Friday, January 02, 2015

Biological explanations for psychopathology decrease clinician empathy.

Lebowitz and Ahn find that clinicians become less, not more, empathetic with patients whose mental disorder is known to have a biological basis:
Mental disorders are increasingly understood in terms of biological mechanisms. We examined how such biological explanations of patients’ symptoms would affect mental health clinicians’ empathy—a crucial component of the relationship between treatment-providers and patients—as well as their clinical judgments and recommendations. In a series of studies, US clinicians read descriptions of potential patients whose symptoms were explained using either biological or psychosocial information. Biological explanations have been thought to make patients appear less accountable for their disorders, which could increase clinicians’ empathy. To the contrary, biological explanations evoked significantly less empathy. These results are consistent with other research and theory that has suggested that biological accounts of psychopathology can exacerbate perceptions of patients as abnormal, distinct from the rest of the population, meriting social exclusion, and even less than fully human. Although the ongoing shift toward biomedical conceptualizations has many benefits, our results reveal unintended negative consequences.

Thursday, January 01, 2015

Cerebral coherence between communicators.

Stolk et al. have searched across the whole brain for a cerebral dynamics matching the behavioral dynamics of mutual understanding and note that brain activities in the right temporal lobes of individuals synchronize during communication in a way that reflects conceptualization of a signal's use apart from specific experiences of the signal:
How can we understand each other during communicative interactions? An influential suggestion holds that communicators are primed by each other’s behaviors, with associative mechanisms automatically coordinating the production of communicative signals and the comprehension of their meanings. An alternative suggestion posits that mutual understanding requires shared conceptualizations of a signal’s use, i.e., “conceptual pacts” that are abstracted away from specific experiences. Both accounts predict coherent neural dynamics across communicators, aligned either to the occurrence of a signal or to the dynamics of conceptual pacts. Using coherence spectral-density analysis of cerebral activity simultaneously measured in pairs of communicators, this study shows that establishing mutual understanding of novel signals synchronizes cerebral dynamics across communicators’ right temporal lobes. This interpersonal cerebral coherence occurred only within pairs with a shared communicative history, and at temporal scales independent from signals’ occurrences. These findings favor the notion that meaning emerges from shared conceptualizations of a signal’s use.

Wednesday, December 31, 2014

Neurobiology and the Humanities

I want to point to this open access article in Neuron by Semir Zeki, a well known visual neuroanatomist who has addressed in particular visual artists - who, in engaging representations of form and color, explore the brain with techniques that are unique to them. Here is an early clip from the relatively brief article, which I think you might enjoy reading, that proceeds to consider the experience, significance, and uses of beauty.:
Paul Cézanne’s preoccupation, and artistic experimentation, with how color modulates form is but a variant of the neurobiological question of how the separate representations of form and color are integrated in the brain to give us a unitary percept of both. The experiments of Picasso and Braque in the early, analytic, phase of cubism—of how a form maintains its identity in spite of wide variations in the context in which it is viewed—resolves itself scientifically into the neurobiological problem of form constancy. The quest of Piet Mondrian for the “constant truths concerning forms” is an artistic version of the question of what the neural building blocks of all forms are (often presumed to be the orientation-selective cells of the visual cortex), while kinetic art, which sought to represent motion artistically, reached conclusions that are consistent with conclusions reached later by neurobiology.

Tuesday, December 30, 2014

Origins of human altruism.

A number of studies in recent years have shown that 1- and 2-year-olds often provide help to novel individuals, and have generally been interpreted as suggesting that this tendency is innate, and unlikely to result from social interactions. Barragan and Dweck offer observations to the contrary, finding that very simple reciprocal social activities at these ages can elicit high degrees of altruism. The experiments involved reciprocal play (two individuals playing with one set of toys from a bag) or parallel play (two individuals playing separately with identical sets of toys taken from two bags.) Here is their abstract:
A very simple reciprocal activity elicited high degrees of altruism in 1- and 2-y-old children, whereas friendly but nonreciprocal activity yielded little subsequent altruism. In a second study, reciprocity with one adult led 1- and 2-y-olds to provide help to a new person. These results question the current dominant claim that social experiences cannot account for early occurring altruistic behavior. A third study, with preschool-age children, showed that subtle reciprocal cues remain potent elicitors of altruism, whereas a fourth study with preschoolers showed that even a brief reciprocal experience fostered children’s expectation of altruism from others. Collectively, the studies suggest that simple reciprocal interactions are a potent trigger of altruism for young children, and that these interactions lead children to believe that their relationships are characterized by mutual care and commitment.

