Fool the brain to enhance performance with a carbohydrate rinse

Kolata reports on exercise physiologists stumbling on an unexpected feature: simply rinsing the mouth with a carbohydrate solution stimulates receptors that report to the brain, causing it to instruct increased intensity and duration of effort in anticipation of an imminent food reward.

Our dread of idleness

Being a hyper-purposeful person myself, I've always been attracted to the opposite pole represented by The Idler,  both the original book and the subsequent magazine whose intention is "to return dignity to the art of loafing, to make idling into something to aspire towards rather than reject."  Thus I thought this piece by Hsee et al. worth passing on. They set up experiments in which people who voluntarily choose busyness report being happier than those who voluntarily choose idleness. Further, people who are forced into busyness report being happier than those who are forced into idleness. People choose to be idle if they do not have reason to be busy, but that even a specious justification can prompt them to seek busyness.  Here is their abstract:

There are many apparent reasons why people engage in activity, such as to earn money, to become famous, or to advance science. In this report, however, we suggest a potentially deeper reason: People dread idleness, yet they need a reason to be busy. Accordingly, we show in two experiments that without a justification, people choose to be idle; that even a specious justification can motivate people to be busy; and that people who are busy are happier than people who are idle. Curiously, this last effect is true even if people are forced to be busy. Our research suggests that many purported goals that people pursue may be merely justifications to keep themselves busy.

Their (slightly edited) speculations are interesting to read:

We speculate that the concurrent desires for busyness and for justification are rooted in evolution. In their strife for survival, human ancestors had to conserve energy to compete for scarce resources; expending energy without purpose could have jeopardized survival. With modern means of production, however, most people today no longer expend much energy on basic survival needs, so they have excessive energy, which they like to release through action. Yet the long-formed tendency to conserve energy lingers, making people wary of expending effort without purpose.

Our research also complements recent research of Airely et al.  that suggests that people work in order to search for meaning (i.e., achievement and recognition), our study suggests that people search for meaning in order to work. In Greek mythology, Sisyphus’ punishment, imposed by Zeus, was to eternally roll a rock toward the top of a hill, never to arrive there. The research of Ariely et al. predicts that Sisyphus would have been happier if Zeus had allowed the rock to reach the top of the hill and had then recognized Sisyphus’ achievement. Our research suggests that Sisyphus was better off with his punishment than he would have been with a punishment of an eternity of doing nothing, and that he might have chosen rolling a rock over idleness if he had been given a slight reason for doing it.

Idleness is potentially malignant. If idle people remain idle, they are miserable. If idle people become busy, they will be happier, but the outcome may or may not be desirable, depending on the value of the chosen activity. Busyness can be either constructive or destructive. Ideally, idle people should devote their energy to constructive courses, but it is often difficult to predict which actions are constructive (e.g., are business investments or scientific discoveries always constructive?), and not every idle individual is capable of constructive contributions. Idle people often engage in destructive busyness (from inner-city crimes to cross-border wars); as Hippocrates observed in Decorum, “Idleness and lack of occupation tend―nay are dragged―towards evil.”

We advocate a third kind of busyness: futile busyness, namely, busyness serving no purpose other than to prevent idleness. Such activity is more realistic than constructive busyness and less evil than destructive busyness. However, as we demonstrated in the no-justification (same-candy or same-design) condition of our research, most people will not voluntarily choose futile busyness.

This is where paternalism can play a role. For example, homeowners may increase the happiness of their idle housekeepers by letting in some mice and prompting the housekeepers to clean up. Governments may increase the happiness of idle citizens by having them build bridges that are actually useless. Indeed, some such interventions already exist: Airports have tried to increase the happiness (or reduce the unhappiness) of passengers waiting at the baggage carousel by increasing the distance between the gate and the baggage claim area, forcing them to walk far rather than wait idly. Similar intentions may be applied at the societal level. Although these strategies may not be ethical, we believe that futile busyness trumps both idleness and destructive busyness.

Mindblog on the road

I'm in Ft. Lauderdale today through next Tuesday, attending the 85th birthday party/piano concert David Goldberger, the fellow I did a four-hands concert with last March. This may have an effect on the frequency of next week's posts.

