Saturday, March 28, 2009

One pill makes you larger and one pill makes you small



And the ones that mother gives you
Don't do anything at all
Go ask Alice
When she's ten feet tall

White Rabbit
---Jefferson Airplane

No, we're not really discussing hallucinogenic drugs today (despite the psychedelic reference). The real question for today is this: Does the wakefulness drug modafinil (Provigil) lessen the weight gain caused by atypical antipsychotics? Not really (Roerig et al., 2009), despite what the Elsevier press release tells us:
Combating Weight Gain Caused by Antipsychotic Treatments

Philadelphia, PA, March 26, 2009 – Antipsychotic drugs, such as olanzapine (Zyprexa), risperidone (Risperdal), and quetiapine (Seroquel) are commonly used to treat psychotic disorders like schizophrenia, but also bipolar disorder and even behavioral problems related to dementia. Unfortunately, the weight gain commonly experienced with antipsychotic treatment is an important side effect for many patients, and causes many patients to discontinue their use leading to even further problems. Biological Psychiatry, in its April 1st issue, is now publishing a new study that has evaluated an add-on treatment to potentially reduce treatment-associated weight gain.

In a randomized, double-blind, placebo-controlled trial, Dr. James Roerig and colleagues evaluated the effect of modafinil on olanzapine-associated weight gain in normal volunteer subjects. Modafinil is a drug currently used to increase wakefulness in individuals with sleep disorders, such as narcolepsy. All of the subjects received olanzapine, and half also received modafinil treatment while the other half instead received placebo. After three weeks, although the body mass index was increased in both groups, those receiving olanzapine/placebo showed significantly greater weight increase than those receiving olanzapine/modafinil.
The April 1st issue, hmm... You'll notice the study was conducted in normal volunteer participants and only for a 3 week period. What you didn't see in the press release is that during the 3 week period, 10 of the 50 original subjects withdrew from the trial (2 in modafinil + olanzapine group, and 8 in placebo + olanzapine group).

Zyprexa has rightfully received some bad press lately (so has Seroquel, but that story is more colorful). Although olanzapine is quite effective in treating schizophrenia and bipolar mania, it is notorious for causing very large weight gains in those taking it ("you'll gain five pounds just by filling the prescription" or 1.5 pounds per month according to a recent meta-analysis by Parsons et al., 2009). A 1999 article by Allison et al. was even worse: a gain of nearly a pound per week for 10 weeks (4.45 kg total!).1 One mechanism for this might involve increases in ghrelin, a hormone that stimulates appetite (see Brain Health Hacks).

Enter modafinil, which has been touted as a cognitive enhancing drug taken by some shifty academics. A recent paper on the Effects of Modafinil on Dopamine and Dopamine Transporters in the Male Human Brain (Volkow et al., 2009) caused some to ask whether modafinil might be addictive. But the answer is that it's probably not, even though it increases the level of dopamine (the "reward" neurotransmitter) by blocking the dopamine transporter. In addition to its effects on dopamine, modafinil also affects the norepinephrine neurotransmitter system, as shown in a technically difficult neuroimaging study (Minzenberg et al., 2008) of the human locus coeruleus, a small nucleus in the brainstem. Also on the plus side for modafinil is its potential usefulness in psychiatric practice: for improving attention and executive control function in schizophrenia (Morein-Zamir et al., 2007), and as an add-on medication in treating bipolar depression (Belmaker, 2007).

But the paper of today (Roerig et al., 2009) did none of that, instead enrolling healthy control participants2 and seeing whether modafinil attenuated the olanzapine-induced weight gain. A previous experiment by this group (Roerig et al., 2005) observed a 5 lb. increase over a 2 week period, significantly greater than both risperadone and placebo (Table 2). The number of calories consumed was numerically greater, but did not reach significance.


Table 2 (Roerig et al., 2005). Weight Change (in kilograms). Calorie Change (in kilocalories).

