Judging honesty by story telling.

Benedict Carey summarizes work on detecting lying, not by body language cues, but by what people say. People telling the truth tend to add 20 to 30 percent more external detail than do those who are lying. If you’re telling the truth, this mental reinstatement of contexts triggers more and more external details. Not so if you’ve got a concocted story and you’re sticking to it. “It’s the difference between a tree in full flower in the summer and a barren stick in winter."

Antioxidants bad for you?

Check out this open access article by Ristow and et al.

Ramachandran and the plastic brain.

John Colapinto writes a New Yorker article on Vilayanur Ramachandran, whose work I have mentioned several times (actually, in six postings...enter Ramachandran in the search box in the left column to bring them up.) It is a biographical account, describing Ramachandran's professional development, and also describes an interesting syndrome known as apotemnophilia, the compulsion to have a healthy limb amputated. It appears to result from damage to the right superior parietal lobe which causes it to fail in assembling a normal body image for the body part perceived as alien, wanting amputation. Just as was the case with phantom limb pain and stroke induced paralysis, Ramachandran found that use of a simple mirror to differently present a body part could alleviate the symptoms. The article also describes work which suggests a link between autism and defects in the mirror neuron system.

Misconceptions of Memory: The Scooter Libby Effect

Some clips from a recent article from Daniel Gilbert and collaborators (Gilbert is the guy who wrote "Stumbling on Happiness" that I abstracted several years ago on this blog):

...during his 2007 trial, Vice-Presidential Chief of Staff I. Lewis "Scooter" Libby claimed that he could not remember mentioning the identity of a Central Intelligence Agency employee to other government officials or reporters. Jurors found it difficult to believe that Libby could have forgotten having had such important conversations and found him guilty of obstruction of justice, making false statements, and perjury
...Libby's conversations were indeed important, but they were less important at the time he had them than they became months later when the Justice Department launched its investigation. Although important information increases the motivation to remember (MTR), research on human memory suggests that MTR is considerably more effective when it arises before rather than after information is encoded...Do people take the timing of MTR into account when judging other people's memories?

Here is the experimental design:

Memorizers were told that they would study the material for 2 min before seeing the photographs and trying to recall the facts associated with each. They were also told that they would receive $0.10 for each recalled fact. Before they studied the material, memorizers in the MTR-at-encoding condition (n= 21) were told that they would receive a $0.50 bonus for each fact they remembered about the individual named Beryl White. Memorizers in the MTR-at-retrieval condition (n= 22) were told about this bonus immediately after they studied the material. Memorizers in the no-MTR condition (n= 21) were not told about the bonus. After studying the material, memorizers were shown the photograph of Beryl White and were asked to recall the facts about her.

Judges were shown the same material as memorizers and read a detailed description of the instructions from the MTR-at-encoding condition (n= 24), the MTR-at-retrieval condition (n= 21), or the no-MTR condition (n= 21). Judges were then asked to predict the percentage of memorizers in that condition who would remember each fact.

The results, shown in this figure, were extremely clear:

Participants who were asked to judge another individual's memory did not distinguish between information that was important when the individual encountered it and information that became important only later. Clearly, people's theories about the effects of motivation on memory are imperfect. It is interesting to note, in light of these findings, that the U.S. District Court denied Libby's motion to allow expert psychologists to testify about the foibles of memory and metamemory because, the court argued, such research would tell jurors little that they did not already know.