Acetaminophen (tylenol) reduces physical and social pain.

DeWall et al. show that an anti-pain medication that acts on the brain's pain pathways, reduces both physical and social pain:

Pain, whether caused by physical injury or social rejection, is an inevitable part of life. These two types of pain—physical and social—may rely on some of the same behavioral and neural mechanisms that register pain-related affect. To the extent that these pain processes overlap, acetaminophen, a physical pain suppressant that acts through central (rather than peripheral) neural mechanisms, may also reduce behavioral and neural responses to social rejection. In two experiments, participants took acetaminophen or placebo daily for 3 weeks. Doses of acetaminophen reduced reports of social pain on a daily basis. We used functional magnetic resonance imaging to measure participants’ brain activity, and found that acetaminophen reduced neural responses to social rejection in brain regions previously associated with distress caused by social pain and the affective component of physical pain (dorsal anterior cingulate cortex, anterior insula). Thus, acetaminophen reduces behavioral and neural responses associated with the pain of social rejection, demonstrating substantial overlap between social and physical pain.

A growing isolated brain can organize itself.

How much of the development of our brain's cortex depends on it being able to talk with other parts of the brain and body? Apparently, not as much as had been thought. Zhou et al. have used a mouse mutant in which the neocortex had been disconnected from the rest of the brain in order to analyze the development of the surface map (which might be compared to a geopolitical map supported by an infrastructure of shipping, communication, and regulatory networks). In normal mice, a few weeks of postnatal development complete the brain's organization; the mutant mice survive during this phase but die at about 3 weeks of age. During these weeks, the mutant mice, despite having disconnected brains, display a variety of behaviors: eating, drinking, walking, and swimming. Thus, "protomap" formation, namely cortical lamination and formation of areas, proceed normally in absence of extrinsic connections, but survival of projection neurons and acquisition of mature morphological and some electrophysiological features depend on the establishment of normal cortical–subcortical relationships.

Dopamine, Time, and Our Impulsivity

Yet another fascinating piece of work from the group around Ray Dolan at the London Wellcome Trust Center for Neuroimaging. They show that enhancing dopamine activity can increase our propensity to choose smaller–sooner over larger–later rewards:

Disordered dopamine neurotransmission is implicated in mediating impulsiveness across a range of behaviors and disorders including addiction, compulsive gambling, attention-deficit/hyperactivity disorder, and dopamine dysregulation syndrome. Whereas existing theories of dopamine function highlight mechanisms based on aberrant reward learning or behavioral disinhibition, they do not offer an adequate account of the pathological hypersensitivity to temporal delay that forms a crucial behavioral phenotype seen in these disorders. Here we provide evidence that a role for dopamine in controlling the relationship between the timing of future rewards and their subjective value can bridge this explanatory gap. Using an intertemporal choice task, we demonstrate that pharmacologically enhancing dopamine activity increases impulsivity by enhancing the diminutive influence of increasing delay on reward value (temporal discounting) and its corresponding neural representation in the striatum. This leads to a state of excessive discounting of temporally distant, relative to sooner, rewards. Thus our findings reveal a novel mechanism by which dopamine influences human decision-making that can account for behavioral aberrations associated with a hyperfunctioning dopamine system.

Motivating only half our bodies.

Schmidt et al. do a simple experiment to show that motivation need not be a person-level concept, our left and right hemispheres can be separately motivated:

Motivation is generally understood to denote the strength of a person’s desire to attain a goal. Here we challenge this view of motivation as a person-level concept, in a study that targeted subliminal incentives to only one half of the human brain. Participants in the study squeezed a handgrip to win the greatest fraction possible of each subliminal incentive, which materialized as a coin image flashed in one visual hemifield. Motivation effects (i.e., more force exerted when the incentive was higher) were observed only for the hand controlled by the stimulated brain hemisphere. These results show that in the absence of conscious control, one brain hemisphere, and hence one side of the body, can be motivated independently of the other.