What about the current study?
In the completer analysis, the primary outcome variable, BMI [body mass index] change from baseline, was significantly different between groups with the olanzapine/placebo group experiencing a greater increase in BMI than the olanzapine/modafinil group (.89 + .59 vs. .47 + .50 kg/m2, p<.05). The mean weight gain in the placebo group was approximately twice that seen in the modafinil group (2.67 + 1.79 vs. 1.33 + 1.41 kg) over the 3-week exposure, and this approached significance.
HOWEVER, when controlled for gender [there were 8 men in the placebo group and zero in the modafinil group - nice!], the BMI difference was significant for week 1 but not for weeks 2 and 3. Over the short term of this study, there were no major differences in calories consumed, glucose and lipid levels, sleep, food cravings, or hunger and satiety ratings (with the exception of a slight increase in morning hunger for the placebo group). Ultimately, the authors concluded that...
The results of this trial should not be extrapolated to clinical practice at this time. These data do serve to support further evaluation in a patient population to determine if the weight modifying effect of modafinil can be demonstrated over a longer period of time.
Obviously, the people who receive prescriptions for this class of medications will be taking them for longer than 3 weeks, and the detrimental metabolic effects accumulate over months and years. Anything that can counteract the increased risks of significant weight gain, diabetes, hyperglycemia, and metabolic syndrome will be helpful in preserving the health of those who take atypical antipsychotics.

Footnote

1 I happened to notice that both of those studies had strong ties to Pfizer... coincidentally [or not], Pfizer touts its own atypical drug (Geodon) as not causing weight gain.

2 Who wants to take olanzapine for fun and profit? Anyone? In addition to getting fat, "You'll sleep 10-16 hours a day. You won't care about anything."

References

Allison DB, Mentore JL, Heo M, Chandler LP, Cappelleri JC, Infante MC, Weiden PJ. (1999). Antipsychotic-induced weight gain: a comprehensive research synthesis. Am J Psychiatry 156:1686-96.

Belmaker RH. (2007). Modafinil add-on in the treatment of bipolar depression. Am J Psychiatry 164:1143-5.

Minzenberg MJ, Watrous AJ, Yoon JH, Ursu S, Carter CS. (2008). Modafinil shifts human locus coeruleus to low-tonic, high-phasic activity during functional MRI. Science 322:1700-2.

Morein-Zamir S, Turner DC, Sahakian BJ. (2007). A review of the effects of modafinil on cognition in schizophrenia. Schizophr Bull. 33:1298-306.

Parsons B, Allison DB, Loebel A, Williams K, Giller E, Romano S, Siu C. (2009). Weight effects associated with antipsychotics: A comprehensive database analysis. Schizophr Res. Mar 23. [Epub ahead of print].

Roerig JL, Mitchell JE, de Zwaan M, Crosby RD, Gosnell BA, Steffen KJ, Wonderlich SA. (2005). A comparison of the effects of olanzapine and risperidone versus placebo on eating behaviors. J Clin Psychopharmacol. 25(5):413-8.

ResearchBlogging.org

Roerig, J., Steffen, K., Mitchell, J., Crosby, R., & Gosnell, B. (2009). An Exploration of the Effect of Modafinil on Olanzapine Associated Weight Gain in Normal Human Subjects Biological Psychiatry, 65 (7), 607-613 DOI: 10.1016/j.biopsych.2008.10.037

Volkow ND, Fowler JS, Logan J, Alexoff D, Zhu W, Telang F, Wang GJ, Jayne M, Hooker JM, Wong C, Hubbard B, Carter P, Warner D, King P, Shea C, Xu Y, Muench L, Apelskog-Torres K. (2009). Effects of modafinil on dopamine and dopamine transporters in the male human brain: clinical implications. JAMA 301:1148-54.

Note: The sound begins after 8 sec, and then... FEED YOUR HEAD!

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Thursday, March 19, 2009

Lie To Me on the Autobiographical Implicit Association Test


Lie to Me - Season 1 - "Moral Waiver" - Monica Raymund as Ria Torres
courtesy Adam Taylor/Fox

Lie detection is all the rage with the new TV show based on Paul Ekman's work1 that uses "microexpressions" to detect deception.

