving individually tailored messages* designed to encourage quitting and found that participants’ brain activity while listening to the messages predicted how likely they would be to successfully quit smoking.

*Tailored messages are statements about an individuals’ issues and thoughts about quitting smoking, derived from pre-screen interviews with them. e.g., “You are worried that when angry or frustrated, you may light up”.

Here’s the premise: Anti-smoking messages custom made for an individual can be more effective than generic ones, but only if said individual processes those messages in a self directed manner. Past research has shown a specific set of neural regions – primarily the mPFC and precuneus/posterior cingulate – to be associated with self referential thinking. Therefore, researchers hypothesized, activity in these brain regions while processing tailored anti-smoking messages might predict the likelihood of quitting.

The Study
The experiment was carried out over three days with a follow-up visit four months later.

Day 1: 91 participants completed a health assessment, demographic questionnaire and a psychosocial characteristics scale related to quitting smoking. Responses were then used to create smoking cessation messages tailored to each individual.
Day 2: Participants went into scanner and performed 2 fMRI tasks: The first task had participants listen to anti-smoking messages of three different types: personally tailored anti-smoking, non-tailored anti-smoking and neutral.

Here are some examples of what they heard:

Tailored messages
A concern you have is being tempted to smoke when around other smokers.
Something else that you feel will tempt you after you quit is because of a craving.
You are worried that when angry or frustrated, you may light up.
Untailored messages
Some people are tempted to smoke to control their weight or hunger.
Smokers also light up when they need to concentrate.
Certain moods or feelings, places, and things you do can make you want to smoke.
Neutral messages
Oil was formed from the remains of animals and plants that lived millions of years ago.
Sighted in the Pacific Ocean, the world’s tallest sea wave was 112 feet.
Wind is simple air in motion. It is caused by the uneven heating of the earth’s surface by the sun.

Then, participants completed a self appraisal task to identify brain regions active during self relevant thought processes. In this task, participants saw adjectives appear on the screen and had to either rate how much the adjective described them or whether the adjective was positive or negative.

Day 3: Participants completed a web-based smoking cessation program and were instructed to quit smoking. (They were given a supply of nicotine patches to get themselves started)

Results
Behavioral
Experimenters checked in with subjects four months later to see if they were abstaining from smoking. Out of 87 who participated in the smoking cessation program, 45 were not smoking, while 42 were still (or had quit briefly and restarted) smoking.

Subjects were given a surprise memory test for the anti-smoking messages they’d received four months prior and remembered self relevant, tailored messages most well. However, their memory performance was not related to whether they successfully quit smoking.

fMRI
As for the fMRI data, experimenters used a mask of tailored vs. untailored message conditions AND self-appraisal to identify the region common to both processes. This seems like a mild case of double dipping, no? That is, finding a brain region that responds to the condition of interest (in this case, voxels more active in tailored vs. untailored conditions) and then using the same data to test the hypothesis. Ideally, the ROI would be obtained independently of the main task.

A blow by blow on the different contrasts of interest:

1. Researchers looked at brain regions more active during tailored vs. untailored messages and found differential activation in the regions below.

There are, I think, some problems here; mainly, that the task differences for processing tailored vs non-tailored statements may extend beyond self relevant thinking to (1) memory processes employed in processing either category of stimuli; that is, episodic (tailored) vs. semantic (non-tailored), (2) cognitive effort, (3) elicitation of visual vs. non-visual memory, (4) processing fluency and (5) affect or reward responses. Thus, the difference in brain activation found in this task might reflect something other than just self referential processing.

2. The localizer task (used to isolate neural areas involved in self appraisal) had participants process adjectives either by relating them to self or by judging their affective value. This suggests an alternative explanation for the categorical contrast in that it isn’t specific to self per se, but really more specific to people vs. non-people. A more widely used version of this task has participants process adjectives with regards to self or an other. As a further control, a third condition is often included in which participants identify whether words are in upper case or lower case. The contrast applied is (self – control) – (other – control). It’s not clear why the researchers chose the task they did, which seems significantly noisier.

Here’s the contrast from the present study:

And here’s a contrast from another study (Jenkins 2010) that looked at three different types of self-referential processing.

Although roughly similar, the current study shows cortical midline activation seems to be much more dorsal than that found in Jenkins (2010). Using an ROI derived from this localizer task to correlate neural activity in tailored vs. untailored statements with quitting led to a non-significant result (from supplementary materials). This could explain why the researchers used the composite mask to define the ROI.

