Sense of justice discovered in the brain

[abdulhakeem]

October 2006
Helen Phillips

A brain region that curbs our natural self interest has been identified. The studies could explain how we control fairness in our society, researchers say.

Humans are the only animals to act spitefully or to mete out "justice", dishing out punishment to people seen to be behaving unfairly – even if it is not in the punisher's own best interests. This tendency has been hard to explain in evolutionary terms, because it has no obvious reproductive advantage and punishing unfairness can actually lead to the punisher being harmed.

Now, using a tool called the “ultimatum game”, researchers have identified the part of the brain responsible for punishing unfairness. Subjects were put into anonymous pairs, and one person in each pair was given $20 and asked to share it with the other. They could choose to offer any amount – if the second partner accepted it, they both got to keep their share.

In purely economic terms, the second partner should never reject an offer, even a really low one, such as $1, as they are still $1 better off than if they rejected it. Most people offered half of the money. But in cases where only a very small share was offered, the vast majority of "receivers" spitefully rejected the offer, ensuring that neither partner got paid.

Fehr's fair

Previous brain imaging studies have revealed that part of the frontal lobes known as the dorsolateral prefrontal cortex, or DLPFC, becomes active when people face an unfair offer and have to decide what to do. Researchers had suggested this was because the region somehow suppresses our judgement of fairness.

But now, Ernst Fehr, an economist at the University of Zurich, and colleagues have come to the opposite conclusion – that the region suppresses our natural tendency to act in our own self interest.

They used a burst of magnetic pulses called transcranial magnetic stimulation (TMS) – produced by coils held over the scalp – to temporarily shut off activity in the DLPFC. Now, when faced with the opportunity to spitefully reject a cheeky low cash offer, subjects were actually more likely to take the money.

The researchers found that the DLPFC region's activity on the right side of the brain, but not the left, is vital for people to be able to dish out such punishment.

"The DLPFC is really causal in this decision. Its activity is crucial for overriding self interest," says Fehr. When the region is not working, people still know the offer is unfair, he says, but they do not act to punish the unfairness.

Moral centre?

"Self interest is one important motive in every human," says Fehr, "but there are also fairness concerns in most people."

"In other words, this is the part of the brain dealing with morality," says Herb Gintis, an economist at the University of Massachusetts in Amherst, US. " is involved in comparing the costs and benefits of the material in terms of its fairness. It represses the basic instincts."

Psychologist Laurie Santos, at Yale University in Connecticut, US, comments: "This form of spite is a bit of an evolutionary puzzle. There are few examples in the animal kingdom." The new finding is really exciting, Santos says, as the DLPFC brain area is expanded only in humans, and it could explain why this type of behaviour exists only in humans.

Fehr says the research has interesting implications for how we treat young offenders. "This region of the brain matures last, so if it is truly overriding our own self interest then adolescents are less endowed to comply with social norms than adults," he suggests. The criminal justice system takes into account differences for under-16s or under-18s, but this area fully matures around the age of 20 or 22, he says.

Journal reference: [I]Science (DOI: 10.1126/science.1129156)

http://www.newscientist.com/article/dn10239-sense-of-justice-discovered-in-the-brain.html

[abdulhakeem]

Why say no to free money? It's neuro-economics, stupid

October 07, 2006
By Mark Henderson

Studies show how the brain lets the emotions override common sense when reaching some tough decisions. Our correspondent reports on the 'ultimatum game'

IMAGINE that you are sitting next to a complete stranger who has been given £10 to share between the two of you. He must choose how much to keep for himself and how much to give to you.

He can be as selfish or as generous as he likes, with one proviso: if you refuse his offer, neither of you gets any money at all. What would it take for you to turn him down?

This is the scenario known to economists as the ultimatum game. Now the way we play it is generating remarkable insights into how the human brain drives financial decisionmaking, social interactions and even the supremely irrational behaviour of suicide bombers and gangland killers.

According to standard economic theory, you should cheerfully accept anything you are given. People are assumed to be motivated chiefly by rational self-interest, and refusing any offer, however low, is tantamount to cutting off your nose to spite your face.

Yet in practice derisory offers are declined all the time. Indeed, if the sum is less than £2.50, four out of five of us tell the selfish so-and-so to get lost. We get so angry at his deliberate unfairness that we are prepared to incur a cost to ourselves, purely to punish him.

Homo sapiens is clearly not Homo economicus, the ultra-rational being imagined by many professional economists.

An emerging fusion of economics, evolutionary psychology and neuroscience — neuro-economics in the jargon — is now starting to tell us why this is so.