The use of brain imaging technologies as lie detectors, and the admissibility of data obtained in this fashion as evidence in a court of law, has a high media profile as well - most recently (and notoriously) because of a juvenile-sex-abuse case in San Diego, recounted by Wired Science. The Stanford Center for Law & the Biosciences Blog has sounded the alarm in their post, No Lie MRI being offered as evidence in court:
The case is a child protection hearing being conducted in the juvenile court. In brief, and because the details of the case are sealed and of a sensitive nature, the issue is whether a minor has suffered sexual abuse at the hands of a custodial parent and should remain removed from the home. The parent has contracted No Lie MRI and apparently undergone a brain scan...

The defense plans to claim the fMRI-based lie detection (or “truth verification”) technology is accurate and generally accepted within the relevant scientific community in part by narrowly defining the relevant community as only those who research and develop fMRI-based lie detection.
The Neurocritic weighed in on the overblown nature of these claims three years ago, with Brain Scans and Lie Detection: True or False?, Would I Lie to You?, and More Lies... Damn Lies... But even better, check out the excellent Deception Blog for an updated overview of the field.

UPDATE: Request to admit No Lie MRI report in California case is withdrawn. The dependent’s counsel in the case sent a thank you note to Professor Hank Greely, Director of the Center for Law and the Biosciences at Stanford, who also notes:
Special mention should go to Marcus Raichle, M.D., of Washington University in St. Louis [and recent winner of the George A. Miller Prize in Cognitive Neuroscience], for agreeing to take time out of his very busy schedule to fly to San Diego and testify that use of fMRI for lie detection is not yet generally accepted by the relevant scientific community as reliable, especially for real world, high-stakes situations involving individuals...
Given the high cost and dubious accuracy of fMRI technologies -- as well as the questionable accuracy of older EEG and polygraph methods -- there has been some interest in developing faster, easier, more reliable lie detection methods. Ian Sample at the Guardian's Science Blog went with this futuristic headline about the potential use of pupillometry as a routine security screening measure:
Homeland Security seeks Bladerunner-style lie detector

Do our eyes betray us when we lie? The US government hopes to find out

. . .

Under the Small Business Innovation Research programme, the department has asked tech companies to bid for contracts to kick-start research in the area. Such a system, if it works, would undoubtedly be useful at airports and other high-security points.
Here's the original SBIR solicitation for applications, which were due in February 2008:
TITLE: Assess Ability to use Eye Tracking and Pupil Dilation to Determine Intent to Deceive

DESCRIPTION: Recent government sponsored research is working to produce a new line of flexible physiological and behavioral sensor technologies that are to be available for homeland security applications. These sensors, which must be non-invasive in nature and protect the privacy of the individual(s) involved, will be used to support human centered/behavioral screening processes in a variety of high and low volume venues. Security screening is conducted to evaluate the risk of individuals entering transportation and other critical infrastructure and requires efficient, rapid and accurate examination of a person. Persons involved in or planning to be involved in possible malicious or deceitful acts will show various behavioral or physiological abnormalities. Much of the technology and publications to date have focused on detection of guilty individuals using electrodermal measures. Research into other psychophysiological measures or the mechanisms underlying deception is still in its early stages. Early research has shown that pupil size varies with changes in a person's cognitive processing load. Current but unproven studies suggest that a cognitive decision to deceive or practice deception will result in a increased pupil size due to the greater cognitive processing required in comparison to truthful recall. An assessment study to determine the correlation between Pupillometry (dilation and contraction of the pupil relative to observed stimulus or emotion) and intent to deceive is required.
For the ultimate in low-cost methods for lie detection, computerized reaction time tasks take the cake. An article about one of these appeared last year in Psychological Science (Sartori et al., 2008). The task they used is a variant of the Implicit Association Test (IAT) franchise that pits competing response tendencies against each other. Without getting into a lengthy discussion of the IAT, and the debates between its proponents and detractors,2 the autobiographical IAT (aIAT) employed by Sartori et al. ...
...allows one to evaluate which of two contrasting autobiographical events is true for a given individual. This is accomplished by requiring the respondent to complete two critical blocks of categorization trials, each of which pairs a different potentially autobiographical event with true events. Because pairing of a truly autobiographical event with true events should facilitate responses, the specific pattern of response times (RTs) in the two blocks indicates which autobiographical event is true and which is false.
The participants saw different types of sentences and had to classify them as true/false or guilty/innocent. Examples of the different stimuli are listed below.


adapted from Table 2 (Sartori et al., 2008).