The mind is the body - tumor suppression by enriched environment

An amazing article by Cao et al. brings home the intimate attachment between mental well-being and health - in mice (and by implication, for us too).   An enriched environment promotes formation of a nerve growth factor which in turn inhibits tumor growth through a series of biochemical steps, shown in the summary graphic before the abstract. A commentary by Jonah Lehrer notes that we need "a new metaphor for the interactions of the brain and body. They aren't simply connected via some pipes and tubes. They are emulsified together, so hopelessly intertwined that everything that happens in one affects the other. Holism is the rule."

Cancer is influenced by its microenvironment, yet broader, environmental effects also play a role but remain poorly defined. We report here that mice living in an enriched housing environment show reduced tumor growth and increased remission. We found this effect in melanoma and colon cancer models, and that it was not caused by physical activity alone. Serum from animals held in an enriched environment (EE) inhibited cancer proliferation in vitro and was markedly lower in leptin. Hypothalamic brain-derived neurotrophic factor (BDNF) was selectively upregulated by EE, and its genetic overexpression reduced tumor burden, whereas BDNF knockdown blocked the effect of EE. Mechanistically, we show that hypothalamic BDNF downregulated leptin production in adipocytes via sympathoneural β-adrenergic signaling. These results suggest that genetic or environmental activation of this BDNF/leptin axis may have therapeutic significance for cancer.

How superstition improves performance

Interesting stuff from Damish et al. They demonstrate a causal effect of an activated good-luck-associated superstition on subsequent performance (using things like 'lucky charms'). Participants for whom a superstition was activated performed better in various motor and cognitive tasks compared with participants for whom no such concept was activated. Second, they showed that these performance-enhancing effects are mediated by an increase in perceived level of self-efficacy. Activating a good-luck superstition leads to improved performance by boosting people’s belief in their ability to master a task. Here is their abstract:

Superstitions are typically seen as inconsequential creations of irrational minds. Nevertheless, many people rely on superstitious thoughts and practices in their daily routines in order to gain good luck. To date, little is known about the consequences and potential benefits of such superstitions. The present research closes this gap by demonstrating performance benefits of superstitions and identifying their underlying psychological mechanisms. Specifically, four different experiments show that activating good-luck-related superstitions via a common saying or action (e.g., “break a leg,” keeping one’s fingers crossed) or a lucky charm improves subsequent performance in golfing, motor dexterity, memory, and anagram games. Furthermore, they demonstrate that these performance benefits are produced by changes in perceived self-efficacy. Activating a superstition boosts participants’ confidence in mastering upcoming tasks, which in turn improves performance. Finally, they show that increased task persistence constitutes one means by which self-efficacy, enhanced by superstition, improves performance.

Behavioral economics as a palliative cop-out

Loewenstein and Ubel make some very simple and compelling points in their article on the use of behavioral economics to guide public policy and nudge people's behavior in desired directions. They note that behavioral economics is being used as a political expedient, allowing policymakers to avoid painful but more effective solutions rooted in traditional economics:

Take, for example, our nation’s obesity epidemic. The fashionable response, based on the belief that better information can lead to better behavior, is to influence consumers through things like calorie labeling — for instance, there’s a mandate in the health care reform act requiring restaurant chains to post the number of calories in their dishes...But studies of New York City’s attempt at calorie posting have found that it has had little impact on dieters’ choices...Obesity isn’t a result of a lack of information; instead, economists argue that rising levels of obesity can be traced to falling food prices, especially for unhealthy processed foods...To combat the epidemic effectively, then, we need to change the relative price of healthful and unhealthful food — for example, we need to stop subsidizing corn, thereby raising the price of high fructose corn syrup used in sodas, and we also need to consider taxes on unhealthful foods. But because we lack the political will to change the price of junk food, we focus on consumer behavior.

A “gallons-per-mile” bill recently passed by the New York State Senate is intended to help drivers think more clearly about the fuel consumption of the vehicles they purchase; research has shown that gallons-per-mile is a more effective means of getting drivers to appreciate the realities of fuel consumption than the traditional miles-per-gallon...But more and better information fails to get at the core of the problem: people drive large, energy-inefficient cars because gas is still relatively cheap. An increase in the gas tax that made the price of gas reflect its true costs would be a far more effective — though much more politically painful — way to reduce fuel consumption.