Brain correlates of self-transcendent emotions

Antonio and Hanna Damasio and collaborators have now observed brain activities associated with our internal loftier emotions that transcend self-interest, such as elevation and admiration. These are hard to measure because they don't correlate obviously with facial expressions or body language. Haidt and Morris, in their commentary in the same issue of PNAS, set the context for the work:

Emotion research has something in common with a drunk searching for his car keys under a street lamp. ‘‘Where did you lose them?’’ asks the cop. ‘‘In the alley,’’ says the drunk, ‘‘but the light is so much better over here.’’ For emotion research, the light shines most brightly on the face, whose movements can be coded, compared across cultures, and quantified by electromyography. All of the ‘‘basic’’ emotions described by Paul Ekman and others (happiness, sadness, anger, fear, surprise, and disgust) earned their place on the list by being face-valid. The second source of illumination has long been animal research. Emotions that can be reliably triggered in rats, such as fear and anger, have been well-studied, down to specific pathways through the amygdala. But emotions that cannot be found on the face or in a rat, such as moral elevation and admiration, are largely abandoned back in the alley. We know they are there, but nobody can seem to find a flashlight. It is therefore quite an achievement that Immordino-Yang, McCall, Damasio, and Damasio managed to drag an fMRI scanner back there and have given us a first glimpse of the neurological underpinnings of elevation and admiration.

Here is the abstract and a figure from the paper:

In an fMRI experiment, participants were exposed to narratives based on true stories designed to evoke admiration and compassion in 4 distinct categories: admiration for virtue (AV), admiration for skill (AS), compassion for social/psychological pain (CSP), and compassion for physical pain (CPP). The goal was to test hypotheses about recruitment of homeostatic, somatosensory, and consciousness-related neural systems during the processing of pain-related (compassion) and non-pain-related (admiration) social emotions along 2 dimensions: emotions about other peoples' social/psychological conditions (AV, CSP) and emotions about others' physical conditions (AS, CPP). Consistent with theoretical accounts, the experience of all 4 emotions engaged brain regions involved in interoceptive representation and homeostatic regulation, including anterior insula, anterior cingulate, hypothalamus, and mesencephalon. However, the study also revealed a previously undescribed pattern within the posteromedial cortices (the ensemble of precuneus, posterior cingulate cortex, and retrosplenial region), an intriguing territory currently known for its involvement in the default mode of brain operation and in self-related/consciousness processes: emotions pertaining to social/psychological and physical situations engaged different networks aligned, respectively, with interoceptive and exteroceptive neural systems. Finally, within the anterior insula, activity correlated with AV and CSP peaked later and was more sustained than that associated with CPP. Our findings contribute insights on the functions of the posteromedial cortices and on the recruitment of the anterior insula in social emotions concerned with physical versus psychological pain.


Figure (click to enlarge). Relative activation in the posteromedial cortices (PMC, outlined in pink) for admiration for virtue and compassion for social pain (AV/CSP, blue3 green) versus admiration for skill and compassion for physical pain (AS/CPP, orange 3 yellow). The image is thresholded at q(FDR)  0.05. The bar to the right provides a color code for t statistics associated with the contrast. The red box frames the location of the magnified view. Note the clear separation between the anterosuperior sector activated by AS/CPP, and the posteroinferior activated by AV/CSP.

As an added note: The commentary by Haidt and Morris offers an interesting table summarizing the number of articles on the main moral emotions other than compassion (on which a lot has been done), showing the number of articles in the PsycINFO database for which the emotion name was in the title or keywords fields.

The amazing aging brain - continued

This website on aging created by the Oregon Museum of Science and Industry has shifted locations quite a bit since I first mentioned it. My thanks to MindBlog reader Maryann S. Marino for tracking it down.

Gross national happiness

Seth Mydans describes how the tiny Himalayan kingdom of Bhutan (population ~700,000) is making an effort to replace GNP (gross national product) with GNH (gross national happiness) as the most meaningful indicator of a nation's health. After the World Bank and the I.M.F. essentially said OK.......but how do you measure it?, the government devised an intricate model of well-being, that in true Buddhist form, gets into huge lists and sub-lists: the four pillars, nine domains, and 72 indicators of happiness.