The real trick was in the way these sentence types were matched to response keys. In a series of five blocks of trials, the subjects were told to respond to each sentence as rapidly as possible. Across five experiments (each of which had a different kind of "guilty knowledge"), the order was Block 1: logical discrimination (true/false) - Block 2: initial autobiographical information (guilty/innocent) - Block 3: initial double categorization (false/innocent and true/guilty) - Block 4: reversed autobiographical discrimination (false/true) - Block 5: reversed double categorization (true/innocent and false/guilty). The order of the critical blocks 3 and 5 was counterbalanced across participants (as was the order of 2 and 4, which counterbalanced the response mapping for autobiographical trials accordingly). The crucial measure was the comparison between RTs to the double categorization trials in Blocks 3 and 5 -- innocent participants were expected to be slower on the "conflict" trials in which true/guilty and false/innocent were matched to the same response key, while guilty participants (who always denied their crimes) were expected to show the opposite pattern, which would reveal they were lying about their innocence.

For the mock crime of stealing a CD for example, the results looked like this for the pairings of true/guilty and true/innocent:


Fig. 1C (Sartori et al., 2008). For Experiment 2, results are shown for the critical block associating true sentences with guilty sentences and for the critical block associating true sentences with innocent sentences.

Because the tests were able to discriminate between true and false events with 91% accuracy, the authors concluded that "the aIAT is an accurate method of detecting concealed knowledge that outperforms currently available lie-detection techniques." However, a brand new paper by Verschuere et al. (2009) has demonstrated that it's easy to fake your results in this aIAT! Oops. What Verschurere and colleagues did was provide the participants with instructions on how to beat the test. First they replicated the methods (and results) of Sartori et al. with naïve subjects on an initial aIAT. Before performing the aIAT a second time, however, the participants were told to slow down their responses in the true/guilty mapping condition. And the results for the faking version of the aIAT classified the majority of guilty liars as innocent. Imposing a response deadline, so the subjects had to respond within 1200 msec, did not alter the findings.

So there you have it. An extremely easy method for faking your results on the aIAT. In the past, The Neurocritic has taken the Human or Alien? test and the Dead or Alive? test. Turns out I'm neither human nor alien, and neither dead nor alive. Read those posts, and then try the tests yourselves.

Footnotes

1 However, as noted recently by World of Psychology, a paper by Bond (2008) questioned whether Ekman et al. (1991, 1999) omitted data unfavorable to their previously reported lie detection success rate of 73% in some federal agents.

2 The sadly defunct blog Mixing Memory was particularly critical of the IAT:
The IAT isn't the only test of implicit "attitudes." . . . However, the IAT is the most popular, and has received a great deal of attention in the popular press, due in large part to a public relations campaign by its authors and the NSF and NIMH. In my mind, giving the IAT so much publicity is the most irresponsible thing I've seen in psychology since I began studying it... While the IAT has been publicized (by its authors!) as a measure of implicit attitudes, and even more, as a measure of implicit prejudice, there is no real evidence that it measures attitudes, much less prejudices. In fact, it's not at all clear what it measures, though the fact that its psychometric properties are pretty well defined at least implies that it measures something. On top of that, the IAT (like all of the other implicit tests) has serious methodological flaws that are currently being discussed in the literature. It's just irresponsible to publicize work, and claim that it does something very particular, when the work is still in the early stages and it's not at all clear what it's actually doing (read paper, or this one, for discussions of some of the problems with the IAT and other measures, including whether they actually measure "attitudes").
References

Sartori, G., Agosta, S., Zogmaister, C., Ferrara, S.D., & Castiello, U. (2008). How to accurately assess autobiographical events. Psychological Science 19:772–780.

ResearchBlogging.org

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


Lie to Me - Season 1 - "Moral Waiver" - Kelli Williams as Gillian Foster and Tim Roth as Cal Lightman
courtesy Adam Taylor/Fox

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Saturday, March 14, 2009

I Know What You Sweated Last Summer


From the authors who first brought you "sexual sweat" (Zhou & Chen, 2008)...