Thriving on selfishness

I enjoyed Marina Krakovsky's article in the April Scientific American on Omar Tonsi Eldakar's game theoretical take on why it pays for cheaters to punish other cheaters in maintaining the best balance between altruistic cooperators and defectors:

It’s the altruism paradox: If everyone in a group helps fellow members, everyone is better off—yet as more work selflessly for the common good, cheating becomes tempting, because individuals can enjoy more personal gain if they do not chip in. But as freeloaders exploit the do-gooders, everybody’s payoff from altruism shrinks.

All kinds of social creatures, from humans down to insects and germs, must cope with this problem; if they do not, cheaters take over and leech the group to death. So how does altruism flourish? Two answers have predominated over the years: kin selection, which explains altruism toward genetic relatives—and reciprocity—the tendency to help those who have helped us. Adding to these solutions, evolutionary biologist Omar Tonsi Eldakar came up with a clever new one: cheaters help to sustain altruism by punishing other cheaters, a strategy called selfish punishment.

“All the theories addressed how altruists keep the selfish guys out,” explains Eldakar, who described his model with his Ph.D. thesis adviser David Sloan Wilson of Binghamton University in May 2008. Because selfishness undermines altruism, altruists certainly have an incentive to punish cheaters—a widespread behavior pattern known as altruistic punishment. But cheaters, Eldakar realized, also have reason to punish cheaters, only for motives of their own: a group with too many cheaters does not have enough altruists to exploit. As Eldakar puts it, “If you’re a single selfish individual in a group of altruists, the best thing you can do evolutionarily is to make sure nobody else becomes selfish—make sure you’re the only one.” That is why, he points out, some of the harshest critics of sports doping, for example, turn out to be guilty of steroid use themselves: cheating gives athletes an edge only if their competitors aren’t doing it, too.

Although it is hypocritical for cheaters to punish other cheaters, members of the group do not balk as long as they benefit. And when selfish punishment works well, benefit they do. In a colony of tree wasps (where workers care for the queen’s offspring instead of laying their own eggs), a special caste of wasps sting other worker wasps that try to lay eggs, even as the vigilante wasps get away with laying eggs themselves. In a strange but mutually beneficial bargain, punishing other cheaters earns punishers the right to cheat.

In the year since Eldakar and Wilson wrote up their analysis, their insights have remained largely under the radar. But the idea of a division of labor between cooperators and policing defectors appeals to Pete Richerson, who studies the evolution of cooperation at the University of California, Davis. “It’s nothing as complicated as a salary, but allowing the punishers to defect in effect does compensate them for their services in punishing other defectors who don’t punish,” he says. After all, policing often takes effort and personal risk, and not all altruists are willing to bear those costs.

Corrupt policing may evoke images of the mafia, and indeed Eldakar notes that when the mob monopolizes crime in a neighborhood, the community is essentially paying for protection from rival gangs—a deal that, done right, lowers crime and increases prosperity. But mob dynamics are not always so benign, as the history of organized crime reveals. “What starts out as a bunch of goons with guns willing to punish people [for breaching contracts] becomes a protection racket,” Richerson says. The next question, therefore, is, What keeps the selfish punishers themselves from overexploiting the group?

Wilson readily acknowledges this limitation of the selfish punishment model. Although selfish punishers allow cooperators to gain a foothold within a group, thus creating a mix of cheaters and cooperators, “there’s nothing telling us that that mix is an optimal mix,” he explains. The answer to that problem, he says, is competition not between individuals in a group but between groups. That is because whereas selfishness beats altruism within groups, altruistic groups are more likely to survive than selfish groups. So although selfish punishment aids altruism from within a group, the model also bolsters the idea of group selection, a concept that has seen cycles of popularity in evolutionary biology.

What is more, altruism sometimes evolves without selfish punishment. In a software simulation, Eldakar and Wilson have found that as the cost of punishing cheaters falls, so do the number of selfish punishers. “When punishment is cheap, lots of people punish,” Wilson explains. And among humans, there is no shortage of low-cost ways to keep others in line—from outright ostracism to good old-fashioned gossip.