Scientists yesterday published new evidence in the journal Science, showing not only how the brain makes difficult decisions but also that our choices can be changed when a critical part of the brain is switched off with magnets.

The researchers, Ernst Fehr and Daria Knoch, of the University of Zurich, used a technique called transcranial magnetic stimulation to tire out and thus temporarily suppress a part of the brain called the dorsolateral prefrontal cortex (DLPFC). Functional magnetic resonance imaging scans show that this is particularly active when people play the ultimatum game.

When the right DLPFC is shut down, the way they play starts to change. When given a low offer, they still feel it is deeply unfair. But, instead of rejecting it as they usually would, their selfish, ultra-rational side wins out over their emotional reaction against the other player’s meanness. They accept any amount of cash, however small.

The implication is not that the DLPFC is generating a sense of injustice — that was still there even when the region was knocked out. Rather, it seems to be more like an executive decision-maker, balancing the claims of emotion and reason.

“It is as if it is the referee that enforces fairness, and overrides narrow self-interest,” said David Laibson, Professor of Economics at Harvard University.

The results tend to support a very different theory of human behaviour from that favoured by classical economists. Our decisions seem not to be determined mainly by reason, but by a continuous battle between two sides of our psyches that are rooted in different mental circuits.

One of these is rational, controlled by the cortex — the cauliflower-like outer section of the brain where reasoning takes place, which is uniquely developed in humans. The other, however, is emotional, governed by the limbic system — the deeper-lying brain structures such as the amygdala that are much closer in character to the brains of other mammals.

George Loewenstein, Professor of Economics and Psychology at Carnegie Mellon University, in Pittsburgh, and one of the pioneers of neuro-economics, said: “The new science of neuro-economics is lending support to a very ancient view of human behaviour. That is the idea that there is a conflict and interaction between passion, and reason and self-interest.

“The now standard view of people as rational maximisers of self-interest is a very recent view. Neuroscience is telling us that that was a bit of a diversion. The rational side is a process that sometimes overrides the dominant interest on human behaviour, which is the passionate side.”

Interestingly, the DLPFC does not develop fully until early adulthood, offering a possible explanation for adolescent selfishness — the “Kevin the teenager” phenomenon.

Why might the brain want to overrule self-interest in the first place? Colin Camerer, Professor of Business Economics at the California Institute of Technology, says that it probably evolved that way.

If we always accepted low offers for the sake of tiny gains, we would rapidly get a reputation as a soft touch. Everybody else would try to bilk us at every turn. By acting apparently against our interests, we do better in the long run. Our ancestors were better at surviving if they were bloody-minded. Professor Camerer explained: “Emotion is nature’s way of letting people know that if you’re treated badly you’ll do something about it.”

Professor Laibson said: “One prospect is that, as we understand this brain research, we will be able to go beyond tweaking the classical model and develop a much richer understanding of how people make choices.”

What is starting to emerge is a more accurate — and recognisable — picture of human nature than classical economic theory provided. In many ways, it is a positive one, helping to explain the human capacity for kindness and co-operation, and the centrality of fairness to social norms. We are not acquisitive automatons conditioned always to follow narrow self-interest.

But it also has a dark side. The depth with which we feel injustice, and the way we respond to it emotionally, rather than rationally, may also underlie extreme reactions to perceived wrongs. The gang leader who has a rival murdered over a slight to his honour and the fundamentalist who takes out his grievance against the West by becoming a suicide bomber are both particularly high-stakes players of the ultimatum game.

Professor Loewenstein said: “In a sense, suicide bombers are playing a version of the ultimatum game. Their sense of injustice is such that they are willing to pay the highest possible cost. For models of behaviour which assume that self-interest is all important, it has always been a mystery why people go to war or sacrifice themselves for their nation, their religion, or even for abstract principles. To explain these types of behaviours, we need to take account of how human actions are governed by emotion.”

http://www.timesonline.co.uk/article/0,,2-2392997,00.html

[abdulhakeem]

Fairness switch in the brain

Friday, October 06, 2006

Civil society may hinge on a tiny piece of tissue at the front of the human brain, a new study suggests.

Experiments involving a "fairness" game show that the right side of this region - called the dorsolateral prefrontal cortex - helps people suppress selfish urges in obviously unjust situations, even at their own expense.

When researchers used a mild electric current to temporarily short-circuit this area, the law of the jungle quickly reasserted itself.

Fairness sense switched off

People with disabled right-side dorsolateral prefrontal cortexes grabbed whatever money they could from lopsided transactions - even when they knew the deal they were getting was grossly unfair.


