Second movement of the sonata started in Monday's post. David Goldberger playing treble, I'm playing base.
Wednesday, March 31, 2010
Second movement of the sonata started in Monday's post. David Goldberger playing treble, I'm playing base.
Yet another interesting bit of work involving Ray Dolan and his collaborators. Here is the abstract and a summary figure:
Humans often accept the status quo when faced with conflicting choice alternatives. However, it is unknown how neural pathways connecting cognition with action modulate this status quo acceptance. Here we developed a visual detection task in which subjects tended to favor the default when making difficult, but not easy, decisions. This bias was suboptimal in that more errors were made when the default was accepted. A selective increase in subthalamic nucleus (STN) activity was found when the status quo was rejected in the face of heightened decision difficulty. Analysis of effective connectivity showed that inferior frontal cortex (rIFC), a region more active for difficult decisions, exerted an enhanced modulatory influence on the STN during switches away from the status quo. These data suggest that the neural circuits required to initiate controlled, nondefault actions are similar to those previously shown to mediate outright response suppression. We conclude that specific prefrontal-basal ganglia dynamics are involved in rejecting the default, a mechanism that may be important in a range of difficult choice scenarios.
Effects of decision difficulty and default rejection on connectivity. (A) Coronal sections are shown. Circled are the regions that were entered into a connectivity analysis. (B) Schematic showing the winning dynamic causal model and the pattern of significant connections. Default rejection (reject) was associated with increased influence of the rIFC on the STN. The authors observed correlation of activity in bilateral inferior frontal cortex (IFC) and bilateral medial frontal cortex (MFC)with increasing reaction time for rejecting default behavior. They saw additional main effects of decision difficulty in both MFC and IFC, in line with specific recruitment of these regions during situations requiring increased cognitive control.
Tuesday, March 30, 2010
This TED talk by Sam Harris is worth watching. He makes the point that the fact-value distinction is far from clear.
An interesting point from Cima et al. (open access):
Adult psychopaths have deficits in emotional processing and inhibitory control, engage in morally inappropriate behavior, and generally fail to distinguish moral from conventional violations. These observations, together with a dominant tradition in the discipline which sees emotional processes as causally necessary for moral judgment, have led to the conclusion that psychopaths lack an understanding of moral rights and wrongs. We test an alternative explanation: psychopaths have normal understanding of right and wrong, but abnormal regulation of morally appropriate behavior. We presented psychopaths with moral dilemmas, contrasting their judgments with age- and sex-matched (i) healthy subjects and (ii) non-psychopathic, delinquents. Subjects in each group judged cases of personal harms (i.e. requiring physical contact) as less permissible than impersonal harms, even though both types of harms led to utilitarian gains. Importantly, however, psychopaths’ pattern of judgments on different dilemmas was the same as those of the other subjects. These results force a rejection of the strong hypothesis that emotional processes are causally necessary for judgments of moral dilemmas, suggesting instead that psychopaths understand the distinction between right and wrong, but do not care about such knowledge, or the consequences that ensue from their morally inappropriate behavior.
Monday, March 29, 2010
Monday, Wednesday, Friday this week I'm posting the three movements of the Mozart Sonata for 4-hands, K. 358. which I played in concert with David Goldberger in Fort Lauderdale on March 7. Today is the Allegro.
Humans have a unique ability to coordinate their motor movements to an external auditory stimulus, as in music-induced foot tapping or dancing. This behavior currently engages the attention of scholars across a number of disciplines. However, very little is known about its earliest manifestations. The aim of the current research was to examine whether preverbal infants engage in rhythmic behavior to music. To this end, we carried out two experiments in which we tested 120 infants (aged 5–24 months). Infants were exposed to various excerpts of musical and rhythmic stimuli, including isochronous drumbeats. Control stimuli consisted of adult- and infant-directed speech. Infants’ rhythmic movements were assessed by multiple methods involving manual coding from video excerpts and innovative 3D motion-capture technology. The results show that (i) infants engage in significantly more rhythmic movement to music and other rhythmically regular sounds than to speech; (ii) infants exhibit tempo flexibility to some extent (e.g., faster auditory tempo is associated with faster movement tempo); and (iii) the degree of rhythmic coordination with music is positively related to displays of positive affect. The findings are suggestive of a predisposition for rhythmic movement in response to music and other metrically regular sounds.
Friday, March 26, 2010
Following Monday's and Wednesday's postings, the final portion of the Schubert Fantasy. I'm playing treble, David Goldberger is playing base.
John Tierney describes cross cultural studies of sharing and fairness (comparing, for example, hunter-gatherers with midwestern Wal-Mart shoppers) that found:
...the strongest predictor of fairness was the community’s level of “market integration,” - measured by the percentage of the diet that was purchased. The people who got all or most of their food by hunting, fishing, foraging or growing it themselves were less inclined to share a prize equally....Markets don’t work very efficiently if everyone acts selfishly and believes everyone else will do the same...You end up with high transaction costs because you have to have all these protections to cover every loophole. But if you develop norms to be fair and trusting with people beyond your social sphere, that provides enormous economic advantages and allows a society to grow.The work he is summarizing is by Henrich et al. Their abstract:
Large-scale societies in which strangers regularly engage in mutually beneficial transactions are puzzling. The evolutionary mechanisms associated with kinship and reciprocity, which underpin much of primate sociality, do not readily extend to large unrelated groups. Theory suggests that the evolution of such societies may have required norms and institutions that sustain fairness in ephemeral exchanges. If that is true, then engagement in larger-scale institutions, such as markets and world religions, should be associated with greater fairness, and larger communities should punish unfairness more. Using three behavioral experiments administered across 15 diverse populations, we show that market integration (measured as the percentage of purchased calories) positively covaries with fairness while community size positively covaries with punishment. Participation in a world religion is associated with fairness, although not across all measures. These results suggest that modern prosociality is not solely the product of an innate psychology, but also reflects norms and institutions that have emerged over the course of human history.
Elizabeth Kolbert writes a very accessible article (PDF here) having the title of this post in the March 22 issue of The New Yorker. The topic is happiness, how to measure it, and why we are so bad at knowing what will actually make us happy (the paradox of "the happy peasant and the miserable millionaire"). It covers the same territory as the Daniel Gilbert book "Stumbling on Happiness" that I abstracted in MindBlog several years ago (enter Gilbert in the search box in the left column to find those posts).
Thursday, March 25, 2010
Figure - A hypothetical cascade. This diagram illustrates the difference between the spread of the interpersonal effects across individuals and the persistence of effects across time. We abstract from the numerous interactions that take place between individuals in these experiments to focus on a specific, illustrative set of pathways. Cooperative behavior spreads three degrees of separation: if Eleni increases her contribution to the public good, it benefits Lucas (one degree), who gives more when paired with Erika (two degrees) in period 2, who gives more when paired with Jay (three degrees) in period 3, who gives more when paired with Brecken in period 4. The effects also persist over time, so that Lucas gives more when paired with Erika (period 2) and also when paired with Lysander (period 3), Bemy (period 4), Sebastian (period 5), and Nicholas (period 6). There is also persistence at two degrees of separation, because Erika givesmore not only when paired with Jay (period 3) but also when paired with Harla (period 4) and James (period 5). All the paths in this illustrative cascade are supported by significant results in the experiments, and it is important to note that if Eleni decreases her initial contribution, her uncooperative behavior can spread and persist as well.