Gross national happiness has a broader application for Bhutan as it races to preserve its identity and culture from the encroachments of the outside world...Bhutan is pitting its four pillars, nine domains and 72 indicators against the 48 channels of Hollywood and Bollywood that have invaded since television was permitted a decade ago...Before June 1999 if you asked any young person who is your hero, the inevitable response was, ‘The king,’ Immediately after that it was David Beckham, and now it’s 50 Cent, the rap artist. Parents are helpless...So if G.N.H. may hold the secret of happiness for people suffering from the collapse of financial institutions abroad, it offers something more urgent here in this pristine culture.

The neuroeconomics of taking your pick.

Whaley offers a summary of papers by Martino et al. (open access) and Sharot et al. in a recent issue of J. Neurosci and a more recent paper by Croxson et al. notes correlates of cost-benefits valuation. Excerpts from Whaley:

To deal with the countless decisions that it makes, the brain must assign values to each available option. However, the perceived value of an option can be influenced by multiple factors. Two recent papers shed light on the brain regions involved in the neural representation of value.

Choosing between several equally appealing options is difficult; however, once a decision is made, our expectations of our chosen option's value often become inflated with respect to that of the rejected alternatives. Sharot et al. carried out functional MRI (fMRI) of participants as they estimated how much they would enjoy vacationing in various destinations before and after choosing one of two equally rated vacations. This demonstrated that the relative sizes of the blood oxygen level-dependent (BOLD) signals in the caudate nucleus in response to the initial presentation of the destinations predicted subsequent choices. As expected, after making their selection, participants rated their chosen destination higher than the rejected destination. Furthermore, the differences in the caudate nucleus BOLD signal response to selected versus rejected options increased after the selection, suggesting that the act of choosing can itself alter the neurobiological representation of an option's value.

The 'endowment effect' is our tendency to value objects that we own and are selling more highly than identical objects belonging to others that we are thinking of buying. It is thought to arise because an object's value with respect to a reference point (in this case, owning the item) is altered by the individual's position as buyer or seller in the transaction. De Martino et al. asked participants how much they would accept in payment for or spend on lottery tickets with different expected payoffs. fMRI showed that activity in the ventral striatum correlated highly with the behavioural tendency to overvalue items when selling and undervalue items when buying, suggesting that this region contributes to the reference-dependent valuation of items.

These two studies provide insights into some of the neural mechanisms involved in encoding value in the brain and how these representations may be altered by previous decisions or social context.

Are E-readers our future?

I certainly hope not, based on my experience with the Amazon Kindle ^* - compared with a normal book, hopelessly slow, hard to jump around easily. And forget trying anything but fiction and simple text. I've read some of the psychology books I've mentioned on the Kindle, and tables and references are either screwed up or simply not there. And for the fiction that I still read on an E-reader, I find the iPhone Kindle App more congenial that my original Kindle, because I'm carrying around the iPhone all the time anyway. This article by Brad Stone, on how E-readers might save newspapers, is a nice summary of some of the issues. Any large thin tablet device will have to have color graphic and videos, like our current computers (Apple is said to be working on one). I don't think I'm going to be happy even with that, because the NYTimes.com site that I frequently use to excerpt stuff for this blog isn't as much fun as the real newspaper - which allows you to jump around more rapidly and easily in the content using our primitive biological search appendages - arms and hands. (Added note: a larger version of the Kindle has just been announced, which I still think doesn't cut it.)

^*(An interesting fact arises from looking at the Kindle user base. Half of reporting Kindle owners are 50 or older, and 70 percent are 40 or older. Many report buying a Kindle because of a variety of impairments: hand arthritis, weakening eyes, etc.)

Faith in flux...

The Pew Forum has put out an interesting study with the title of this post. From a summary by Blow:

..most children raised unaffiliated with a religion later choose to join one...While science, logic and reason are on the side of the nonreligious, the cold, hard facts are just so cold and hard. Yes, the evidence for evolution is irrefutable. Yes, there is a plethora of Biblical contradictions. Yes, there is mounting evidence from neuroscientists that suggests that God may be a product of the mind. Yes, yes, yes. But when is the choir going to sing? And when is the picnic? And is my child going to get a part in the holiday play?