"They understood the unfairness of it all, but they simply couldn't inhibit their need for getting the money," said Paul Sanberg, director of the Centre of Excellence for Ageing and Brain Repair at the University of South Florida College of Medicine in Tampa.

Sanberg was not involved in the study, which is published in the October 6 issue of Science.

The Swiss and American team behind this research noted that, despite a long history of crime, wars and rapaciousness, human beings are innately cooperative. In fact, Homo sapiens is the only species to exhibit "reciprocal fairness" - the punishment of others' unfair behaviours, even in situations where doing so hurts the punisher.

Tested with ultimatum game

This behaviour is demonstrated in an oft-used tool in behavioural science called the "Ultimatum Game."


In this game, one player is given a set amount of money. He is then instructed to hand over, at his own discretion, a share of the money to a second player.

Player 2 can either accept the amount offered or refuse the deal altogether, in which case both players receive no money.

When Player 1's offer is very low - for example, $2 out of a total of $20 - it would still behoove Player 2 to accept the offer, since $2 is better than nothing.

However, under normal circumstances, participants put in this position in the game overwhelmingly refuse such low offers, which they perceive as grossly unfair. Instead, they forfeit their own self-interest so they can "punish" Player 1.

Why unfairness is punished

Why might this be so? Humans are highly socially evolved, and punishing unfairness "helps sustain cooperation in groups," said study lead researcher Ernst Fehr, director of the Institute for Empirical Research in Economics at the University of Zurich.


Because more cohesive groups tend to have better survival prospects, humans who suppress their immediate urges end up on the "winning team," evolutionarily speaking.

How the study was conducted

Fehr's group sought to find the seat of this selfishness-override in the brain.


In prior brain-imaging studies, the dorsolateral prefrontal cortex (DLPFC) lit up during the game, so the researchers focused there.

In the study, they had participants play the game under two conditions. In the first condition, the researchers passed a mild electric current through the right or left hemispheres of Player 2's DLPFC, temporarily deactivating these brain regions. Other participants took on the Player 2 role under sham conditions where no real electric current was flowing.
"The big surprise," Fehr said, "is that a relatively minor inhibition of the right DLPFC removes or weakens the subject's ability to override their self-interest."

DLPFC tied to fairness

Players whose right-side DLPFC's were "switched off" accepted even very low amounts of cash nearly half (45 percent) of the time - even though they knew the offer was terribly unfair.


But under normal conditions, barely one in 10 players accepted such insulting low offers, the researchers found.

The experiment shows that this part of the cortex "is clearly very important for our social behaviour, our societal evolution," Sanberg said. The right side of the DLPFC helps people resist those strong urges for sex, money and general acquisitiveness that come from more primitive sites outside the cortex, he said.

"It provides modulation of those urges, so that you can have control over them," Sanberg added. "As we evolved, we somehow developed this control over our basic needs."

The same in everyone?

One intriguing line of research is whether the right-side DLPFC functions similarly in everyone - even hardened criminals or sociopaths.

"This is a very interesting question which we are just exploring now," Fehr said. "Preliminary results suggest that the right DLPFC has very different activation across individuals."

His team also noticed that the left side of the DLPFC also sprang to life during the game, although its role remains much more mysterious. "We are just in the process of studying this now," Fehr said.

http://www.health24.com/news/Mind_Psychology/1-930,37847.asp

[Al-Nasser]

subhan Allah
subhan Allah
subhan Allah

confirming another study.........and confirming a very beautiful verse in the Quran

Nay! if he desist not, We would certainly smite his forehead,A lying, sinful forehead.Then let him summon his council,
096.015-017

[Al-Nasser]

also i was talking to a brother and he reminded me of the du'a you should say in the wedding night......you place your hand on your wife's forehead (and she do the same to you) and you say after bismallah "O' Allah grant me the good in her nature, and protect me from the evil in her nature"

[Umar`]

subhanAllah

[abdulhakeem]

Study Finds Brain Injury Changes Moral Judgment

March 21, 2007
By BENEDICT CAREY (http://topics.nytimes.com/top/reference/timestopics/people/c/benedict_carey/index.html?inline=nyt-per)

Damage to an area of the brain behind the forehead, inches behind the eyes, transforms the way people make moral judgments in life-or-death situations, scientists are reporting today. In a new study, people with this rare injury expressed increased willingness to kill or harm another person if doing so would save others' lives.

The findings are the most direct evidence to date that humans’ native revulsion for hurting others relies on a part of neural anatomy, one that likely evolved before the brain regions responsible for analysis and planning.