Monday, December 29, 2014

Exercise and intermittent fasting improve brain plasticity and health

I thought it might be useful to point to this brief review by Praag et al. that references several recent pieces of work presented at a recent Soc. for Neuroscience Meeting symposium. The experiments indicate that exercise and intermittent energy restriction/fasting may optimize brain function and forestall metabolic and neurodegenerative diseases by enhancing neurogenesis, synaptic plasticity and neuronal stress robustness.  (Motivated readers can obtain the article from me.) Here is their central summary figure:


Exercise and IER/fasting exert complex integrated adaptive responses in the brain and peripheral tissues involved in energy metabolism. As described in the text, both exercise and IER enhance neuroplasticity and resistance of the brain to injury and disease. Some of the effects of exercise and IER on peripheral organs are mediated by the brain, including increased parasympathetic regulation of heart rate and increased insulin sensitivity of liver and muscle cells. In turn, peripheral tissues may respond to exercise and IER by producing factors that bolster neuronal bioenergetics and brain function. Examples include the following: mobilization of fatty acids in adipose cells and production of ketone bodies in the liver; production of muscle-derived neuroactive factors, such as irisin; and production of as yet unidentified neuroprotective “preconditioning factors.” Suppression of local inflammation in tissues throughout the body and the nervous system likely contributes to prevention and reversal of many different chronic disease processes.

Friday, December 26, 2014

Several articles on aging brains.

Talking about aging brains is sort of a downer, but it's something I feel like I want to do as I trek onward with open eyes from my current age of 72 years. So, pointers to three recent articles on brain changes in aging:

Douaud et al. characterize a common brain network linking development, aging, and vulnerability to disease. They show that the idea of brain decline mirroring brain development is correct. Analysis of structural brain images reveals that a network of mainly higher-order regions that develop relatively late during adolescence demonstrate accelerated degeneration in old age.

And, from Salami et al.:
Aging is accompanied by disruptive alterations in large-scale brain systems, such as the default mode network (DMN) and the associated hippocampus (HC) subsystem, which support higher cognitive functions. However, the exact form of DMN–HC alterations and concomitant memory deficits is largely unknown. We identified age-related decrements in resting-state functional connectivity of the cortical DMN, whereas elevated connectivity between the bilateral HC was found along with attenuated HC–cortical connectivity. Critically, elevated HC at rest restricts the degree to which HC interacts with other brain regions during memory tasks, and thus results in memory deficits. This study provides empirical evidence of how the relationship between the DMN and HC breaks down in aging and how such alterations underlie deficient mnemonic processing.

Finally, Yotsumoto et al. find white matter in the older brain is more plastic than in the younger brain. Its changes during learning a visual perceptual task are not observed when younger subjects learn the same task.

Thursday, December 25, 2014

Exercise changes our muscle DNA

Following yesterday's post on changing gene expression with brain waves, I'll point to another bit of work on gene changing. Chemical changes to DNA, mainly methylation, can alter gene expression in response a number of environmental changes such as stress, diet, and pollutants. Reynolds points to work by Lindholm et al. now showing that exercise activates health enhancing genes by this epigenetic mechanism. They use the simple trick of measuring and comparing methylation of DNA in exercised and unexercised legs of single individuals (twentythree young subjects bicycled using only one leg, leaving the other unexercised, for three months. The pedaling was at a moderate pace for 45 min, four times per week for three months.) Not surprisingly, the exercised leg was more powerful, but in addition more than 5,000 sites on the genome of muscle cells from the exercised leg now featured new methylation patterns.

This work makes me wish I had a home kit for detecting methylation change in the DNA of my thumb muscles, which show dramatic changes in strength and size depending on how often and energetically I practice the piano.

Wednesday, December 24, 2014

A bit of science fiction...a brain implant that allows mind-controlled gene expression.