3. Again, the primary ROI was defined as a composite of overlapping regions between the self reference task AND the tailored vs. untailored statements task, which was used to compare neural activity with quitting behavior. They found that activity in these regions – which included dmPFC, precuneus and angular gyrus – during tailored smoking cessation messages predicted the likelihood of successfully abstaining from smoking. dmPFC and precuneus activation also individually predicted smoking cessation success, although angular gyrus did not.

This study provides clear evidence that participants processed tailored vs. non-tailored messages about smoking differently, and that this difference corresponded to their ability to stop smoking. However,
(1) neither task effectively isolates self referential processing,
(2) the region of activation was much more dorsal than that usually found in this literature (Northoff & Bermpohl, 2004; Schneider et al.,2008; Uddin, Iacoboni, Lange, & Keenan, 2007; Gillihan & Farah, 2005),
(3) an independently obtained ROI yielded insignificant results and
(4) mPFC and precuneus subserve an untold number of cognitive processes beyond self reflection.

Therefore, it seems a bit of a stretch to claim the neural activation found in this study is indicative of self referential processing.

References
Chua HF, Ho SS, Jasinska AJ, Polk TA, Welsh RC, Liberzon I, & Strecher VJ (2011). Self-related neural response to tailored smoking-cessation messages predicts quitting. Nature neuroscience, 14 (4), 426-7 PMID: 21358641

Jenkins AC, & Mitchell JP (2010). Medial prefrontal cortex subserves diverse forms of self-reflection. Social neuroscience, 1-8 PMID: 20711940

Northoff, G. (2005). Emotional-cognitive integration, the self, and cortical midline structures Behavioral and Brain Sciences, 28 (02) DOI: 10.1017/S0140525X05400047

Gillihan, S., & Farah, M. (2005). Is Self Special? A Critical Review of Evidence From Experimental Psychology and Cognitive Neuroscience. Psychological Bulletin, 131 (1), 76-97 DOI: 10.1037/0033-2909.131.1.76

SCHNEIDER, F., BERMPOHL, F., HEINZEL, A., ROTTE, M., WALTER, M., TEMPELMANN, C., WIEBKING, C., DOBROWOLNY, H., HEINZE, H., & NORTHOFF, G. (2008). The resting brain and our self: Self-relatedness modulates resting state neural activity in cortical midline structures Neuroscience, 157 (1), 120-131 DOI: 10.1016/j.neuroscience.2008.08.014

UDDIN, L., IACOBONI, M., LANGE, C., & KEENAN, J. (2007). The self and social cognition: the role of cortical midline structures and mirror neurons Trends in Cognitive Sciences, 11 (4), 153-157 DOI: 10.1016/j.tics.2007.01.001

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Revisiting a classic finding: the fallacy of the hot hand

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(*In honor of the upcoming NBA playoffs, a brief post on, for my money, the big paradox of professional basketball: the myth of the hot hand.)

Despite a long and fruitful career full of notable findings, Cornell psychologist Thomas Gilovich is perhaps most well known for a study he conducted with psychologists Amos Tversky and Robert Vallone 25 years ago when he presented a devastating debunking of the sports phenomena known as the “hot hand.”

The hot hand refers to the belief that success in basketball (and elsewhere) is self perpetuating. That is, a player can “get into a groove” after making a couple of shots such that making a shot leads to the higher likelihood of making the next shot. String together a bunch of these and you’ve got yourself a hot hand. Tune into any basketball game and you’ll inevitably hear an announcer say, “he’s in the zone” or “he can’t miss right now” about a player with a hot hand.

If this is true, one should look at a set of all made shots and all missed shots for some entity, such as one team for an entire year, and see that players made more shots after hits than they did after misses. Gilovich and his colleagues did just that, and that’s not what they found. They found that a player was just as likely to miss as make a shot after a previous make. But what about the possibility that opposing defense becomes tougher after a guy has made a few? Or what if he starts taking more difficult shots?

To control for these possibilties, they looked at free throws, which control for both of those factors in that there is no defensive pressure and shots are always taken from the same distance. A look at two seasons worth of free throws from the Boston Celtics showed second shots were completely independent of first shots. That is, if a player made the first free throw, he was no more likely to make the second one than if he missed the first one.

As a sports fan, I’ve always had a difficult time accepting this. (I’m not alone: the famed coach Bobby Knight responded to the study by saying, ” … there are so many variables involved in shooting the basketball that a paper like this really doesn’t mean anything.” Red Auerbach was even more blunt: “Who is this guy? So he makes a study? I couldn’t care less.” ) It just seems so counterintuitive that success or failure wouldn’t have some systematic effect on subsequent performance.