A reader of Monday's post asked if I could post abstracts from the special issue (on Mindfulness meditation) of the journal Emotion mentioned in that post. I thought the abstracts were open access, but apparently they are not. Here I pass on a PDF of the introductory article by Williams that summarizes the contributions (Mindfulness and psychological process. Williams, J. Mark G.; Emotion, Vol 10(1), Feb, 2010. pp. 1-7.)
Below I show the table of contents and a few abstracts from the issue (email me if you have further requests).
Empirical explorations of mindfulness: Conceptual and methodological conundrums. Davidson, Richard J.; Emotion, Vol 10(1), Feb, 2010. pp. 8-11.
[Research on mindfulness is entering a new era and coming into the mainstream. The group of articles in this Special Issue exemplifies research on the impact of mindfulness on, or the relation between mindfulness and, different components of emotion processing and emotion regulation. Affective processes are a key target of contemplative interventions. The long-term consequences of most contemplative traditions include a transformation of trait affect. After all, if change was not enduring and did not impact everyday life, it would be of little utility. This brief commentary highlights several important conceptual and methodological issues that are central to research on mindfulness, particularly as it is applied to transforming emotion. The term “mindfulness” has been used to refer to an extraordinarily wide range of phenomena in this group of articles, ranging from mindfulness as a state, to mindfulness as a trait and finally mindfulness as an independent variable, that is, something this is manipulated in an experiment. It is imperative that we always qualify our use of this term by the methods we use to operationalize the construct. The measurement of mindfulness and the duration of its training, and the development of adequate comparison conditions against which to compare mindfulness training remain as important issues for further study. Moreover additional research attention on the potential targets within the emotion domain of contemplative practices is required. Great progress has been in this research area and we have much to look forward in the future.]
Dispositional mindfulness and depressive symptomatology: Correlations with limbic and self-referential neural activity during rest. Way, Baldwin M.; Creswell, J. David; Eisenberger, Naomi I.; Lieberman, Matthew D.; Emotion, Vol 10(1), Feb, 2010. pp. 12-24.
[ To better understand the relationship between mindfulness and depression, we studied normal young adults (n = 27) who completed measures of dispositional mindfulness and depressive symptomatology, which were then correlated with (a) rest: resting neural activity during passive viewing of a fixation cross, relative to a simple goal-directed task (shape-matching); and (b) reactivity: neural reactivity during viewing of negative emotional faces, relative to the same shape-matching task. Dispositional mindfulness was negatively correlated with resting activity in self-referential processing areas, whereas depressive symptomatology was positively correlated with resting activity in similar areas. In addition, dispositional mindfulness was negatively correlated with resting activity in the amygdala, bilaterally, whereas depressive symptomatology was positively correlated with activity in the right amygdala. Similarly, when viewing emotional faces, amygdala reactivity was positively correlated with depressive symptomatology and negatively correlated with dispositional mindfulness, an effect that was largely attributable to differences in resting activity. These findings indicate that mindfulness is associated with intrinsic neural activity and that changes in resting amygdala activity could be a potential mechanism by which mindfulness-based depression treatments elicit therapeutic improvement....dispositional mindfulness and depressive symptomatology show opposite relationships with resting activity in the right amygdala, indicating that this may be a potential mechanism linking mindfulness-based treatments with reductions in depressed mood and relapse risk. That resting state activity differences largely explained the differences in emotional reactivity underscores the importance of understanding intrinsic activity within the brain. Perhaps it is fitting that mindfulness, a practice focused on observant contemplation rather than action, is associated with neural activity when an individual is just “being” rather than “doing.”]
Minding one’s emotions: Mindfulness training alters the neural expression of sadness. Farb, Norman A. S.; Anderson, Adam K.; Mayberg, Helen; Bean, Jim; McKeon, Deborah; Segal, Zindel V.; Emotion, Vol 10(1), Feb, 2010. pp. 25-33.
[Recovery from emotional challenge and increased tolerance of negative affect are both hallmarks of mental health. Mindfulness training (MT) has been shown to facilitate these outcomes, yet little is known about its mechanisms of action. The present study employed functional MRI (fMRI) to compare neural reactivity to sadness provocation in participants completing 8 weeks of MT and waitlisted controls. Sadness resulted in widespread recruitment of regions associated with self-referential processes along the cortical midline. Despite equivalent self-reported sadness, MT participants demonstrated a distinct neural response, with greater right-lateralized recruitment, including visceral and somatosensory areas associated with body sensation. The greater somatic recruitment observed in the MT group during evoked sadness was associated with decreased depression scores. Restoring balance between affective and sensory neural networks—supporting conceptual and body based representations of emotion—could be one path through which mindfulness reduces vulnerability to dysphoric reactivity.]
Effects of mindfulness on meta-awareness and specificity of describing prodromal symptoms in suicidal depression. Hargus, Emily; Crane, Catherine; Barnhofer, Thorsten; Williams, J. Mark G.; Emotion, Vol 10(1), Feb, 2010. pp. 34-42.
Cortical thickness and pain sensitivity in zen meditators. Grant, Joshua A.; Courtemanche, Jérôme; Duerden, Emma G.; Duncan, Gary H.; Rainville, Pierre; Emotion, Vol 10(1), Feb, 2010. pp. 43-53.
Examining the protective effects of mindfulness training on working memory capacity and affective experience. Jha, Amishi P.; Stanley, Elizabeth A.; Kiyonaga, Anastasia; Wong, Ling; Gelfand, Lois; Emotion, Vol 10(1), Feb, 2010. pp. 54-64.
[...findings suggest that sufficient mindfulness training practice may protect against functional impairments associated with high-stress contexts. ]
Differential effects on pain intensity and unpleasantness of two meditation practices. Perlman, David M.; Salomons, Tim V.; Davidson, Richard J.; Lutz, Antoine; Emotion, Vol 10(1), Feb, 2010. pp. 65-71.
A preliminary investigation of the effects of experimentally induced mindfulness on emotional responding to film clips. Erisman, Shannon M.; Roemer, Lizabeth; Emotion, Vol 10(1), Feb, 2010. pp. 72-82.
Effects of mindfulness-based stress reduction (MBSR) on emotion regulation in social anxiety disorder. Goldin, Philippe R.; Gross, James J.; Emotion, Vol 10(1), Feb, 2010. pp. 83-91.
Expressive flexibility. Westphal, Maren; Seivert, Nicholas H.; Bonanno, George A.; Emotion, Vol 10(1), Feb, 2010. pp. 92-100.
Wednesday, March 24, 2010
Part 2 of the Schubert fantasy, part I was posted Monday. I'm playing the treble, David Goldberger is playing the base.