Moral evaluations influence our mental state ascriptions.

Gilbert Chin, in the "Editor's Choice" section of Science, gives a nice summary of work by Uttich and Lombrozo in their Cognition article:

A robust phenomenon established empirically during the past decade is the tendency of observers to regard morally bad consequences (such as harm to the environment) that occur as a secondary effect of actions taken by an agent (such as a corporate CEO) in the course of achieving the primary effect—an increase in revenue—as having been committed intentionally. In contrast, morally good consequences in a similar scenario are judged as being incidental. A number of explanations for this asymmetry (also known as the Knobe effect) have been put forth; most prominent, perhaps, is the proposal that the moral valence of the side effect alters the observer's inference about the agent's mental state; that is, whether the CEO acted with intent. Uttich and Lombrozo bring to bear a series of vignettes in which the type of social norm (moral versus conventional), the kind of behavior (norm-conforming versus norm-violating), and the outcome valence (helpful versus harmful) were varied independently. Their results support a "rational scientist" framework, so that the observer's computation of the agent's state of mind weights actions that flout commonly accepted rules of behavior as being more informative and hence diagnostic of intentionality than conformist ones.

Here is the abstract from the article:

Theory of mind, the capacity to understand and ascribe mental states, has traditionally been conceptualized as analogous to a scientific theory. However, recent work in philosophy and psychology has documented a “side-effect effect” suggesting that moral evaluations influence mental state ascriptions, and in particular whether a behavior is described as having been performed ‘intentionally.’ This evidence challenges the idea that theory of mind is analogous to scientific psychology in serving the function of predicting and explaining, rather than evaluating, behavior. In three experiments, we demonstrate that moral evaluations do inform ascriptions of intentional action, but that this relationship arises because behavior that conforms to norms (moral or otherwise) is less informative about underlying mental states than is behavior that violates norms. This analysis preserves the traditional understanding of theory of mind as a tool for predicting and explaining behavior, but also suggests the importance of normative considerations in social cognition.

How exercise stimulates brain nerve cell growth

Human and animal brains produce new brain cells (neurogenesis), and exercise increases this process. Gretchen Reynolds reviews work of Cage and others suggesting a mechanism for how this works: exercise lowers the levels of a protein (BMP, or bone morphogenetic protein) that suppresses nerve cell division in the hippocampus. 

Factoids about aging, reaching 70

Studies suggest that aging brings a more settled and calm view of what one is, and what one is not, and a general increase in contentment. They also point to the sobering point that attentional and executive functions of one's brain apparently move (retreat) to more frontal brain structures, perhaps reflecting the increased effort and focus being required to hold things together, leaving behind fading richer and younger limbic and lower brain autopilots that once were more open to, and could juggle with, many novel contexts and feelings.

Just to keep current my list of the general litany of degenerative changes that can be observed on aging (present company excepted, of course), I thought I would point to this article from this past Sunday's NYTimes.   Kate Zernike writes about turning 70, a recent transition for Ringo Starr who gave himself a 70th birthday concert at Radio City Music Hall (it happens to me in two years).   I was most fascinated (and sobered) by what entering the +70 club gets you. I've rearranged part of their graphic to summarize some of the numbers:

A sinister bias in calling football (soccer) fouls

I came across this interesting bit from Kranjec et al. just after watching the football world cup game (Spain vs. the Netherlands) with my family and friends this past sunday.  The authors suggest that a perceptual bias associated with left to right reading might predispose referees to call fouls more frequently for right to left moving events than for right to left moving events.  Thus referees standing across from each other might call a play differently.

Distinguishing between a fair and unfair tackle in soccer can be difficult. For referees, choosing to call a foul often requires a decision despite some level of ambiguity. We were interested in whether a well documented perceptual-motor bias associated with reading direction influenced foul judgments. Prior studies have shown that readers of left-to-right languages tend to think of prototypical events as unfolding concordantly, from left-to-right in space. It follows that events moving from right-to-left should be perceived as atypical and relatively debased. In an experiment using a go/no-go task and photographs taken from real games, participants made more foul calls for pictures depicting left-moving events compared to pictures depicting right-moving events. These data suggest that two referees watching the same play from distinct vantage points may be differentially predisposed to call a foul.