It’s a seeming truism that professional athletes (and performing artists, for that matter) perform best when they’re not thinking about how they’re playing. And it’s widely known by sports psychologists that thinking too much about one’s form in any given sport, whether it be shooting the basketball or attempting to sink a putt, can have deleterious effects on performance. So it seems plausible to imagine that success (or lack thereof) on the basketball court could alter one’s mental state in a way that could systematically alter performance. But, that’s not what the data says.

In the two decades plus since Gilovich, Vallone and Tversky’s seminal paper, the hot hand fallacy has been subject to a great deal of scrutiny and doubt, but the original finding has generally held up. One study controlled for time between shots but still found no evidence for the hot hand (Adams, 1992). Others have suggested that statistics are insufficient to handle the complexity of the game (Larkey, 1989). In 2009, John Huizinga from the Chicago Booth School of Business and Sandy Weil analyzed almost a million shots from 49 star players (unpublished; here for more details) and found, contrary to the existence of the hot hand, that NBA stars were more likely to miss after a made shot than after a miss. According to their analysis, this was more likely to happen after jump shots than non-jump shots (layups or dunks).

The implications of all this are that teams shouldn’t be looking to feed the ball to a guy just because he’s made a few in a row. But despite the ample support that hot hands don’t exist, you won’t have any easy time convincing many players or coaches of this.

A post game synopsis from an LA Lakers game last fall:

Jackson’s rationale for leaving Vujacic out entails the fact that Shannon Brown scored 16 points on six of nine shooting in 21 minutes. That led Jackson to “ride the hot hand,” as he called it, even if he had planned for Vujacic to defend against Houston guard Kevin Martin…

Even Phil Jackon, probably the most successful NBA coach in modern times, cites “the hot hand” as basis for his personnel decisions.

In Gilovich’s book summarizing the work, How We Know What Isn’t So, he talks to former NBA star World B. Free about the hot hand. “If I’m on, I find that confidence just builds . . . you feel nobody can stop you. It’s important to hit that first one, especially if it’s a swish. Then you hit another, and . . . you feel like you can do anything.”

This line of thinking, that success breeds success, is certainly feasible in many aspects of one’s life. Financial success can lead to further success, as profit can lead to more profit through increased capital. In one’s professional life, success can have a powerful effect on how one is perceived by others and promote increased success through an enhanced reputation. But, on the basketball court, the implications are quite clear. There are many factors that go into deciding – say, during crunch time of a close game – who should get the ball. A simple heuristic might be to give the ball to the guy with the highest shooting percentage. But what if he’s having an off night due to injury? Or being consistently double teamed? Perhaps your second best shooter gets the call. Many factors might inform the decision. But, according to everything the data is telling us, the “hot hand” should not be one of them.

References
GILOVICH, T. (1985). The hot hand in basketball: On the misperception of random sequences Cognitive Psychology, 17 (3), 295-314 DOI: 10.1016/0010-0285(85)90010-6

Adams, R. (1992). The “Hot Hand” Revisited: Successful Basketball Shooting as a function of intershot interval.Perceptual and Motor Skills, 74 (3) DOI: 10.2466/PMS.74.3.934-934

Larkey, P. D., Smith, R. A., & Kadane, J. B. (1989). It’s okay to believe in the ‘‘hot hand’’.
Chance: New Directions for Statistics and Computing, 2, 22 – 30.

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Disorder increases Stereotyping and Discrimination

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The study previously summarized in this post was formally retracted in December 2011.
The retraction is the first in what is expected to be a slew of retractions of papers by lead author Diderik Stapel based entirely on falsified data.

Stapel was removed from his position at Tilburg University in November 2011 after an investigative committee at the university concluded he faked data on as many as dozens of papers over the past several years. Read a concise summary of how Stapel pulled this all off here.

Stapel’s mea culpa is below. Note that while his apology seems sincere, he can’t resist blaming his actions on the field itself, the pressure to publish often, etc. And he says he didn’t do it for selfish ends. Sorry buddy, but everyone else in the field is under the same pressure as you were but they don’t go around publishing papers based on fake data. They work their asses off and actually collect data (arguably the hardest part of the whole endeavor) before writing a study up and submitting it. What you did was for entirely selfish reasons. You did it to advance your career beyond what would have been possible if you played by the rules.