While we have strong evidence for genetic effects on basic sensory processes (such as inherited color vision defects) evidence for genetic control of specific higher cognitive processes - (as distinct, for example, from more multi-domain processes like general intelligence or 'g') - has been harder to obtain. Wilmer et al. (open access) now report twin studies that offer strong evidence that face recognition ability has a strong genetic component, and that experience or environment plays a surprisingly small role. People are not 'all face recognition experts,' and this variation has now been shown to have a largely genetic basis:
Compared with notable successes in the genetics of basic sensory transduction, progress on the genetics of higher level perception and cognition has been limited. We propose that investigating specific cognitive abilities with well-defined neural substrates, such as face recognition, may yield additional insights. In a twin study of face recognition, we found that the correlation of scores between monozygotic twins (0.70) was more than double the dizygotic twin correlation (0.29), evidence for a high genetic contribution to face recognition ability. Low correlations between face recognition scores and visual and verbal recognition scores indicate that both face recognition ability itself and its genetic basis are largely attributable to face-specific mechanisms. The present results therefore identify an unusual phenomenon: a highly specific cognitive ability that is highly heritable. Our results establish a clear genetic basis for face recognition, opening this intensively studied and socially advantageous cognitive trait to genetic investigation.
Readers who were interested in the recent post on statins should have a look at the comments that have come in. They note studies showing adverse effects of statins on cognition and memory.
Tuesday, March 23, 2010
Michiko Kakutani writes an excellent article in last Sunday's NYTimes. The article is so rich that you really must read the whole thing, but I will pass on a few clips here. The article starts with reference to David Shields new book "Reality Hunger" which consists of 618 fragments, including hundreds of quotations taken from other writers.
...fiction “has never seemed less central to the culture’s sense of itself.” ..“Who owns the music and the rest of our culture? We do — all of us — though not all of us know it yet. Reality cannot be copyrighted.”
...the dynamics of the Web, as the artist and computer scientist Jaron Lanier observes in another new book, are encouraging “authors, journalists, musicians and artists” to “treat the fruits of their intellects and imaginations as fragments to be given without pay to the hive mind.”...It’s also a question, as Mr. Lanier, 49, astutely points out in his new book, “You Are Not a Gadget,” of how online collectivism, social networking and popular software designs are changing the way people think and process information, a question of what becomes of originality and imagination in a world that prizes “metaness” and regards the mash-up as “more important than the sources who were mashed.”
Mr. Lanier’s book, which makes an impassioned case for “a digital humanism,” is only one of many recent volumes to take a hard but judicious look at some of the consequences of new technology and Web 2.0. Among them are several prescient books by Cass Sunstein, 55, which explore the effects of the Internet on public discourse; Farhad Manjoo’s “True Enough,” which examines how new technologies are promoting the cultural ascendancy of belief over fact; “The Cult of the Amateur,” by Andrew Keen, which argues that Web 2.0 is creating a “digital forest of mediocrity” and substituting ill-informed speculation for genuine expertise; and Nicholas Carr’s book “The Shallows” (coming in June), which suggests that increased Internet use is rewiring our brains, impairing our ability to think deeply and creatively even as it improves our ability to multitask.
More people are impatient to cut to the chase, and they’re increasingly willing to take the imperfect but immediately available product over a more thoughtfully analyzed, carefully created one. Instead of reading an entire news article, watching an entire television show or listening to an entire speech, growing numbers of people are happy to jump to the summary, the video clip, the sound bite — never mind if context and nuance are lost in the process; never mind if it’s our emotions, more than our sense of reason, that are engaged; never mind if statements haven’t been properly vetted and sourced.
Given the constant bombardment of trivia and data that we’re subjected to in today’s mediascape, it’s little wonder that noisy, Manichean arguments tend to get more attention than subtle, policy-heavy ones; that funny, snarky or willfully provocative assertions often gain more traction than earnest, measured ones; and that loud, entertaining or controversial personalities tend to get the most ink and airtime. This is why Sarah Palin’s every move and pronouncement is followed by television news, talk-show hosts and pundits of every political persuasion. This is why Glenn Beck and Rush Limbaugh on the right and Michael Moore on the left are repeatedly quoted by followers and opponents. This is why a gathering of 600 people for last month’s national Tea Party convention in Nashville received a disproportionate amount of coverage from both the mainstream news media and the blogosphere.
For his part Mr. Lanier says that because the Internet is a kind of “pseudoworld” without the qualities of a physical world, it encourages the Peter Pan fantasy of being an entitled child forever, without the responsibilities of adulthood. While this has the virtues of playfulness and optimism, he argues, it can also devolve into a “Lord of the Flies”-like nastiness, with lots of “bullying, voracious irritability and selfishness” — qualities enhanced, he says, by the anonymity, peer pressure and mob rule that thrive online.
As reading shifts “from the private page to the communal screen,” Mr. Carr writes in “The Shallows,” authors “will increasingly tailor their work to a milieu that the writer Caleb Crain describes as ‘groupiness,’ where people read mainly ‘for the sake of a feeling of belonging’ rather than for personal enlightenment or amusement. As social concerns override literary ones, writers seem fated to eschew virtuosity and experimentation in favor of a bland but immediately accessible style.”
To Mr. Lanier...the prevalence of mash-ups in today’s culture is a sign of “nostalgic malaise.” “Online culture,” he writes, “is dominated by trivial mash-ups of the culture that existed before the onset of mash-ups, and by fandom responding to the dwindling outposts of centralized mass media. It is a culture of reaction without action.”
He points out that much of the chatter online today is actually “driven by fan responses to expression that was originally created within the sphere of old media,” which many digerati mock as old-fashioned and passé, and which is now being destroyed by the Internet. “Comments about TV shows, major movies, commercial music releases and video games must be responsible for almost as much bit traffic as porn,” Mr. Lanier writes. “There is certainly nothing wrong with that, but since the Web is killing the old media, we face a situation in which culture is effectively eating its own seed stock.”
Klöppel et al. make the interesting observation that plastic changes occur not only in primary sensory-motor cortex but also deep structures of the brain in adult "converted" left-handers who were forced as children to become dextral writers:
Does a conflict between inborn motor preferences and educational standards during childhood impact the structure of the adult human brain? To examine this issue, we acquired high-resolution T1-weighted magnetic resonance scans of the whole brain in adult "converted" left-handers who had been forced as children to become dextral writers. Analysis of sulcal surfaces revealed that consistent right- and left-handers showed an interhemispheric asymmetry in the surface area of the central sulcus with a greater surface contralateral to the dominant hand. This pattern was reversed in the converted group who showed a larger surface of the central sulcus in their left, nondominant hemisphere, indicating plasticity of the primary sensorimotor cortex caused by forced use of the nondominant hand. Voxel-based morphometry showed a reduction of gray matter volume in the middle part of the left putamen in converted left-handers relative to both consistently handed groups. A similar trend was found in the right putamen. Converted subjects with at least one left-handed first-degree relative showed a correlation between the acquired right-hand advantage for writing and the structural changes in putamen and pericentral cortex. Our results show that a specific environmental challenge during childhood can shape the macroscopic structure of the human basal ganglia. The smaller than normal putaminal volume differs markedly from previously reported enlargement of cortical gray matter associated with skill acquisition. This indicates a differential response of the basal ganglia to early environmental challenges, possibly related to processes of pruning during motor development.
Monday, March 22, 2010
This is a recording of a 4-hands Schubert piano piece played in concert in Fort Lauderdale, FL, March 7, 2010, by myself (treble) and David Goldberger (base). Because YouTube has a 10 minutes length limit on videos, I have broken the ~20 minute video into three chunks (parts 1, 2, and 3) which I'm posting on Monday, Wednesday, and Friday of this week.