The experiments by Folcher et al. are done with optogenetic implants in mouse brains that are wirelessly controlled by human brain waves. This is the proof of concept step, preliminary to trying the implants in humans to control the expression of engineered light sensitive regulators of genes for therapeutic proteins. Here is their cartoon summary of the procedure:


The mind-controlled transgene expression device consisted of (a) an EEG headset that captured brain-wave activities (the encephalogram), identified mental state-specific electrical patterns (biofeedback, concentration, meditation) and processed discrete meditation-meter values (0–100; meditation-meter value plot), which were transmitted via Bluetooth to (b) the Arduino single-board microcontroller with a time-relay device and switching the (c) field generator ON and OFF. This BCI (a–c) controlled (d) the TC (c,d) of the field generator, which inductively coupled with the (d,e) receiver coil (RC) of the (e) wireless-powered optogenetic implant. (e) The NIR light LED illuminated the culture chamber of the wireless-powered optogenetic implant and programmed the designer cells to produce ​SEAP, which diffused through the semi-permeable membrane. The blood ​SEAP (human ​secreted alkaline phosphatase) levels of mice with subcutaneous wireless-powered optogenetic implants containing designer cells that were freely moving on the field generator could be modulated by the human subject’s mindset in a wireless, remote-controlled manner.

Tuesday, December 23, 2014

Impact of literacy on visual processing

From Pegado et al., a clear demonstration of how learning the act of reading enhances our visual processing:
How does learning to read affect visual processing? We addressed this issue by scanning adults who could not attend school during childhood and either remained illiterate or acquired partial literacy during adulthood (ex-illiterates). By recording event-related brain responses, we obtained a high-temporal resolution description of how illiterate and literate adults differ in terms of early visual responses. The results show that learning to read dramatically enhances the magnitude, precision, and invariance of early visual coding, within 200 ms of stimulus onset, and also enhances later neural activity. Literacy effects were found not only for the expected category of expertise (letter strings), but also extended to other visual stimuli, confirming the benefits of literacy on early visual processing.

Monday, December 22, 2014

Cross-species evidence that adaptive training diminishes distractibility in Aging.

Another fascinating study from Gazzaley's productive research group. A video clip is offered in the abstract. Here are the highlights and summary:

Highlights
•Adaptive distractor training selectively suppresses sensory distractor responses 
•Training enhances spectral and spatial tuning of sensory receptive fields in older rats 
•Top-down frontal theta is selectively restrained for distractors in trained humans 
•Training in older humans generalizes to enhanced aspects of cognitive control
Summary
Aging is associated with deficits in the ability to ignore distractions, which has not yet been remediated by any neurotherapeutic approach. Here, in parallel auditory experiments with older rats and humans, we evaluated a targeted cognitive training approach that adaptively manipulated distractor challenge. Training resulted in enhanced discrimination abilities in the setting of irrelevant information in both species that was driven by selectively diminished distraction-related errors. Neural responses to distractors in auditory cortex were selectively reduced in both species, mimicking the behavioral effects. Sensory receptive fields in trained rats exhibited improved spectral and spatial selectivity. Frontal theta measures of top-down engagement with distractors were selectively restrained in trained humans. Finally, training gains generalized to group and individual level benefits in aspects of working memory and sustained attention. Thus, we demonstrate converging cross-species evidence for training-induced selective plasticity of distractor processing at multiple neural scales, benefitting distractor suppression and cognitive control.

Friday, December 19, 2014

How to bridge the respective bubbles of our ideological tribes?

A number of recent mindblog posts have engaged the issue of the individual versus the collective good (for example, here, here, and here), a creative tension that has been central in human evolution. This has led me to mull a bit about the current apparent drift in the direction of more extreme individualism and rejection of the state’s concern for common interests.

I sometimes feel guilty for not being more evangelistic about promoting a rational scientific ideology that encompasses creationists, conservatives, and libertarians in a more broad evolutionary view, I wonder how it might be possible to induce these groups to admit a broader swath of reality than they currently seem willing to engage.

Concrete personal steps I might take? The expression of my ideas or those of others in writing is relatively easy, that is what this blog is about.

The problem is that MindBlog exists as one instance in the array of similarly minded sites that largely mirror each other’s views. I suspect that it is quite invisible to those following websites that deal with Creationism , conservatism, the libertarian or tea party movements that extoll individualism, etc. Those sites, in turn, are unlikely to be viewed by followers of atheist, agnostic, skeptic, or humanist sites more sympathetic to collective views of the individual in society.

I am a person who is timid about robust personal visceral engagement with those of opposing religious or political views, so I quail at the prospect of showing up at meetings of evangelical or ultra-conservative groups to ask questions like “you say you want the government off our backs...do you accept your social security or medicare payments? If so, do you see any inconsistency in your beliefs and actual practices?” Or, “You indicate you believe the biblical account that earth was created about 6,000 years ago. Do you accept the validity of the physical laws that permit your computer and iPhone to function? If so, how do you account for the fact that these same laws governing the physical properties of atoms prove that life on this planet began 3-4 billion years ago?”