Be afraid... be very afraid and prepare yourself for the sequel: "FEARFUL SWEAT" (Zhou & Chen, 2009)!!!

In case you didn't know that "sexual sweat" (collected from men watching porn) differs from ordinary sweat, the results of an fMRI experiment suggested that the orbitofrontal cortex and the fusiform region in 20 female participants responded differently when smelling the two substances (Zhou & Chen, 2008). However, we don't know anything specific about the unique chemical composition of sweat obtained from sexually aroused men, and why it resulted in differential brain activity in women who could not identify the odor as "sweaty/human" (see When I Get That Feeling, I Need Sexual Sweating).



Nonetheless, in the present study Zhou and Chen (2009) wanted to determine the effects of another putative chemosensory signal on the perception of emotional expressions in faces. Specifically, as they explain below...
...we conducted two experiments focused on the effect of a fear-related chemosignal (sweat collected from donors viewing horror videos) in an emotion-identification task. We used the same type of olfactory stimuli (emotional sweat collected on gauze pads and gauze pads with no sweat) throughout, but varied the effectiveness of the visual input by varying the ambiguity of the facial emotions (from somewhat happy to ambiguous to somewhat fearful). Our manipulation of ambiguity was achieved through morphing between happy and fearful faces [as shown in Fig. 1a].

Fig. 1a (Zhou & Chen, 2009). Examples of the morphed faces of two actors. For each actor, we selected seven morphs, ranging from somewhat happy to somewhat fearful. These faces were judged to be fearful 20% to 80% of the time in our pilot experiment, in the absence of any olfactory stimuli. Specifically, the Level 4 morph for each actor was the most ambiguous, judged to be fearful in the pilot study 45% to 55% of the time.

And what about the olfactory stimuli obtained from the male sweat donors?
On the day of each session, they wore next to their skin a new T-shirt (provided by the experimenter), to prevent odor contamination by their regular clothes. During each session, they kept a 4- x 4-in. pad (rayon-polyester blend for maximum absorbance) under each armpit while they watched each of three 20-min video segments intended to produce the emotions of fear (horror movies), happiness (slapstick comedies), and neutrality, respectively. Different videos were shown in each session. During the videos, participants’ heart rate was recorded... After watching each video, the donors rated how angry, fearful, happy, neutral, and sad they felt during the video, using a 100-mm visual analog scale. From each donor, we selected the pads worn during the 20-min videos that elicited the highest level of self-reported happy feelings and the highest level of self-reported fearful feelings.
So the 48 young female subjects (mean age 19.6 years) viewed the various faces while exposed to different olfactory stimuli, and decided whether they were happy or fearful. Results indicated that on average they were significantly more likely to identify the most ambiguous morph as fearful when smelling the fearful sweat relative to the control condition (which, unfortunately, was a rayon-polyester pad with no sweat). Although the likelihood of identifying an ambiguous face as fearful did not differ between the happy sweat and control conditions, there was no direct statistical comparison between the two sweat conditions, which would seem to be a problem.


adapted from Fig. 2b (Zhou & Chen, 2009).

Nevertheless, there was some evidence that male horror movie sweat was able to bias the women towards viewing an ambiguous face as fearful, and this was not due to the pleasantness (or lack thereof) or intensity of the olfactory stimulus. I'd be curious to see how the "sweat of neutrality" and the "sweat of sexual arousal" [as identified by Zhou & Chen, 2008) in their earlier study] would influence emotion recognition judgments...


References

Zhou W, Chen D. (2008). Encoding Human Sexual Chemosensory Cues in the Orbitofrontal and Fusiform Cortices. Journal of Neuroscience, 28 (53), 14416-14421.