Zen meditation has been associated with low sensitivity on both the affective and the sensory dimensions of pain. Given reports of gray matter differences in meditators as well as between chronic pain patients and controls, the present study investigated whether differences in brain morphometry are associated with the low pain sensitivity observed in Zen practitioners. Structural MRI scans were performed and the temperature required to produce moderate pain was assessed in 17 meditators and 18 controls. Meditators had significantly lower pain sensitivity than controls. Assessed across all subjects, lower pain sensitivity was associated with thicker cortex in affective, pain-related brain regions including the anterior cingulate cortex, bilateral parahippocampal gyrus and anterior insula. Comparing groups, meditators were found to have thicker cortex in the dorsal anterior cingulate and bilaterally in secondary somatosensory cortex. More years of meditation experience was associated with thicker gray matter in the anterior cingulate, and hours of experience predicted more gray matter bilaterally in the lower leg area of the primary somatosensory cortex as well as the hand area in the right hemisphere. Results generally suggest that pain sensitivity is related to cortical thickness in pain-related brain regions and that the lower sensitivity observed in meditators may be the product of alterations to brain morphometry from long-term practice.
Friday, March 19, 2010
I started taking low doses of a generic statin (Simvastatin) several years ago not because my cholesterol needed lowering, but because I had read about anti-inflammatory effects of the drug. (And it seems to me increases in inflammatory processes are a central issue in aging). Statins also appear to have beneficial effects on the central nervous system. They improve the outcome of stroke and traumatic brain injury, their use has been associated with a reduced prevalence of Alzheimer's disease (AD) and dementia. Man et al (Neuroscience, Volume 166, Issue 2, 17 March 2010, Pages 435-444) have now found that simvastatin, widely used in humans, enhances learning and memory in non-transgenic mice as well as in transgenic mice with AD-like pathology on a mixed genetic background. On looking for mechanisms that might underlie these beneficial effects they find that statins enhance a synaptic process called long term potentiation that is a central component of learning and memory.
An item plucked at random from 'the stream': A new lipstick has gone on sale that the manufacturer claims shows, by changing color, when women are in the mood for sex (by 'reacting with a woman's body chemistry...duh,do I believe this??....maybe temperature sensitive lipstick?)
The lip product changes from clear to deep crimson as the wearer feels more and more frisky. It works by reacting with a woman's body chemistry. Each $18.50 tube comes with a color chart so men can figure out how aroused their partner is feeling. The Mood Swing Emotionally Activated Lip Gloss was invented in California by Too Faced makeup brand."The colors change depending on your emotional state," a spokesperson from Too Faced told The Sun.Celebrity fans include singer Katy Perry, who is engaged to funnyman Russell Brand."This is the ultimate date ice-breaker," dating expert Lorraine Adams said."But using it every day could get embarrassing. Would you really want the man next to you on the bus to know if you're turned on?"
Thursday, March 18, 2010
Lass-Hennemann et al. make the interesting observation that men, who generally prefer mates that resemble themselves, switch to preferring dissimilar mates after they are subjected to a very simple stress procedure (holding their right hand in ice water for three minutes). This conforms with research in animals showing that individuals under stress are willing to mate with a wider variety of partners. Attraction to the images shown was measured by an interesting technique, noting startle eyeblink responses to a burst of white noise. Those in a more upbeat frame of mind (i.e. feeling attraction) flinch less. Scratching around for a possible evolutionary rationale for this behavior, one suggestion is that when conditions seem favorable men have the option of picking physically similar mates, whom they subconsciously deem dependable partners who will nurture their offspring. But in stressful times, during which human survival is less guaranteed, men would be more willing to risk a physically dissimilar partner in order to father as many children as possible.
Here is a figure describing how the stimulus photographs were morphed:
Image editing procedure: the nude woman's detailed face (1) was morphed with the portrait picture of the participant (2). The morphing software produces two output images, a shape-only morph (3a) and a combined shape-colour morph (3b). In a second step, the shape-colour morph is used as a semi-transparent layer on top of the shape-only morph. All artefacts of the morphing procedure are eliminated. The resulting image (4) was photo-mounted on the woman's body in a last step (5). The resulting image was used as a stimulus (the image was not masked in the experiment).
Following the thread of Monday's post on the lost art of the R.S.V.P. , I was struck by this Huffington Post bit on the SXSW (South by Southwest) conference in Austin this past weekend - "Life is but a stream" - that from my point of view points to a future of everyone swirling in a present-centered miasma...
...Activity Streams, Social Objects and a little glimpse into how the data that is our lifestream will grow. And soon.
...SXSW, of course, isn't about the techies, it's about musicians and filmmakers, right? Not so different, as it turns out. They're all developers. All techies. Not just because of the digitization of the music and film industries, but because these are all people who make something from nothing. Inventors. Artists. Creatives. What less people saw coming, I think, was how creative the tech crowd is. How well they fit in and belong with the musicians and movie-makers.
Where does good music come from? Where does great movie writing come from? Some kind of emotional center. So, it was interesting to hear ZeFrank, a guy most people probably refer to as a "viral video maker" talking so much about emotional content. And the guy delivers on it, too. Much of what he has on his site not only will make you think, it reaches you at that emotional center. And it all relies on social experiments.
...Social Objects, Mediated Artifacts and Life Streams are simply techie ways of saying that a system is being engineered that will better capture how you live. That's all. Right now, computers put things into folders, but that's going to change real fast. How? That's not how this works.
If you've written a song, you can relate to this. It's a play between your feeling and the notes available to you. Back and forth. What's happening right now online is that new notes are being added to the scale. What is the future? Listen to the artists. They're all here at SXSW.
Wednesday, March 17, 2010
Adolphs, Damasio, Tranel, and collaborators have published a fascinating open access study in which they report results of having administered standard general intelligence tests to 241 neurologic patients who were being evaluated in connection with their enrollment in the Iowa Cognitive Neuroscience Patient Registry at the University of Iowa, over the course of approximately 2 decades. They found statistically significant associations between g and damage to a remarkably circumscribed, although distributed, network in frontal and parietal cortex, critically including white matter association tracts and frontopolar cortex. They suggest hat general intelligence draws on connections between regions that integrate verbal, visuospatial, working memory, and executive processes. In particular they found a region in the left frontal pole (white circles in Figure 3) that is unique to g and not captured by other subtests. A clip from their discussion:
The largest overlap between WAIS subtests and g was found for Arithmetic, Similarities, Information, and Digit Span; the former two tests also exhibited the greatest conjunction with g. These subtests assess verbal knowledge about the world, verbal reasoning, and abstraction, as well as working memory capacity, and are associated with the left inferior frontal gyrus, the superior longitudinal/arcuate fascicule, and to some degree with parietal cortex (Fig. 3). This suggests that g draws on the combination of conceptual knowledge and working memory, and that the communication between areas associated with these capacities is of crucial importance. Such an interpretation is consistent with the Parieto-Frontal Integration Theory (P-FIT), which postulates roles for cortical regions in the prefrontal (Brodman Area 6, 9–10, 45–47), parietal (BA 7, 39–40), occipital (BA 18–19), and temporal association cortex (BA 21, 37). Our results emphasize the important role of white matter tracts in binding the proposed regions together into a unified system subserving g, in line with a recent study relating white matter integrity to intellectual performance: the study reported significant correlations between integrity of the superior fronto-occipital fasciculus and full-scale intelligence quotient (IQ) (a measure related, but not identical, to g).One of the caveats they mention:
.... Spearman's g disregards theories of multiple intelligences and does not incorporate specific emotional abilities. Therefore we may have isolated an anatomical network important for processing external stimuli, which might operate in parallel with others that are more critical for stimulus reward processing and interoception.