“I failed as a scientist. I adapted research data and fabricated research. Not once, but several times, not for a short period, but over a longer period of time. I realize that I shocked and angered my colleagues, because of my behavior. I put my field, social psychology in a bad light. I am ashamed of it and I deeply regret it.
… I think it is important to emphasize that I never informed my colleagues of my inappropriate behavior. I offer my colleagues, my PhD students, and the complete academic community my sincere apologies. I am aware of the suffering and sorrow that I caused to them.
… I did not withstand the pressure to score, to publish, the pressure to get better in time. I wanted too much, too fast. In a system where there are few checks and balances, where people work alone, I took the wrong turn. I want to emphasize that the mistakes that I made were not born out of selfish ends.”

UPDATE (2.26.2012): Tilburg University is conducting an investigation of Stapel’s entire body of work and won’t announce verdicts on specific studies until after the investigation in concluded.

Mirror Neurons and Mentalizing

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Perhaps few findings in the cognitive sciences have received more press in recent years than the discovery by Rizolatti and colleagues in macque monkeys of mirror neurons; that is, neurons that preferentially activate both when a monkey performs some action and when observing someone else perform the same action. There is evidence that these neurons exist in humans, although it’s indirect (however, see Keysers 2010). They’ve quite captivated the publics’ attention, these crafty little neurons.

The mirror neuron system is thought to help primates, non-human and human, understand what others are doing by simulating the motor plan of an observed action and also allowing for prediction of the most likely outcome of an observed action. In other words, mirror neurons are sensitive both to actions and outcomes, and to some extent, inferring the why behind the what. Many have suggested that they play a significant role in comprehending mental states and empathic processes. But it’s in regards to these latter claims where the evidence is not as clear.

So, how does the brain intuit others’ inherently unobservable mental states in the absence of biological action? Much of the research evidence points to the mentalizing system, also known as the theory-of-mind network, as the neural network tasked to the job (see meta-analysis by Van Overwalle and Baetens, 2009). Anatomically speaking, these networks are distinct, with the mirror neurons located primarily in the ifraparietal sulcus, superior temporal sulcus and the prefrontal cortex, while the mentalizing system constitutes a distinct set of brain regions that lie along the cortical midline and in the temporal lobes, including the mPFC, TPJ, temporal poles, PCC and posterior STS.

One of the big challenges in this area of research is in designing tasks that are able to effectively disentangle processing of motor action from mentalizing. This is quite a challenge because it’s difficult to know what kind of mental process participants are applying to any given set of social stimuli. Do participants engage in higher-order abstract mentalizing automatically, and even when the stimuli might not necessarily demand it? How can we know what mental process subjects are engaging in? In other words, how might one capture the distinction between perceiving what others are doing vs. obtaining a more abstract representation of why they might be doing it?

UCLA’s Bob Spunt and colleagues (2011) designed a study that would attempt to do just that. They had participants observe short video clips of a human performing an action and directed the participants, in the scanner, to covertly describe each video clip in terms of (1) what an actor was doing, (2) why he was doing it, (3) how we was doing it or (4) to just passively view the video. They were to start the process of covert description once the video started playing, begin their description with the word “he” (e.g. he is reading) and to press a button once they were done.

(Thanks to the researchers for providing the video)

For example, in the above example, participants might have covertly described that the man is reading (WHAT), that he wants to learn or is bored (WHY), or that he is flipping pages or gripping the book (HOW).

This had the effect of creating three levels of mentalizing “depth” while holding the action component constant. If the mirror neuron network was involved in the mentalizing process, then one would expect to see neural activation increases in the mirror neuron network covarying with the increase in participants presumed mentalizing about the actor. And if the mirror neuron network was involved in mentalizing, then one would expect to see increased activations in neural regions which have been previously suggested to contain mirror neurons.

Results
In support of the theory that mirror neurons don’t play a significant role in mentalizing, the researchers found no increase in the mirror neuron network in response to increases in mentalizing. But they did find increased activation in brain regions associated with mentalizing, including dorsal and ventral medial pFC, posterior cingulate cortex, and the temporal poles.

Conclusion
The study does provide another piece of support to the position that although the mirror neuron system might be necessary in understanding actions of the body, it’s not sufficient to explain the cognitive processes required to infer unobservable mental states.