As the nonreligious movement picks up steam, it needs do a better job of appealing to the ethereal part of our human exceptionalism — that wondrous, precious part where logic and reason hold little purchase, where love and compassion reign. It’s the part that fears loneliness, craves companionship and needs affirmation and fellowship...Being regularly surrounded by a community that shares your convictions and reinforces them through literature, art and ritual is incredibly powerful, and yes, spiritual.

Issue of our times: concentration versus distractability

John Tierny does a great article on the science of concentration. I know this is a huge issue for me. I find that my constant scanning of tables of contents of various journals for tidbits that might go in this blog leaves my attention constantly flitting about, as I feel like an overstuffed goose that continues to peck around ingesting more random pieces than can be properly digested. While attending to a task I am easily distracted (a documented feature of aging!). Here are some clips from Tierny's article, which notes the recent book “Rapt,” a guide by Winifred Gallagher to the science of paying attention. The book's theme:

...is borrowed from the psychologist William James: “My experience is what I agree to attend to.” You can lead a miserable life by obsessing on problems. You can drive yourself crazy trying to multitask and answer every e-mail message instantly...Or you can recognize your brain’s finite capacity for processing information, accentuate the positive and achieve the satisfactions of what Ms. Gallagher calls the focused life.

The work of Desimone and collaborators at MIT is mentioned:

When something bright or novel flashes, it tends to automatically win the competition for the brain’s attention, but that involuntary bottom-up impulse can be voluntarily overridden through a top-down process that Dr. Desimone calls “biased competition.” He and colleagues have found that neurons in the prefrontal cortex — the brain’s planning center — start oscillating in unison and send signals directing the visual cortex to heed something else.

Now that neuroscientists have identified the brain’s synchronizing mechanism, they’ve started work on therapies to strengthen attention. In the current issue of Nature, researchers from M.I.T., Penn and Stanford report that they directly induced gamma waves in mice by shining pulses of laser light through tiny optical fibers onto genetically engineered neurons. In the current issue of Neuron, Dr. Desimone and colleagues report progress in using this “optogenetic” technique in monkeys.

Ultimately, Dr. Desimone said, it may be possible to improve your attention by using pulses of light to directly synchronize your neurons, a form of direct therapy that could help people with schizophrenia and attention-deficit problems (and might have fewer side effects than drugs). If it could be done with low-wavelength light that penetrates the skull, you could simply put on (or take off) a tiny wirelessly controlled device that would be a bit like a hearing aid.

Further comments from Gallagher, who:

...advocates meditation to increase your focus, but...there are also simpler ways to put the lessons of attention researchers to use. Once she learned how hard it was for the brain to avoid paying attention to sounds, particularly other people’s voices, she began carrying ear plugs with her. When you’re trapped in a noisy subway car or a taxi with a TV that won’t turn off, she says you have to build your own “stimulus shelter.”...She recommends starting your work day concentrating on your most important task for 90 minutes. At that point your prefrontal cortex probably needs a rest, and you can answer e-mail, return phone calls and sip caffeine (which does help attention) before focusing again. But until that first break, don’t get distracted by anything else, because it can take the brain 20 minutes to do the equivalent of rebooting after an interruption. (For more advice, go to nytimes.com/tierneylab.)

“Multitasking is a myth,” Ms. Gallagher said. “You cannot do two things at once. The mechanism of attention is selection: it’s either this or it’s that.” She points to calculations that the typical person’s brain can process 173 billion bits of information over the course of a lifetime....“People don’t understand that attention is a finite resource, like money,” she said. “Do you want to invest your cognitive cash on endless Twittering or Net surfing or couch potatoing? You’re constantly making choices, and your choices determine your experience, just as William James said.”