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

Integrating emotional cues from different senses is critical for adaptive behavior. Much of the evidence on cross-modal perception of emotions has come from studies of vision and audition. This research has shown that an emotion signaled by one sense modulates how the same emotion is perceived in another sense, especially when the input to the latter sense is ambiguous. We tested whether olfaction causes similar sensory modulation of emotion perception. In two experiments, the chemosignal of fearful sweat biased women toward interpreting ambiguous expressions as more fearful, but had no effect when the facial emotion was more discernible. Our findings provide direct behavioral evidence that social chemosignals can communicate emotions and demonstrate that fear-related chemosignals modulate humans’ visual emotion perception in an emotion-specific way—an effect that has been hitherto unsuspected.

Bonus! See sensory psychologist and olfactory specialist Avery Gilbert's take on these two studies in Basic Instinct: The Smell of Fear and Sex.



TAG body spray for sick cats. "This spray is definitely not for me."

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Thursday, March 05, 2009

Atheists Are Neurotic and Religious Zealots Are Antisocial

"Religion is the Xanax of the people" (Inzlicht et al., 2009).


The clever quote above is from the latest paper to garner the _______ Are Neurotic and _______ Are Antisocial style of sensationalistic headline, a study that claims to reveal the Neural Markers of Religious Conviction. I was all prepared to hate the paper, but the authors are not unreasonable in their hypotheses and predictions.

But first, a little background. A year and a half ago, Amodio et al. (2007) published an eye-catching article in Nature Neuroscience that reported on supposed "hard-wired" differences in the brains of liberals and conservatives. The typical media feeding frenzy ensued, complete with simplistic headlines (and some interpretive stretching on the part of the authors).

As we recounted in The Error of Prognosticating Political View by Brain Wave,1 there were:
...overblown quotes:
Are We Predisposed to Political Beliefs?

. . .

"In the past, people thought that…[political leanings were]…all environmentally influenced, a combination of biological dispositions as well as cultural shaping," says David Amodio, an assistant professor of psychology at New York University. However, a new study, led by Amodio, indicates that political bent "is not just a choice people have, but it seems to be linked to fundamental differences in the way people process information."
And the baseless assertion of innate differences between the brains of liberals and conservatives:
brain neurons of liberals and conservatives fire differently [sic] when confronted with tough choices, suggesting that some political divides may be hard-wired, according a study released Sunday.
That study is quite relevant here because Inzlicht and colleagues used the same neural measure as Amodio et al. (2007). Both experiments used EEG recordings, specifically event-related potentials. The ERP brain waves reflect electrophysiological activity recorded remotely from the scalp. While it's great for determining the temporal parameters of neural activity, it's not so great at determining where the activity is located in the brain.

The brain wave of interest is the error-related negativity (ERN), recorded at the time that people make mistakes in a task:
The ERN is evident as a large negative polarity peak in the event-related brain potential waveform that occurs when people make errors in reaction time tasks. It begins at the moment of the error and reaches a maximum about 100 milliseconds later (see Gehring et al., 1993, PDF). It is largest at fronto-central scalp locations and appears to come from an area of the brain called the anterior cingulate cortex...
There is some disagreement about what the ERN wave represents: a direct response to the mismatch between the intended action and the actual one, a more generic response to conflict in general, or an emotional response to f***ing up. And because EEG is recorded from the scalp, one cannot say for certain that the anterior cingulate is the sole origin.

What does all this have to do with that old time religion? Inzlicht et al. review the neuropsychology of anxiety and how religion serves to quell the angst:
XANAX OF THE PEOPLE