The benefits of 'losing it'

Benedict Carey does an interesting article on the personal and social utility of letting out, expressing, strong spontaneous emotional reactions.   President Obama's failure to do this has led people to question his sincerity or commitment to fixing financial institutions or oil spills. This is line with Pinker's argument that emotions evolved as guarantors or our authenticity.  Such authenticity is the issue in Obama's failure to emote. A few clips:

...people develop a variety of psychological tools to manage what they express in social situations, and those techniques often become subconscious, affecting interactions in unintended ways. The better that people understand their own patterns, the more likely they are to see why some emotionally charged interactions go awry — whether from too little control or, in the president’s case, perhaps too much.

Psychologists divide regulation strategies into two broad categories: pre-emptive, occurring before an emotion is fully felt; and responsive, coming afterward... Suppression, while clearly valuable in some situations (no laughing at funerals, please), has social costs that are all too familiar to those who know its cold touch.

Pre-emptive techniques can work in more subtle ways. One of these is simple diversion, reflexively focusing on the good and ignoring the bad — rereading the praise in an evaluation and ignoring or dismissing any criticism. A 2009 study...found that people over 55 were much more likely than those aged 25 and under to focus on positive images when in a bad mood — thereby buoying their spirits. The younger group was more likely to focus on negative images when feeling angry or down... older people were twice as likely as younger ones to be “rapid regulators” — people whose mood bounced back quickly, sometimes within minutes, after ruminating on depressing memories...older people tend to regulate their emotions faster, and are not as motivated to explore negative information, to engage negative images, as younger people are...And it makes some sense that younger adults would explore the negative side of things, that they need to and maybe want to experience them to experience life as they develop their own strategies to regulate...the ability to shrug off feelings of disgust or outrage may suit an older group but strike younger people as inauthentic, even callous.

Music sightreading skill - practice doesn't make perfect

I have an ability to sightread extremely complicated and difficult music, a fact noted by my first piano teacher after my initial lesson when I was six years old. It seems obvious to me that I came wired that way, practice had very little to do with it. This attitude, which conflicts with the general view that expertise is due mainly to diligent and repetitive practice of a skill, is confirmed by recent observations of Meinz and Hambrick:

Deliberate practice—that is, engagement in activities specifically designed to improve performance in a domain—is strongly predictive of performance in domains such as music and sports. It has even been suggested that deliberate practice is sufficient to account for expert performance. Less clear is whether basic abilities, such as working memory capacity (WMC), add to the prediction of expert performance, above and beyond deliberate practice. In evaluating participants having a wide range of piano-playing skill (novice to expert), we found that deliberate practice accounted for nearly half of the total variance in piano sight-reading performance. However, there was an incremental positive effect of WMC, and there was no evidence that deliberate practice reduced this effect. Evidence indicates that WMC is highly general, stable, and heritable, and thus our results call into question the view that expert performance is solely a reflection of deliberate practice.

Goal pursuit outside our conscious awareness

Custer and Aarts expand on a favorite topic of mine (see the "I-Illusion" podcast in the left column): how our sense of authorship and agency is an illusion. They review research demonstrating that goals and the motivation to pursue them can arise unconsciously, and propose a mechanism for how this may happen. Here is a mix of their abstract, text clips, and a proposed mechanism:

People often act in order to realize desired outcomes, or goals. Although behavioral science recognizes that people can skillfully pursue goals without consciously attending to their behavior once these goals are set, conscious will is considered to be the starting point of goal pursuit. Indeed, when we decide to work hard on a task, it feels as if that conscious decision is the first and foremost cause of our behavior. That is, we are likely to say, if asked, that the decision to act produced the actions themselves. Recent discoveries, however, challenge this causal status of conscious will. They demonstrate that goals themselves can arise and operate unconsciously - actions are initiated even though we are unconscious of the goals to be attained or their motivating effect on our behavior. Social situations and stimuli in the surroundings activate or prime goals in our minds outside of our awareness, thereby motivating and guiding us.