Civilization has caused the decline of human health

I've just finished reading Michael Pollan's "In Defense of Food: An Eater's Manifesto," which is a scary documentation of how modern food technology and 'nutritionism' have significantly increased obesity, diabetes and coronary disease in this century, particularly since the second world war. Thus Ann Gibbons' summary (from presentations at the recent Americal Assoc. of Physical Anthropologists' meeting) of the effects of our earlier transition from hunting/gathering to agriculture makes a lot of sense. A major project has pooled work from 72 researchers to provide the first analysis of data on 11,000 individuals who lived from 3000 years ago until 200 years ago throughout Europe and the Mediterranean. The analysis involves standardized indicators of health from skeletal remains, including stature, dental health, degenerative joint disease, anemia, trauma, and the isotopic signatures of what they ate.

...the health of many Europeans began to worsen markedly about 3000 years ago, after agriculture became widely adopted in Europe and during the rise of the Greek and Roman civilizations. They document shrinking stature and growing numbers of skeletal lesions from leprosy and tuberculosis, caused by living close to livestock and other humans in settlements where waste accumulated. The numbers of dental hypoplasias and cavities also increased as people switched to a grain-based diet with fewer nutrients and more sugars...After a long, slow decline through the Middle Ages, health began to improve in the mid-19th century. Stature increased, probably because of several factors: The little Ice Age ended and food production rose, and better trade networks, sanitation, and medicine developed... But take heed: Overall health and stature in the United States has been declining slightly since the 1950s, possibly because obese Americans eat a poor-quality diet, not unlike early farmers whose diet was less diverse and nutritious than that of hunter-gatherers.

Playing video games improves basic visual function.

Playing action-based video games has been shown to improve attentional processing. Li et al. now find that it also induces long-lasting improvements in contrast sensitivity, a basic visual function that commonly deteriorates with age. These improvements do not happen for an equivalent group who played a non-action video game. Contrast sensitivity is one of the main limiting factors in a wide variety of visual tasks, and it is one of the aspects of vision that is most easily compromised. Here is a useful illustration of contrast sensitivity, from an accompanying review of their work (click to enlarge).

Stimulus contrast and tests of visual function - Top, examples of low- (left) and high-contrast (right) sine wave gratings. Simple stimuli such as these are often used in perceptual learning experiments. Bottom left, an example of a Snellen Eye chart used to measure visual acuity. Bottom right, an example of a Campbell-Robson contrast sensitivity function chart. To see your own contrast sensitivity function, look toward the top of the chart, where the white-black modulations should 'blend in' with the gray background. The inverted-U shaped curve that you see indicates that contrast sensitivity is better for mid-range spatial frequencies than for low or high ones. Playing action-based video games improves contrast sensitivity, effectively 'pushing' this curve upwards.

Special nerves for pleasant social touch.

Neural correlates of pleasure have been studied mainly in our central nervous systems (brain and spinal cord). Löken et al., look at activity in our peripheral nervous system, specifically a small class of axons without myelin wrapping that send pressure information from skin to the central nervous system. They demonstrate a relationship between positive hedonic sensation and coding at the level of these peripheral afferent nerves, suggesting that C-tactile fibers contribute critically to pleasant touch. Soft brush stroking on hairy skin was perceived as most pleasant when it was delivered at velocities that were most effective at activating C-tactile afferents (1–10 cm s-1), with a linear correlation between C-tactile impulse frequency and pleasantness ratings. Here is the abstract:

Pleasant touch sensations may begin with neural coding in the periphery by specific afferents. We found that during soft brush stroking, low-threshold unmyelinated mechanoreceptors (C-tactile), but not myelinated afferents, responded most vigorously at intermediate brushing velocities (1-10 cm s^-1), which were perceived by subjects as being the most pleasant. Our results indicate that C-tactile afferents constitute a privileged peripheral pathway for pleasant tactile stimulation that is likely to signal affiliative social body contact.

Monday morning music - Chopin Nocturne in C# minor - posthumous

I've finally gotten through re-entry details after my return to Wisconsin, and started recording some pieces -using the Steinway B in my home on Twin Valley Rd. in the Town of Middleton, just west of Madison, WI. (The pictures below the video are spring flowers in the front yard that I can see from the piano.) This reading of the posthumous Chopin Nocturne in C# minor is a more rapid and robust one than many. I may decide to do it again, or do a second version.