I do hope that the a devout creationist or extreme individualist who occasionally stumbles on to a MindBlog post has his or her mental horizons slightly expanded.

Thursday, December 18, 2014

Critique of the Nature paper on dishonest bankers,

I wanted to pass on to MindBlog readers this item analyzing the paper noted in my recent post "Banking - a culture of dishonesty", Statistician Salil Mehta argues that the article is misleading, missing data, and mathematically inaccurate.

Several nuggets on the individual vs. the collective.

Following yesterday's post on the evolution of prosocial religions, I pass on a random set of links to articles also relevant to the individual and the collective.

Terrell notes that the current political schism between Republicans and Democrats has a foundation in different views about the whether an individual's primary purpose is to look out for communal or self interests.
...modern evolutionary research, anthropology, cognitive psychology and neuroscience have come down on the side of the philosophers who have argued that the basic unit of human social life is not and never has been the selfish, self-serving individual. Contrary to libertarian and Tea Party rhetoric, evolution has made us a powerfully social species, so much so that the essential precondition of human survival is and always has been the individual plus his or her relationships with others.
Luhrman does a piece "Wheat people versus rice people" which references the same work mentioned in MindBlog's May 21st post, and notes several other studies on individualistic versus collective cultures.

Rand et al. offer economic game experiments to illustrate how static network structure stabilizes human cooperation

Finally Crockett et al. do an experiment relevant to social cohesion, showing that harm to others outweighs harm to self in moral decision making - most people sacrifice more money to reduce a stranger’s pain than their own pain (the pain being delivered by electric shocks).

Wednesday, December 17, 2014

The Cultural Evolution of Prosocial Religions

Having been an author in an issue of "Behavioral and Brain Biology" published by Cambridge University Press, I receive notice of forthcoming articles inviting reviewers comments. The articles are then published with the reviewer's comments and authors' responses to the comments.

As a followup to my recent MindBlog post on E.O. Wilson's new book, I am passing on this interesting abstract of such a forthcoming article by Norenzayan et al.  (Motivated readers can email me if they wish to obtain a PDF of this article.)
We develop a cultural evolutionary theory of the origins of prosocial religions, and apply it to resolve two puzzles in human psychology and cultural history: 1) the rise of large-scale cooperation among strangers in the last twelve millennia, and 2) the spread of prosocial religions during the same period. We argue that these two developments were importantly linked. We explain how a package of culturally evolved religious beliefs and practices characterized by increasingly potent, moralizing supernatural agents, credible displays of faith, and other psychologically active elements conducive to social solidarity promoted internal harmony, large-scale cooperation, and high fertility, often leading to success in intergroup competition. In turn, prosocial religious beliefs and practices spread and aggregated as these successful groups expanded, or were copied by less successful groups. This synthesis is grounded in the idea that although religious beliefs and practices originally arose as non-adaptive byproducts of innate cognitive functions, particular cultural variants were then selected for their prosocial effects in a long-term cultural evolutionary process. This framework (1) reconciles key aspects of the adaptationist and byproduct approaches to the origins of religion, (2) explains a variety of empirical observations that have not received adequate attention, and (3) generates novel predictions. Converging lines of evidence drawn from diverse disciplines provide empirical support while at the same time encouraging new research directions and opening up new questions for exploration and debate.

Tuesday, December 16, 2014

The new surveillance state and our robotic future.