Brooks does a concise piece on how the innate sense of fairness and sympathy that we exhibit towards each other in small groups (as in the U.S. Senate as it used to exist) vanishes when groups are in competition with each other (as in the Senate now). The story of human evolution is the story of competition between groups of humans that are held together internally by more generous and empathetic behaviors than the groups exhibit towards each other. Clips:
In the United States, leaders in the House of Representatives have done an effective job in getting their members to think in group, not person-to-person, terms. Members usually vote as party blocs. Individuals have very little power. That’s why representatives are often subtle and smart as individuals, but crude and partisan as a collective. The social psychology of the House is a clan psychology, not an interpersonal psychology.
The Senate, on the other hand, has historically been home to more person-to-person thinking. This is because the Senate is smaller and because of Senate rules. Until recently, the Senate leaders couldn’t just ram things through on party-line votes. Because a simple majority did not rule, and because one senator had the ability to bring the whole body to a halt, senators had an incentive, every day, to develop alliances and relationships with people in the other party.
But power trumps principle. In nearly every arena of political life, group relationships have replaced person-to-person relationships. The tempo of the Senate is now set by partisan lunches every Tuesday, whereas the body almost never meets for conversation as a whole. The Senate is now in the process of using reconciliation — rule by simple majority — to try to pass health care.
We have a political culture in which the word “reconciliation” has come to mean “bitter division.” With increasing effectiveness, the system bleaches out normal behavior and the normal instincts of human sympathy.
Tuesday, March 16, 2010
Any readers who have checked out my web lectures or podcasts (particularly the "I-Illusion") know how I deal with the topic of free will and determinism. I would recommend that those of you interested in this topic read this excellent open access essay in PNAS by Anthony Cashmore. (Figure 1 is a nice summary of models for the flow of information between unconscious neural activity and conscious thought.) The abstract and a figure:
It is widely believed, at least in scientific circles, that living systems, including mankind, obey the natural physical laws. However, it is also commonly accepted that man has the capacity to make “free” conscious decisions that do not simply reflect the chemical makeup of the individual at the time of decision—this chemical makeup reflecting both the genetic and environmental history and a degree of stochasticism. Whereas philosophers have discussed for centuries the apparent lack of a causal component for free will, many biologists still seem to be remarkably at ease with this notion of free will; and furthermore, our judicial system is based on such a belief. It is the author’s contention that a belief in free will is nothing other than a continuing belief in vitalism—something biologists proudly believe they discarded well over 100 years ago.
Figure (click to enlarge) - Models for the flow of information between unconscious neural activity and conscious thought. In A, the commonly accepted model is shown whereby WILL influences conscious thought and, in turn, unconscious neural activity, to direct behavior. The difficulty with this model is that there is no causal component directing WILL. In B, a causal component for WILL is introduced; however WILL now simply reflects unconscious neural activity and GES (genes, environment, and stochasticism). That is, WILL loses its “freedom.” In C, WILL is dispensed with, and conscious thought is simply a reflection of unconscious neural activity and GES. Conscious thought is now primarily a means of following—more than a means of influencing—the direction of behavior by unconscious neural activity. This subservient role of conscious thought in directing behavior in model C, is indicated by the dotted arrow 2 (contrasting with the solid line for the corresponding arrow in A and B).
Cooper does a NYTimes op-ed piece that perfectly describes my own experience (and frustration) when I have sent out invitations to a music afternoon at my Madison WI. home. It is worth passing on here:
HERE’S an etiquette experiment for you: E-mail an invitation for a party, one month out, to 45 friends. Request an R.S.V.P. Provide a follow-up e-mail message, two weeks later, politely reminding them to get back to you....How many will?...My experiment arose from plans for an evening of food, drink and literature, with readings by myself and two other writers, at a restaurant. Not exactly a drop-in-if-you’re-around kind of thing, so I asked friends to R.S.V.P. My initial message brought in a dozen responses, and the follow-up a few more, but days before the event I had a paltry 23. Not 23 who planned to come, but 23 who had bothered to respond. Half my invitees had blown me off. Why? I wasn’t peddling life insurance, after all.
Asking around, I discovered that the phenomenon is widespread. One friend of mine e-mailed invitations to a baby shower, and a third of the recipients failed to respond. Another announced a happy hour at her house and received a dozen yeses — only to find her party besieged by 35 people....What’s preventing us from executing this basic social task? Is it the medium? Do Evites somehow not feel like “real” invitations? Is it our busy lives, so overbooked and overwhelmed we’ve drawn up the castle gates? Don’t invite me out this month, I’m ensconced! Or is it simple rudeness? Try as I might to understand, I kept feeling dissed.
What’s clear is how hard the R.S.V.P. rubs against the grain of contemporary life. In requesting people to anchor a plan in the distant future of a month hence, you are demanding a kind of navigation that Americans increasingly do not practice. We prefer to remain flexy, solidifying our plans incrementally as the date approaches. Let’s talk tomorrow. I’ll call you when I’m on the road. Cellphones in hand, we microadjust our schedules as they unfold around us. We’re like the air traffic controllers of our own lives.
It wasn’t always so. A while ago I made a lunch date with an elderly couple. As the day approached with no subsequent corroboration, I felt a strange excitement. Would all three of us just show up? We did, and I realized that what I felt was a small nostalgic thrill over social arrangements that seemed straight out of Jane Austen.
But back to my party. The day before the big event, I sent a final e-mail message, thanking “the half of you who responded for helping keep the dying art of the R.S.V.P. alive.” This irked missive flushed out a final 10 hangdog respondents. But there remained a gang of 12 — the dirty dozen, the truly hardcore, fanatical nonresponders — who couldn’t even be shamed into R.S.V.P.ing...In the end, perhaps they were merely following the French literally: Respond, if you please. Left over from a time when graciousness couched demands as requests, the R.S.V.P. no longer functions. I therefore propose an update, something still French but a bit more ... frank — the R.V.O.M.: Répondez Vite — ou Mourir! (Respond Quickly, or Die!)
Monday, March 15, 2010
Lagace et al. look at changes in the dentate gyrus region of the hippocampus to probe why some people are resilient to long-term chronic stress while others develop maladaptive functioning. They examined chronic social defeat stress in a mouse model, finding that synthesis of new nerve cells is increased after social defeat stress selectively in mice that display persistent social avoidance. Irradiation that halts formation of these new nerve cells inhibits appearance of social avoidance, suggesting a functional role for adult-generated dentate gyrus neurons. The data show that the time window after cessation of stress is a critical period for the establishment of persistent cellular and behavioral responses to stress and that a compensatory enhancement in neurogenesis is related to the long-term individual differences in maladaptive responses to stress.