One of religion’s primary functions may be to help people cope with existential uncertainty. In the words of St. Ambrose (ca. 390 AD), ‘‘amid the agitations of the world, the Church remains unmoved; the waves cannot shake her. While around her everything is in a horrible chaos, she offers to all the shipwrecked a tranquil port where they will find safety’’ (quoted in Durant, 1950, p. 79). Religion provides people with a meaning system that helps them navigate through and understand an infinitely complex and uncertain world (Peterson, 1999). It meets the fundamental need to comprehend the deepest problems of existence. Scholars of religion, from James (1902/2002) to Durkheim (1912/1954), have noted that religion imbues life with motivation, purpose, and meaning.
What does anxiety have to do with the ERN wave?? It's larger in those with anxiety disorders, as Hajcak et al. (2004) have noted. And the hypothesis of the present paper?
How is it that religion can bring about both peace of mind and zealous conviction? We suggest that religious conviction buffers against anxiety by providing relief from the experience of uncertainty and error, and in so doing, strengthening convictions and narrowing attention away from inconsistencies. We hypothesize that this muted response to uncertainty and error is evident neurophysiologically such that religious conviction is associated with reduced activity in the anterior cingulate cortex (ACC), a cortical system involved in a form of attention that serves to regulate both cognitive and emotional processing...
Although it's simplistic of them to say the ERN reflects only ACC activity, they did avoid some of the pitfalls of Amodio et al.'s paper by taking into account personality factors that can influence this brain wave (hence, the "neurotic" and "antisocial" title).
We measured the amplitude of each participant’s ERN during the Stroop task and correlated these values with participants’ self-reported religious zeal (Study 1) and self-reported belief in God (Study 2). In both studies, we also measured other psychological variables to control for their impact on the hypothesized correlation between religious conviction and ACC activity. We expected greater religious conviction to predict lower ERN amplitudes in both studies, even after controlling for important personality traits and cognitive capacities.
And that's what they found.


Fig. 1C (Inzlicht et al., 2009). The relation between religious zeal and anterior cingulate cortex activity: event-related potentials (ERPs) at electrode Cz for error-related negativities (ERNs) for people high and low in religious zeal.

The Religious Zeal scale was used to assess ardent religious conviction. Items included ‘‘I aspire to live and act according to my religious beliefs,’’ ‘‘My religious beliefs are grounded in objective truth,’’ and ‘‘I would support a war that defended my religious beliefs.’’ Behavioral inhibition, behavioral activation, self-esteem, and the need for cognitive closure were also assessed.

However, they repeat some of the drawbacks from Amodio's paper by reporting correlations but only showing a median split (presumably) in the figure (and we don't know if this group difference is significant). We also don't know anything about the reaction times, other than the odd finding that greater religious zealotry was associated with a larger Stroop interference effect (slower for BLUE than for RED) but fewer errors.

In Experiment 2 with a different group of subjects, the self-report measures were belief in God, political conservatism à la Amodio, and the Big Five personality inventory. Here, too, they found that greater religious belief correlated with smaller ERN responses to errors (and personality did not account for this).

Unexplained loose ends? I see at least two of them. First, the estimated localization of the ERN response within the ACC was centimeters apart in the two groups of subjects. Granted, estimated source localization for ERP is tenuous at best (especially with only 32 electrodes), but these two spots are in different functional regions of the ACC.


Fig 1D (top) and Fig 2D (bottom) - illustration of the generator for the ERN (in anterior cingulate cortex), as determined by source localization.

More critically, this experiment failed to replicate Amodio's finding: there was absolutely no correlation between self-assessed conservatism and the ERN wave! [as in this figure] I don't have a high need for cognitive closure, but it appears to be a glaring omission that this was not even mentioned in the paper. I'm feeling a very large error-related negativity at the moment. Maybe I need a Xanax. Or a religious experience...

Footnote

1 For more on the same study, see Liberals Are Neurotic and Conservatives Are Antisocial, as well as David Amodio Responds to his neurocritics.

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. 10:1246-1247.

Hajcak G, McDonald N, Simons RF. (2004). Error-related psychophysiology and negative affect. Brain Cogn. 56:189-97.

ResearchBlogging.org

Michael Inzlicht, Ian McGregor, Jacob B. Hirsh, Kyle Nash (2009). Neural Markers of Religious Conviction Psychological Science DOI: 10.1111/j.1467-9280.2009.02305.x

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Wednesday, March 04, 2009

Brain Injury Awareness Month



From the BIAA website:

Brain Injury Awareness Month 2009

Did you know March is Brain Injury Awareness Month? It is and each March the Brain Injury Association of America (BIAA) and the BIA chartered state affiliates throughout the United States partner together with other organizations, businesses, schools, survivors and their families and others to generate awareness and understanding of brain injury. This year’s focus is dedicated to Sports & Concussions, specifically youth sports.

According to the Centers for Disease Control and Prevention (CDC) an estimated 1.6-3.8 million sports and recreation related concussions occur in the U.S. each year. Concussions occur even if an athlete doesn’t lose consciousness and in fact, is the most common type of brain injury sustained in sports.