Isreal et al. examine one of the many uses to which individual credit scores are being put - to determine our cardiovascular risk (useful information for health insurance companies). They also note that credit scores are also used by employers, utility companies, and automobile insurers to index high-risk behavior; and by life insurance companies that incorporate credit scores into actuarial models.) Here is the abstract:
Credit scores are the most widely used instruments to assess whether or not a person is a financial risk. Credit scoring has been so successful that it has expanded beyond lending and into our everyday lives, even to inform how insurers evaluate our health. The pervasive application of credit scoring has outpaced knowledge about why credit scores are such useful indicators of individual behavior. Here we test if the same factors that lead to poor credit scores also lead to poor health. Following the Dunedin (New Zealand) Longitudinal Study cohort of 1,037 study members, we examined the association between credit scores and cardiovascular disease risk and the underlying factors that account for this association. We find that credit scores are negatively correlated with cardiovascular disease risk. Variation in household income was not sufficient to account for this association. Rather, individual differences in human capital factors—educational attainment, cognitive ability, and self-control—predicted both credit scores and cardiovascular disease risk and accounted for ∼45% of the correlation between credit scores and cardiovascular disease risk. Tracing human capital factors back to their childhood antecedents revealed that the characteristic attitudes, behaviors, and competencies children develop in their first decade of life account for a significant portion (∼22%) of the link between credit scores and cardiovascular disease risk at midlife. We discuss the implications of these findings for policy debates about data privacy, financial literacy, and early childhood interventions.
Also, the well known futuristic author Margaret Atwood offers an essay, well worth giving a read, on our growing efforts to craft a robotic future. One clip:
Why do we dream up such things? Because, deep down, we desire them...If we were technologically capable mice, we’d be perfecting deadly cat harpoons, or bird-exploding rockets, or cheese-on-demand molecular assemblers...To understand Homo sapiens’ primary wish list, go back to mythology. We endowed the gods with the abilities we wished we had ourselves: immortality and eternal youth, flight, resplendent beauty, total power, climate control, ultimate weapons, delicious banquets minus the cooking and washing up — and artificial creatures at our beck and call.
And just one more:
...people are dreaming up robotic prostitutes, complete with sanitary self-flushing features. Will there be a voice feature, and, if so, what will it say?...If the prospect of getting painfully stuck due to a malfunction keeps you from test-driving a full-body prostibot, you may soon be able to avail yourself of a remote kissing device that transmits the sensation of your sweetie’s kiss to your lips via haptic feedback and an apparatus that resembles a Silly Putty egg. (Just close your eyes.) Or you could venture all the way into the emerging world of “teledildonics” — essentially, remote-controlled vibrators. Push the game-controller levers, watch the effect on screen. Germ-free! Wait for Google or Skype to snatch this up.

Monday, December 15, 2014

Why elders smile, and wisdom in social signals.

Two articles relevant to becoming a senior person:
From Rijsbergen et al. (open access), a piece of work that reminds me of the book recently read by my book group here in Fort Lauderdale, the classic John Rechy novel about male hustlers, "City of Night", in which two age classes existed - 'young man' and 'old man.' Their abstract:
In an increasingly aging society, age has become a foundational dimension of social grouping broadly targeted by advertising and governmental policies. However, perception of old age induces mainly strong negative social biases. To characterize their cognitive and perceptual foundations, we modeled the mental representations of faces associated with three age groups (young age, middle age, and old age), in younger and older participants. We then validated the accuracy of each mental representation of age with independent validators. Using statistical image processing, we identified the features of mental representations that predict perceived age. Here, we show that whereas younger people mentally dichotomize aging into two groups, themselves (younger) and others (older), older participants faithfully represent the features of young age, middle age, and old age, with richer representations of all considered ages. Our results demonstrate that, contrary to popular public belief, older minds depict socially relevant information more accurately than their younger counterparts.
Also, David Brooks cites several books on the practical wisdom that comes with aging, and notes on the famous U-curve experiments in which people generally assess their own well being as high in their 20's and decreasing until about age 50 and then rising again until people rate themselve most happy at ages 82 to 85. A sample clip:
...experienced heads have intuitive awareness of the landscape of reality, a feel for what other people are thinking and feeling, an instinct for how events will flow. In “The Wisdom Paradox,” Elkhonon Goldberg details the many ways the brain deteriorates with age: brain cells die, mental operations slow. But a lifetime of intellectual effort can lead to empathy and pattern awareness. “What I have lost with age in my capacity for hard mental work,” Goldberg writes, “I seem to have gained in my capacity for instantaneous, almost unfairly easy insight.”