Friday, March 12, 2010
A great article title from Gable and Harmon-Jones, and yet another study involving students in an introductory psychology course: observations that highly motivated positive and negative emotions go with narrowing of our attentional focus, but either positive or negative low-motivation feelings broaden attention. Their slightly edited abstract:
Positive and negative affects high in motivational intensity cause a narrowing of attentional focus. In contrast, positive affects low in motivational intensity cause a broadening of attentional focus. The attentional consequences of negative affects low in motivational intensity have not been experimentally investigated. A first experiment (using color photographs, selected from the International Affective Picture System) compared the attentional consequences of negative affect low in motivational intensity (sadness) relative to a neutral affective state. Results indicated that low-motivation negative affect caused attentional broadening. A second experiment found that disgust, a high-motivation negative affect not previously investigated in attentional studies, narrowed attentional focus. These experiments support the conceptual model linking high-motivation affective states to narrowed attention and low-motivation affective states to broadened attention.
Thursday, March 11, 2010
Kay et al. do some interesting experiments in which thoughts of randomness are primed in subject by a set of manipulations. They:
...supraliminally primed half the participants with randomness-related words; the other half were primed with words matched in negative valence. To assess the role of arousal, we employed a misattribution paradigm, which involved requiring all participants to swallow a pill ostensibly containing an herbal supplement. Half the participants were told that the pill sometimes induces arousal as a side effect, and half were told that the pill has no side effects. Previous work has shown that the side-effect condition leads participants to attribute the cause of any experienced arousal to this salient source. Hypothesizing that beliefs in supernatural control function, at least in part, to down-regulate the aversive arousal associated with randomness, we expected the randomness primes to increase beliefs in God, but only for those participants not given the opportunity to attribute the cause of their arousal to the ingested pill.Their observations were that:
...participants primed with randomness-related words exhibited heightened beliefs in spiritual control compared with participants primed with negatively valenced control words. This effect disappeared when participants were given the opportunity to attribute the cause of any arousal they experienced to a pill ingested earlier in the session.They take their data to suggest:
...that belief in supernatural sources of control, such as God and karma, may function, in part, to defend against distress associated with randomness, even when the perception of randomness is not related to traumatic events.
Male sperm count has dropped dramatically over the past 50 years (~50% in some areas) and one of the prime suspects is estrogen like compounds, such as the pesticide atrazine, that have been introduced into the environment. Atrazine is one of the most commonly applied agricultural pesticides in the world (and, curiously, male sperm count has dropped more in agricultural than in metropolitan areas). Hays et al now show that at levels of only 2.5 parts per billion it can completely feminize amphibian males.
Wednesday, March 10, 2010
Having spent a fair amount of time on the London underground this past summer, I thought this graphic of an imagined world-wide system, shown in the Sunday NYTimes Book Review section, was intriguing.
An imagined train route from Oslo to Pyongyang, from STRANGE MAPS: An Atlas of Cartographic Curiosities (Viking Studio, paper, $30).
Observations from Miller and Manor:
Adaptationist models of human mating provide a useful framework for identifying subtle, biologically based mechanisms influencing cross-gender social interaction. In line with this framework, the current studies examined the extent to which olfactory cues to female ovulation—scents of women at the peak of their reproductive fertility—influence endocrinological responses in men. Men in the current studies smelled T-shirts worn by women near ovulation or far from ovulation (Studies 1 and 2) or control T-shirts not worn by anyone (Study 2). Men exposed to the scent of an ovulating woman subsequently displayed higher levels of testosterone than did men exposed to the scent of a nonovulating woman or a control scent. Hence, olfactory cues signaling women’s levels of reproductive fertility were associated with specific endocrinological responses in men—responses that have been linked to sexual behavior and the initiation of romantic courtship.
Tuesday, March 09, 2010
A further rationale for my sipping red wine during and after dinner - O'Connor notes work showing that red wine does indeed aid the digestion, particularly of dark meats, because it both stimulates digestion and inhibits the formation of harmful oxidized fats.
Posted by Deric Bownds at 8:10 AM
Three recent New York Times pieces have provided a summary of the disintegration of public discourse since the era of Lyndon Johnson. David Carr notes the demise of a short-lived column in The Washington Post on Washington's social life which is symbolic of the passing of the old paradigm, in which
...people with different points of view would assemble in various salons of Georgetown and set aside their differences over an Old Fashioned before the coq au vin was even served...Now the butter knife has been replaced by a machete. People with opposing political points of view are less likely to eat with the loyal opposition at night than to try to dine on them in a quick hit on MSNBC or Fox News... “The dinner party at Ben and Sally’s or Mrs. Graham’s circa 1975 was The Note or Mike Allen blast e-mail of its day,” said David Von Drehle, editor at large for Time and a former editor of The Post’s Style section..."You would go there to see people, try out ideas, figure out what was the interesting next take on the day’s news and where the hot story was headed. But now, you find all that out just by opening up your laptop in the morning.”Articles by both John Harwood and Paul Krugman chronicle the almost perfect polarization that now characterizes the political scene. Harwood:
...when President Lyndon B. Johnson won passage of Medicare, most of the Democratic majority in Congress and half of the Republicans backed him...Those Democratic and Republican parties no longer exist. The kinds of Southern Democrats who resisted Johnson’s agenda and Northern Republicans who supported it have switched parties; longstanding differences between liberals and conservatives are now reinforced by party affiliation, not blurred by it...What democrats and republicans share is a dedication to party unity as an overriding imperative — and a relentlessly improving track record of achieving it.And Krugman focuses on:
...the incredible gap that has opened up between the parties. Today, Democrats and Republicans live in different universes, both intellectually and morally...Democrats believe .. what textbook economics says: that when the economy is deeply depressed, extending unemployment benefits not only helps those in need, it also reduces unemployment...the Congressional Budget Office says that aid to the unemployed is one of the most effective forms of economic stimulus, as measured by jobs created per dollar of outlay. [The view of the second ranking senate Republican, in contrast is that:]... unemployment relief “doesn’t create new jobs. In fact, if anything, continuing to pay people unemployment compensation is a disincentive for them to seek new work.”
...the difference between the two universes isn’t just intellectual, it’s also moral...How can the parties agree on policy when they have utterly different visions of how the economy works, when one party feels for the unemployed, while the other weeps over affluent victims of the “death tax”?..bipartisanship is now a foolish dream...Someday, somehow, we as a nation will once again find ourselves living on the same planet. But for now, we aren’t. And that’s just the way it is.
Monday, March 08, 2010
During a recent period of rehearsing for the four hands piano recital that I participated in yesterday,* I found myself observing (mentally imaging) the detailed execution of the pieces when I woke during the night or early morning. Such imaging is known to be a central part of learning skilled sequences in athletic and musical performance. In a bit of fortuitous timing, the most recent issue of PNAS has an article by Miller et al. describing direct observation of this kind of motor imagery:
Imagery of motor movement plays an important role in learning of complex motor skills, from learning to serve in tennis to perfecting a pirouette in ballet. What and where are the neural substrates that underlie motor imagery-based learning? We measured electrocorticographic cortical surface potentials in eight human subjects during overt action and kinesthetic imagery of the same movement, focusing on power in “high frequency” (76–100 Hz) and “low frequency” (8–32 Hz) ranges. We quantitatively establish that the spatial distribution of local neuronal population activity during motor imagery mimics the spatial distribution of activity during actual motor movement. By comparing responses to electrocortical stimulation with imagery-induced cortical surface activity, we demonstrate the role of primary motor areas in movement imagery. The magnitude of imagery-induced cortical activity change was ∼25% of that associated with actual movement. However, when subjects learned to use this imagery to control a computer cursor in a simple feedback task, the imagery-induced activity change was significantly augmented, even exceeding that of overt movement.*(I have put some rehearsal videos made before the recital here and here, but the final recordings turned out to have technical recording problems and so can't be posted.)