References
Spunt, R., Satpute, A., & Lieberman, M. (2011). Identifying the What, Why, and How of an Observed Action: An fMRI Study of Mentalizing and Mechanizing during Action Observation Journal of Cognitive Neuroscience, 23 (1), 63-74 DOI: 10.1162/jocn.2010.21446

Keysers, C., & Gazzola, V. (2010). Social Neuroscience: Mirror Neurons Recorded in Humans Current Biology, 20 (8) DOI: 10.1016/j.cub.2010.03.013

Van Overwalle F, & Baetens K (2009). Understanding others’ actions and goals by mirror and mentalizing systems: a meta-analysis. NeuroImage, 48 (3), 564-84 PMID: 19524046

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Soap, Sex and the Dirty Liberal

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Do you find Rush Limbaugh more palatable after vs. before taking a bath? Might you be more inclined to linger on the Bill O’Reilly Show while channel flipping in a recently-mopped and cleaned room compared to a dirty and disheveled one?

Perhaps you just might. At least, that’s what recent research from Cornell’s Erik Helzer and David Pizarro suggests. Their just published study showed that reminding people of physical cleanliness made them report being more politically conservative and also led them to make harsher moral judgments when considering mildly perverted sex acts.

The study builds upon work showing links between moral judgment and the subjective experiences of bodily purity and visceral disgust. Recent studies have shown that individuals who experienced disgust in response to foul odors or by sitting at a dirty desk, judged the moral transgressions of others far more harshly compared to controls. The general idea behind these and other studies is that moral judgments are in part based on emotional responses which originally evolved for other purposes. For example, visceral disgust — say, the kind one might experience when smelling rotten meat — likely evolved as a means of detecting and avoiding harmful pathogens. The argument, as it goes, suggests that self-reported moral disgust responses to, for example, a visible display of homosexual affection (two men kissing) could be subserved by the same system from which “visceral disgust” responses emerge. The current study builds on this work with a crafty two-part experiment.

In the first study, participants were approached in the hallway of a campus building and asked to complete a questionnaire, which asked three questions about political orientation. Participants were instructed to stand either near a hand sanitizing station (the experimental condition) or step over to a wall where there was no hand sanitizer nearby (the control condition) to complete the questionnaire. Those who stood near the hand sanitizing station rated themselves as being more conservative than the control group.

In the second study a wall sign commanding researchers to “use hand wipes” before typing at a computer served as a reminder of cleanliness. Additionally, while the moral judgement task was introduced, participants were asked to use a hand wipe before starting. In the control condition, there was no sign and subjects weren’t asked to wipe their hands. First, participants filled out the political orientation questionnaire from experiment 1. As in the first study, participants in the cleanliness condition rated themselves as more conservative. Then participants engaged in the moral judgment task in which they were asked to rate their moral approval of sex-related items, such as:

“A woman enjoys masturbating while cuddling with her favorite teddy bear”
“After a late-term miscarriage, a woman asks her doctors to take a picture of her cradling the miscarried fetus.” (phew!)

Participants who received the cleanliness reminder issued harsher moral judgments of sexual acts than the control group. As a within-group control, both groups were also asked to rate their level of approval of non-sexual but purity related items such as “As a practical joke, a man unwraps his office mate’s lunch and places it in a sterilized bed pan” and non-sexual, non-purity related items that described people lying on their taxes, or forging a reference letter. For these latter two groups of items, there was no difference between control and experimental groups. Only the sexual items were rated more harshly by those in the “cleanliness” condition. In sum, reminders to maintain cleanliness led to increased conservativeness and harsher moral judgments for sexual violations of purity but not for non-sexual and/or non-purity related violations.

The paper adds to the growing body of work supporting the idea that moral condemnation may have evolved by piggybacking onto evolutionarily older systems originally dedicated mainly to survival via “literal” pathogen avoidance and concern with personal cleanliness and only later being adapted for a more uniquely human purpose. One big question that emerges from this work is: what comes first? The cognitive disposition or the ideology? The author’s suggest that the evidence supports a bidirectional explanation. Beyond that it’s mostly speculation.

Also unclear is the question of the relationship between moral condemnation and moral behavior. Does one predict the other? Conservatives often describe themselves as adhering to higher moral standards when it comes to sex than liberals. And they tend not to be supportive of “alternative” lifestyles, especially romantic relationships between homosexuals. Conversely, most liberals take pride in their embrace of a wider range of lifestyle choices and more progressive sexual attitudes. But, this is not to suggest that either conservatives’ or liberals’ attitudes necessarily maps directly on to their behavior. People sometimes say the wrong thing and do the right thing. Or, conversely, say the right thing and do the wrong thing.

Reference

Helzer EG, & Pizarro DA (2011). Dirty Liberals!: Reminders of Physical Cleanliness Influence Moral and Political Attitudes. Psychological science : a journal of the American Psychological Society / APS PMID: 21421934

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