Friday, December 12, 2014

Physics, Emergence, and the Connectome - From the connectome to brain function

A special issue of Neuron on connectomics has a special open source section of articles with different views of the problems we face in relating details of brain structure to brain function. I would in particular recommend, Robert B. Laughlin's rather deep article on Physics, Emergence, and the Connectome, whose final paragraphs I copy in below:
It is not controversial that neurons do playful things. They deploy themselves somewhat haphazardly in glial matter, exhibiting no lateral crystalline order. They arborize with each other in ways that resemble tree branches and roots. They possess on-board memory that responds to incoming signals in an agent-based way and changes the signals they themselves generate.
What Might Be Missing
If we suspend disbelief for a moment and consider the possibility that play might be a design principle rather than a higher emergent phenomenon, a simple idea presents itself as to why making sense of the connectome might be so difficult. The latter includes things like obtaining the entire map of C. elegans and finding that it still doesn’t make any sense, and that it even has no action potentials. It is a small step from systems that play without direction to systems that play with rules, and from there to systems that play games with each other. Were that to happen, it could easily account for something as complicated as the brain, for it is well known from the study of automata that simple systems playing games can create enormously complex structures with very sophisticated functions. It is also known that small changes in the rule base can make enormous changes in the structures that develop. There is also the obvious example of the human economy, a thing that grows out of simple rules of money exchange that transcends anyone’s attempt to understand and manage it. One of the economy’s physical manifestations is a great network of highways with mighty cities at its hubs. It would obviously be a fool’s errand to try understanding the economy by mapping its roads.
There is nothing supernatural or unscientific in the concept of gaming making a brain, or for that matter an entire organism. All that is required is an intermediate stage of organization that is unstable, like the weather. Physical science tells us that unstable development can be perfectly deterministic yet difficult, if not impossible, to follow by experiment, among other reasons because unstable evolution is functionally the same thing as cryptography. Thus the scientific resolution of the whole mystery might simply be that the genome instructs the system to go wild and generate a bag of tools and parts it might need to construct something interesting, and then sends a subsequent instruction to go out and play. Emergent self-organization then finishes the job.

Thursday, December 11, 2014

Psilocybin changes brain connectivity.

Petri et al. show that "the brain's functional patterns undergoes a dramatic change post-psilocybin, characterized by the appearance of many transient structures of low stability and of a small number of persistent ones that are not observed in the case of placebo." A simple reading of their results is that the effect of psilocybin is to relax constraints on brain function, ascribing cognition a more flexible quality. This may account for the transient synesthesia reported by many with psilocybin, hearing colors or seeing sounds.


Simplified visualization of the persistence homological scaffolds. a.) placebo baseline b.) with psilocybin
A review of the work by Bone notes:
When ingested, psilocybin metabolizes to psilocin, which resembles the chemical structure of serotonin — a neurotransmitter that regulates mood, appetite, sleep, cognitive functions like memory and learning and feelings of pleasure. Psilocin may simulate serotonin, and stimulate serotonin receptors in the brain...psilocybin therapy could be useful in treating disorders like depression, in which people get stuck in a spiral of negative thoughts. Like electric shock therapy, psilocybin might act like tripping a circuit breaker or rebooting your computer.
The Bone review also give links to studies on psilocybin effects on other psychological syndromes.

Wednesday, December 10, 2014

We search for meaning at the start of each chronological decade.

Recent soulful introspection by my husband, who moves from age 59 to 60 in late December, motivates me to point to this study by Alter and Hershfield, who perform six cross cultural studies to show the same thing I recall from my own experience when I was 49, 59 and 69: that people renew their search for meaning as they face a new decade. The studies aggregated data available on several major survey data websites relevant to values, search for meaning, extramarital affairs, suicide rates, and marathon sign-ups and performance. The summary from their significance and abstract sections:
...people audit the meaningfulness of their lives as they approach a new decade in chronological age, further suggesting that people across dozens of countries and cultures are prone to making significant decisions as they approach each new decade...Six studies show that adults undertake a search for existential meaning when they approach a new decade in age (e.g., at ages 29, 39, 49, etc.) or imagine entering a new epoch, which leads them to behave in ways that suggest an ongoing or failed search for meaning (e.g., by exercising more vigorously, seeking extramarital affairs, or choosing to end their lives).

Tuesday, December 09, 2014

Banking - a culture of dishonesty

Kelland points to work by Cohn et al., who have studied bank workers and other professionals in experiments in which they won more money if they cheated. They found that bankers were more dishonest when they were made particularly aware of their professional role. Employees in other sectors - manufacturing, telecoms, pharmaceuticals - did not show more dishonest behavior when their professional identity or banking-related information was emphasized. Honesty was tested by having participants toss a coin 10 times, unobserved, and report the results, knowing whether heads or tails would yield a $20 reward. They were told they could keep their winnings if they were more than or equal to those of a randomly selected subject from a pilot study. The control group reported ~50% winning tosses, and bankers who banking identity had been emphasized to them reported ~58% as wins. The authors conclude that the prevailing business culture in the banking industry weakens and undermines the honesty norm, suggesting a need for measures that re-establish an honest culture.