Under the "random curious stuff" category mentioned in MindBlog's title line, I couldn't resist passing on this satirical gem from funnyordie.com
Friday, March 05, 2010
Ferrarelli et al. show what is happening when we are zonked out by an anesthetic like the benzodiazepine midazolam. They use an array of EEG electrodes on the head to measure how much the activities of different areas of the cortex are coordinated with each other when a magnetic pulse is applied to stir things up (transcranial magnetic stimulation, or TMS). When we are awake TMS triggers responses in multiple cortical areas lasting for more than 300 ms, during midazolam-induced loss of consciousness, TMS-evoked activity is shorter and more local, i.e. areas of the cortex stop talking to each other. Here is their abstract:
By employing transcranial magnetic stimulation (TMS) in combination with high-density electroencephalography (EEG), we recently reported that cortical effective connectivity is disrupted during early non-rapid eye movement (NREM) sleep. This is a time when subjects, if awakened, may report little or no conscious content. We hypothesized that a similar breakdown of cortical effective connectivity may underlie loss of consciousness (LOC) induced by pharmacologic agents. Here, we tested this hypothesis by comparing EEG responses to TMS during wakefulness and LOC induced by the benzodiazepine midazolam. Unlike spontaneous sleep states, a subject’s level of vigilance can be monitored repeatedly during pharmacological LOC. We found that, unlike during wakefulness, wherein TMS triggered responses in multiple cortical areas lasting for >300 ms, during midazolam-induced LOC, TMS-evoked activity was local and of shorter duration. Furthermore, a measure of the propagation of evoked cortical currents (significant current scattering, SCS) could reliably discriminate between consciousness and LOC. These results resemble those observed in early NREM sleep and suggest that a breakdown of cortical effective connectivity may be a common feature of conditions characterized by LOC. Moreover, these results suggest that it might be possible to use TMS-EEG to assess consciousness during anesthesia and in pathological conditions, such as coma, vegetative state, and minimally conscious state.
Zuger reviews a book by Judith Warner on a topic that I and many others have had a knee jerk reflex type opinion on: "Yes, of course kids are overmedicated by lazy parents and pill popping psychologists." Warner began her study with that attitude, intending to prove her point, and found quite the opposite. She:
...sallied forth to interview all the pushy parents, irresponsible doctors and overmedicated children she could find — and lo, she could barely find any. After several years of dead ends, missed deadlines and worried soul-searching, she was forced to reconsider her premise and start all over again.
“A couple of simple truths have become clear,” she writes with the passion of a new convert. “That the suffering of children with mental health issues (and their parents) is very real. That almost no parent takes the issue of psychiatric diagnosis lightly or rushes to ‘drug’ his or her child; and that responsible child psychiatrists don’t, either. And that many children’s lives are essentially saved by medication, particularly when it’s combined with evidence-based forms of therapy.”
Thursday, March 04, 2010
I've been meaning to point to an interesting article by Benedict Carey on our voluntary momentary touches that can - whether an exuberant high five, a warm hand on the shoulder, or a creepy touch to the arm — communicate an even wider range of emotion than gestures or expressions, and sometimes do so more quickly and accurately than words. He focuses on work of Dacher Keltner, Hertenstein, and collaborators, the subject of previous posts (PDF here, also, enter Keltner in the search box in the left column). In their experiments volunteers tried to communicate a list of emotions by touching a blindfolded stranger. The participants were able to communicate eight distinct emotions, from gratitude to disgust to love, some with about 70 percent accuracy. Here is their abstract:
The study of emotional communication has focused predominantly on the facial and vocal channels but has ignored the tactile channel. Participants in the current study were allowed to touch an unacquainted partner on the whole body to communicate distinct emotions. Of interest was how accurately the person being touched decoded the intended emotions without seeing the tactile stimulation. The data indicated that anger, fear, disgust, love, gratitude, and sympathy were decoded at greater than chance levels, as well as happiness and sadness, 2 emotions that have not been shown to be communicated by touch to date. Moreover, fine-grained coding documented specific touch behaviors associated with different emotions.A forthcoming publication from Kraus, Huang, and Keltner finds that, with a few exceptions, good basketball teams tended to be touchier than bad ones. Another slightly edited clip:
If a high five or an equivalent can in fact enhance performance, on the field or in the office, that may be because it reduces stress. A warm touch seems to set off the release of oxytocin, a hormone that helps create a sensation of trust, and to reduce levels of the stress hormone cortisol...In the brain, prefrontal areas, which help regulate emotion, can relax, freeing them for another of their primary purposes: problem solving. In effect, the body interprets a supportive touch as “I’ll share the load.”...“We think that humans build relationships precisely for this reason, to distribute problem solving across brains,” said James A. Coan, a a psychologist at the University of Virginia. “We are wired to literally share the processing load, and this is the signal we’re getting when we receive support through touch.”
The same is certainly true of partnerships, and especially the romantic kind, psychologists say. In a recent experiment, researchers led by Christopher Oveis of Harvard conducted five-minute interviews with 69 couples, prompting each pair to discuss difficult periods in their relationship...The investigators scored the frequency and length of touching that each couple, seated side by side, engaged in... "it looks so far like the couples who touch more are reporting more satisfaction in the relationship,” he said. Again, it’s not clear which came first, the touching or the satisfaction. But in romantic relationships, one has been known to lead to the other. Or at least, so the anecdotal evidence suggests.
An interesting tidbit from the Random Samples section of the 19 Feb. issue of Science Magazine:
German scientists have figured out why tomato juice tastes better aboard an airplane than on the ground (and coffee tastes worse). Low atmospheric pressure dampens the experience of sweet and salty tastes whereas sour comes through unchanged and bitter is slightly intensified, says flavor chemist Andrea Burdack-Freitag of the Frauenhofer Institute for Building Physics in Holzkirchen.
She and her colleagues asked 30 taste testers to rate their perceptions of different foods and wine while sitting in a partial Airbus A310 in a chamber with adjustable pressure. At ground pressures, tasters perceived tomato juice as musty, but at a low pressure typical in flight they found it fruitier, with cool notes. The complex aromas picked up by the nose that give coffee its flavor were barely perceived at low pressure, unmasking caffeine's bitterness, Burdack-Freitag says. Lufthansa's catering arm, which sponsored the study, wants to use the data to improve its menus.
Wednesday, March 03, 2010
Here is an interesting open access article from Ralph Adolphs and his colleagues:
Losses are a possibility in many risky decisions, and organisms have evolved mechanisms to evaluate and avoid them. Laboratory and field evidence suggests that people often avoid risks with losses even when they might earn a substantially larger gain, a behavioral preference termed “loss aversion.” The cautionary brake on behavior known to rely on the amygdala is a plausible candidate mechanism for loss aversion, yet evidence for this idea has so far not been found. We studied two rare individuals with focal bilateral amygdala lesions using a series of experimental economics tasks. To measure individual sensitivity to financial losses we asked participants to play a variety of monetary gambles with possible gains and losses. Although both participants retained a normal ability to respond to changes in the gambles’ expected value and risk, they showed a dramatic reduction in loss aversion compared to matched controls. The findings suggest that the amygdala plays a key role in generating loss aversion by inhibiting actions with potentially deleterious outcomes.