A concussion is a type of traumatic brain injury (TBI) caused by a blow or jolt to the head. The severity of an injury can range from mild to severe. Signs and symptoms may be noticeable immediately, or it may take days or weeks before they are present.

This PDF from brainline.org lists the March events in the U.S. and provides a link to the International Brain Awareness Week (BAW) Campaign (March 16-22) organized by the Dana Alliance for Brain Initiatives.

Of course, the Society for Neuroscience is another excellent source of information on BAW. And who can resist a bowl of 50 brain erasers?


From Neuro-Mart.

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Tuesday, March 03, 2009

Fame, Success, and Money for Maniacs


Flavio Briatore

The headline below is not offensive or anything, now is it?
Maniacs often aspire for fame, success and money: study

By Jyoti Pal

London, March 2: Mania and depression sufferers are more likely to set higher goals in life. Success, money and fame, is what attracts them, a new research has found.

Mania is already linked to a belief in the importance of achievement, creativity and artistic talent. But does it drive people into setting higher goals for the future? Researchers tried to find out.
Ugh, that's awful...

The original headline1 (or at least, the more widely circulated one) for the same story is:
Study links mania to desire for success

March 2, 2009, 11:59 am

People with manic or bipolar tendencies have higher expectations of what they can achieve in terms of success, money and fame, a new study published on Monday finds.

Researchers assessed 103 people, including 27 with diagnosed manic depression, or bipolar disorder, a brain disorder that causes unusual and often dramatic shifts in a person's mood, energy and ability to function.

They were asked to fill in questionnaires designed to assess their most ambitious life goals, rating the likelihood of certain things happening to them, such as appearing regularly on TV or earning $US20 million ($A31.42 million) or more.

"We found that the people who had experienced episodes of mania during their lives had the highest expectations of achieving popular success and financial success," said Professor Sheri L. Johnson from the University of California.
The paper (Johnson et al., in press) will appear in the British Journal of Clinical Psychology. I can't say much more about it (because I don't have access), but the abstract is reprinted below.

Somehow the Telegraph took the same press release and spun it in the opposite direction...
Depression linked to desire for fame, say scientists

People who suffer from depression and mania are more likely to focus on success, money and fame than others, research has found

By Ben Leach
Last Updated: 7:05PM GMT 01 Mar 2009

The study, published in the British Journal of Clinical Psychology, found that mania and depression may drive people to set higher goals.

Dr Johnson, one of the researchers from the University of California, Berkeley who conducted the study, said: "Manic episodes are characterised by elevated mood as well as increased talkativeness, racing thoughts, decreased need for sleep and extreme distractibility.

"Mania has already been linked to a belief in the importance of achievement and so we wanted to discover whether it is also linked with higher expectations for the future."
Anyone reading the story can plainly see the headline is completely wrong!

Here we have two egregious cases of bad neurojournalism with minimal editorial oversight from the respective publications.

For another (completely unrelated) example of bad science journalism, read the plight of Dr Petra Boynton as she valiantly tried to inform the press about the errors in a New York Times article on sex research: What do women want? Not this!

Managing Director of Renault F1 Flavio Briatore and Elisabetta Gregoraci attend the 'Babel' premiere at the Palais des Festivals during the 59th International Cannes Film Festival May 23, 2006 in Cannes, France.
(Photo by Pascal Le Segretain/Getty Images Entertainment)

Footnote

1 Thanks to Sandy Gautam of The Mouse Trap for the original link.

Reference

Johnson SL, Eisner LR, Carver CS (in press). Elevated expectancies among persons diagnosed with bipolar disorder. British Journal of Clinical Psychology.

Objective Students at risk for bipolar disorder endorse highly ambitious goals. This study examined expectations for the future among people with actual bipolar disorder, versus people with no history of mood disorder and persons with history of unipolar depression. Methods One hundred and three students were assessed for Axis I disorders and completed a measure of expected life outcomes. Results History of mania, but not history of depression, related to higher expectations of achieving popular fame and wealth. Conclusions People with history of mania anticipate great success in domains involving public recognition.

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