Figure - The proposed mechanism for unconscious goal pursuit.

Experiments compatible with this model:

Neuroimaging research has discovered that reward cues are processed by limbic structures such as the nucleus accumbens and the ventral striatum. These subcortical areas play a central role in determining the rewarding value of outcomes and are connected to frontal areas in the cortex that facilitate goal pursuit. These reward centers in the brain respond to evolutionarily relevant rewards such as food and sexual stimuli, but also to learned rewards (such as money or status), or words (such as good or nice) that are associated with praise or rewards. This demonstrates that regardless of their shape or form, such positive stimuli induce a reward signal that is readily picked up by the brain.

Other recent research has demonstrated that subliminal primes that are specifically related to rewards can motivate people to increase the effort they invest in behaviors. In one study, participants could earn money by squeezing a handgrip. Before each squeeze, the money that could be earned was indicated by a 1-pound or 1-penny coin on the screen. Whereas on some trials the coin was clearly visible, on others it was presented subliminally. Thus, effects of conscious and unconscious reward cues could be compared within one experiment. It was found that people squeezed harder on high than on low reward trials, regardless of whether the reward was consciously visible or not. Moreover, this effect was accompanied by activation in the brain areas that play a role in reward processing and the recruitment of effort for action…These findings indicate that conscious and unconscious reward cues have similar effects on effort and flexible cognitive processing, which suggests that conscious awareness of rewards is not needed for goal pursuit to occur.

A smooth botox face inhibits emotion processing

Richie Davidson and collaborators at Wisconsin come up with this interesting gem, on the consequences of a face made more smooth and beautiful by Botulinum toxin injections:

How does language reliably evoke emotion, as it does when people read a favorite novel or listen to a skilled orator? Recent evidence suggests that comprehension involves a mental simulation of sentence content that calls on the same neural systems used in literal action, perception, and emotion. In this study, we demonstrated that involuntary facial expression plays a causal role in the processing of emotional language. Subcutaneous injections of botulinum toxin-A (BTX) were used to temporarily paralyze the facial muscle used in frowning. We found that BTX selectively slowed the reading of sentences that described situations that normally require the paralyzed muscle for expressing the emotions evoked by the sentences. This finding demonstrates that peripheral feedback plays a role in language processing, supports facial-feedback theories of emotional cognition, and raises questions about the effects of BTX on cognition and emotional reactivity. We account for the role of facial feedback in language processing by considering neurophysiological mechanisms and reinforcement-learning theory.

The reading module of our brains.

I’ve been meaning to mention an excellent article by Oliver Sachs in the June 28 issue of The New Yorker “A man of letters”. It describes a class of stroke patients who selectively loose the ability to read letters, frequently seeing them as some kind of foreign gibberish, yet can still write (“alexia sine agraphia”). In this article, unlike some of his others which have frustrated me by not getting down to the brain basics, he give an excellent summary of how it is that our brains come to have a specialized module for a skilled activity that was invented only ~5,000 years ago, less than an eye blink in evolutionary time. Here is my editing of chunks that give the bottom line:

There may be objects that are recognized at birth, such as faces, but beyond this the world of objects must be learned through experience and activity: looking, touching, handling, correlating the feel of objects with their appearance...Visual object recognition depends on the inferotemporal cortex..where neuronal function is very plastic...Mark Changizi and colleagues at Caltech, from examining more than a hundred ancient and modern writing systems, have shown that all of them, while geometrically very different, share certain basic topological similarities...which resemble topological invariants in a range of natural settings, leading them to hypothesize that the shapes of letters "have been selected to resemble the conglomeration of contours found in natural scenes, thereby tapping into our already-existing object recognition mechanisms."

The origin of writing and reading cannot be understood as a direct evolutionary adaptation. It is dependent on the plasticity of the brain, and on the fact that, even within the small span of a human lifetime, experience - experiential selection - is as powerful an agent of change as natural selection... We are literate not by virtue of a divine intervention (which Alfred Russel Wallace proposed, contra Darwin) but through a cultural invention and a cultural selection that make a brilliant and creative new use of a preexisting neural proclivity.