I have done a large number of posts on behavioral effects of oxytocin, the 'trust hormone', notably in human studies that use an oxytocin inhaler (enter oxytocin in the blog search box in the left column to display them). Recent studies are now suggesting that when some autistic people (who have difficulty interacting with others) inhale oxytocin, they began looking at people in the eye and recognizing social concepts like fairness in a computer game.
Tuesday, March 02, 2010
I am increasingly amazed at the creeping "pathologicalization" of behaviors that vary a bit from the 'normal'. Almost any repetitive activity or habit could be construed as a behavioral addition (Tiger Wood's golf and sex?). I might well be considered an alcoholic sociopathic sex addict by some, given my one a day knockout happy hour drink, my extremely active libido, and my ability to observe the generation of my emotional and social behaviors and halt or detach from them when necessary. I though this article by Constance Holden had some interesting chunks, which I pass on here (see also the related previous post yesterday on the Bonkers institute):
"...proposed revisions for the American Psychiatric Association's (APA's) Diagnostic and Statistical Manual of Mental Disorders (DSM) include for the first time "behavioral addictions"—a change some say is long overdue and others say is still premature...
"Sex addiction" has received a lot of press lately, but O'Brien [University of Pennsylvania, chair of the addictions work group for DSM-V] says his work group found "no scientific evidence" that sex qualifies. APA psychiatrist Darrel Regier, co-chair of the DSM task force, says "it's not clear that reward circuitry is operative in the same way as in addictive areas." Nonetheless, a near equivalent may make it into the sexual disorders section of DSM: That work group is proposing a controversial new diagnosis of "hypersexual disorder."
The DSM teams have also tussled with the often-blurry line between addictions and compulsions. "I used to think [addictions] overlapped with OCD [obsessive-compulsive disorder]," says O'Brien. But new data from both brain-imaging and treatment studies suggest "more dissimilarities than similarities."
In another major change, O'Brien's group recommends dropping categories of "abuse" and "dependence" and labeling all problems major and minor as substance "use disorders" (or "disordered gambling"). Since the late 1980s, says O'Brien, "numerous large population studies" have shown there's no "breakpoint" where "abuse" becomes something more serious. He also says the term "dependence" only implies physiological dependence, which is not the same as the psychological obsession of addiction.
Some longtime addiction researchers, such as psychiatrist Victor Hesselbrock of the University of Connecticut, Farmington, have qualms about the direction DSM is moving. Hesselbrock believes behavioral addictions are dicey territory and prefers to limit the term "addiction" to substances, which are "pathogens we can identify." He also objects to fusing all drinking problems into "alcohol use disorder." Hesselbrock says he and others think there are proven subcategories of alcoholism that would aid both in treatment and discovering causes. "When you do a one-size-fits-all type of classification system," he says, "that will fit a lot of people but not so well."
Magnin et al. have recorded thalamic and cortical activities simultaneously in epileptic patients chronically implanted with intracerebral electrodes to address the issue of when these two regions of the brain go to sleep. (The thalamus is the main gateway through which information from our bodies flows to the cortex.) They find, contrary to the common view, that the thalamus deactivates well before the cortex during sleep onset, leaving the cortex to spin its stories without input from the world during a hypnagogic or half-awake state during which illusions or inspirations sometimes occur, giving us the impression that it is taking us longer to get to sleep than is actually the case. Here is their abstract:
Thalamic and cortical activities are assumed to be time-locked throughout all vigilance states. Using simultaneous intracortical and intrathalamic recordings, we demonstrate here that the thalamic deactivation occurring at sleep onset most often precedes that of the cortex by several minutes, whereas reactivation of both structures during awakening is synchronized. Delays between thalamus and cortex deactivations can vary from one subject to another when a similar cortical region is considered. In addition, heterogeneity in activity levels throughout the cortical mantle is larger than previously thought during the descent into sleep. Thus, asynchronous thalamo-cortical deactivation while falling asleep probably explains the production of hypnagogic hallucinations by a still-activated cortex and the common self-overestimation of the time needed to fall asleep.
Monday, March 01, 2010
Jonah Lehrer (a really bright guy, author of "How We Decide", "Proust was a Neuroscientist", and the blog "The Frontal Cortex") has made his first New York Times Magazine contribution, an excellent article on depression that focuses on work of Andrews and Thomson who suggest that depression is a evolved behavior that has the function of removing us from normal daily behaviors to focus on and hopefully solve a pressing life issue. They describe their model as the "analytic-rumination hypothesis." A few clips from the article:
Several studies found an increase in brain activity (as measured indirectly by blood flow) in the VLPFC of depressed patients. Most recently, a paper to be published next month by neuroscientists in China found a spike in “functional connectivity” between the lateral prefrontal cortex and other parts of the brain in depressed patients, with more severe depressions leading to more prefrontal activity. One explanation for this finding is that the hyperactive VLPFC underlies rumination, allowing people to stay focused on their problem...the reliance on the VLPFC doesn’t just lead us to fixate on our depressing situation; it also leads to an extremely analytical style of thinking. That’s because rumination is largely rooted in working memory, a kind of mental scratchpad that allows us to “work” with all the information stuck in consciousness. When people rely on working memory — and it doesn’t matter if they’re doing long division or contemplating a relationship gone wrong — they tend to think in a more deliberate fashion, breaking down their complex problems into their simpler parts.In the last section of the article Lehrer notes a number of studies indicating a correlation of depression with better artistic creativity and improved analytical abilities.
The bad news is that this deliberate thought process is slow, tiresome and prone to distraction; the prefrontal cortex soon grows exhausted and gives out. Andrews and Thomson see depression as a way of bolstering our feeble analytical skills, making it easier to pay continuous attention to a difficult dilemma. The downcast mood and activation of the VLPFC are part of a “coordinated system” that, Andrews and Thomson say, exists “for the specific purpose of effectively analyzing the complex life problem that triggered the depression.” If depression didn’t exist — if we didn’t react to stress and trauma with endless ruminations — then we would be less likely to solve our predicaments. Wisdom isn’t cheap, and we pay for it with pain.
....the analytic-rumination hypothesis is merely the latest attempt to explain the prevalence of depression. There is, for example, the “plea for help” theory, which suggests that depression is a way of eliciting assistance from loved ones. There’s also the “signal of defeat” hypothesis, which argues that feelings of despair after a loss in social status help prevent unnecessary attacks; we’re too busy sulking to fight back. And then there’s “depressive realism”: several studies have found that people with depression have a more accurate view of reality and are better at predicting future outcomes. While each of these speculations has scientific support, none are sufficient to explain an illness that afflicts so many people. The moral, Nesse says, is that sadness, like happiness, has many functions.
To say that depression can be useful doesn't mean it is always going to be useful. While it might explain patients reacting to an acute stressor, it can’t account for those whose suffering has no discernible cause or whose sadness refuses to lift for years at a time.
The distinguished Dr. Methodius Bonkers has emailed me to point out his institute's most recent study. It is a hoot.