Risk-dependent reward value signal in human prefrontal cortex

From Tobler et al., observations on brain activity during risk-reward situations that emphasize lateral prefrontal cortex, while the risk-reward study referenced in my April 25 post points at ventral medial prefrontal cortex. It is because of this kind of variation in results reported by different labs that one has to wait a bit for a concensus to emerge on structure-function correlations. Here is the Tobler et al. abstract:

When making choices under uncertainty, people usually consider both the expected value and risk of each option, and choose the one with the higher utility. Expected value increases the expected utility of an option for all individuals. Risk increases the utility of an option for risk-seeking individuals, but decreases it for risk averse individuals. In 2 separate experiments, one involving imperative (no-choice), the other choice situations, we investigated how predicted risk and expected value aggregate into a common reward signal in the human brain. Blood oxygen level dependent responses in lateral regions of the prefrontal cortex increased monotonically with increasing reward value in the absence of risk in both experiments. Risk enhanced these responses in risk-seeking participants, but reduced them in risk-averse participants. The aggregate value and risk responses in lateral prefrontal cortex contrasted with pure value signals independent of risk in the striatum. These results demonstrate an aggregate risk and value signal in the prefrontal cortex that would be compatible with basic assumptions underlying the mean-variance approach to utility.

Our amygdala is more responsive to pleasant words

Interesting observations from Herbert et al. Some brain correlates of how we remember pleasant better than unpleasant reading content. Their event-related functional magnetic resonance imaging (fMRI) study:

...investigated brain activity elicited by emotional adjectives during silent reading without specific processing instructions. Fifteen healthy volunteers were asked to read a set of randomly presented high-arousing emotional (pleasant and unpleasant) and low-arousing neutral adjectives. Silent reading of emotional in contrast to neutral adjectives evoked enhanced activations in visual, limbic and prefrontal brain regions. In particular, reading pleasant adjectives produced a more robust activation pattern in the left amygdala and the left extrastriate visual cortex than did reading unpleasant or neutral adjectives. Moreover, extrastriate visual cortex and amygdala activity were significantly correlated during reading of pleasant adjectives. Furthermore, pleasant adjectives were better remembered than unpleasant and neutral adjectives in a surprise free recall test conducted after scanning. Thus, visual processing was biased towards pleasant words and involved the amygdala, underscoring recent theoretical views of a general role of the human amygdala in relevance detection for both pleasant and unpleasant stimuli. Results indicate preferential processing of pleasant information in healthy young adults and can be accounted for within the framework of appraisal theory.

Reminders of age undermine memory

Nagourny notes a study in which researchers found that when older volunteers took a series of cognitive tests after being given hints that their age might affect the results, they did less well.

REM sleep enhances storage of emotional memories

From Nishida et al:

Both emotion and sleep are independently known to modulate declarative memory. Memory can be facilitated by emotion, leading to enhanced consolidation across increasing time delays. Sleep also facilitates offline memory processing, resulting in superior recall the next day. Here we explore whether rapid eye movement (REM) sleep, and aspects of its unique neurophysiology, underlie these convergent influences on memory. Using a nap paradigm, we measured the consolidation of neutral and negative emotional memories, and the association with REM-sleep electrophysiology. Subjects that napped showed a consolidation benefit for emotional but not neutral memories. The No-Nap control group showed no evidence of a consolidation benefit for either memory type. Within the Nap group, the extent of emotional memory facilitation was significantly correlated with the amount of REM sleep and also with right-dominant prefrontal theta power during REM. Together, these data support the role of REM-sleep neurobiology in the consolidation of emotional human memories, findings that have direct translational implications for affective psychiatric and mood disorders.

Friends and a long life.

I have been meaning to pass on this article by Parker-Pope, which notes several studies on the correlation between social networks, longevity, and psychological well-being.