The researchers emphasize that the study was small and that the moral decisions were hypothetical; the results cannot predict how people with or without brain injuries will act in real life-or-death situations. Yet the findings, published online by the journal Nature, confirm the central role of the damaged region — the ventromedial prefrontal cortex, which is thought to generate social emotions, like compassion.

Previous studies showed that this region was active during moral decision-making, and that damage to it and neighboring areas from severe dementia affected moral judgments. The new study seals the case by demonstrating that a very specific kind of emotion-based judgment is altered when the region is offline. In extreme circumstances, people with the injury will even endorse suffocating an infant if that would save more lives.

“I think it’s very convincing now that there are at least two systems working when we make moral judgments,” said Joshua Greene, a psychologist at Harvard who was not involved in the study. “There’s an emotional system that depends on this specific part of the brain, and another system that performs more utilitarian cost-benefit analyses which in these people is clearly intact.”

The finding could have implications for legal cases. Jurors have reduced sentences based on brain-imaging results, and experts say that any evidence of damage to this ventromedial area could sway judgments of moral competency in some cases.

The new study focused on six patients who had suffered very specific damage to the ventromedial area from an aneurysm or a tumor (http://topics.nytimes.com/top/news/health/diseasesconditionsandhealthtopics/tumors/index.html?inline=nyt-classifier). The cortex is the thick outer wrapping of the brain, where the distinctly human, mostly conscious functions of thinking and language reside. The term ventral means underneath, and medial means near the middle. The area in adults is about the size of a child’s fist.

People with this injury can be lucid, easygoing, talkative and intelligent, but blind to subtle social cues, making them socially awkward. They also have some of the same moral instincts that others do.

The researchers, from the University of Iowa (http://topics.nytimes.com/top/reference/timestopics/organizations/u/university_of_iowa/index.html?inline=nyt-org) and other institutions, had them respond to several moral challenges. In one, they had to decide whether to divert a runaway boxcar that was about to kill a group of five workmen. To save they workers they would have to flip a switch, sending the car hurtling into another man, who would be killed.

They strongly favored flipping the switch, just as group of people without injuries did. A third group, with brain damage that did not affect the ventromedial cortex, made the same decision.

All three groups also strongly rejected doing harm to others in situations that were not a matter of trading one certain death for another. They would not send a daughter to work in the pornography industry to fend off crushing poverty, or kill an infant they felt they could not care for.

But a large difference in the participants’ decisions emerged when there was no switch to flip — when they had to choose between taking direct action to kill or harm someone (pushing him in front of the runaway boxcar, for example) and serving a greater good.

Those with ventromedial injuries were about twice as likely as the other participants to say they would push someone in front of the train (if that was the only option), or to poison someone with AIDS (http://topics.nytimes.com/top/news/health/diseasesconditionsandhealthtopics/aids/index.html?inline=nyt-classifier) who was bent on infecting others, or suffocate a baby whose crying would reveal to enemy soldiers where the subject and family and friends were hiding.

“The difference was very clear, for all of the ventromedial patients,” said Dr. Michael Koenigs, a neuroscientist at the National Institutes of Health (http://topics.nytimes.com/top/reference/timestopics/organizations/n/national_institutes_of_health/index.html?inline=nyt-org) who led the study while at the University of Iowa. After repeatedly endorsing killing in these high-conflict situations, he added, one patient told him, “Jeez, I’ve turned into a killer.”

The other authors were Dr. Daniel Tranel of Iowa and neuroscientists from Harvard, the University of Southern California (http://topics.nytimes.com/top/reference/timestopics/organizations/u/university_of_southern_california/index.html?inline=nyt-org) and the California Institute of Technology (http://topics.nytimes.com/top/reference/timestopics/organizations/c/california_institute_of_technology/index.html?inline=nyt-org).

The ventromedial area is a primitive part of the cortex that appears to have evolved to help humans and other mammals navigate social interactions. The area has connections to deeper, unconscious regions like the brain stem, which transmit physical sensations of attraction or discomfort; and the amygdala, a gumdrop of neural tissue that registers threats, social and otherwise. The ventromedial area integrates these signals with others from the cortex, including emotional memories, to help generate familiar social reactions.

“This area when it’s working will give rise to social emotions that we can feel, like embarrassment, guilt, compassion that are critical to guiding our social behavior,” said Dr. Antonio Damasio, a co-author and a neuroscientist at the Brain and Creativity Institute at U.S.C. These sensations in effect put a finger on the brain’s conscious, cost-benefit scale weighing moral dilemmas, Dr. Damasio argues, creating a tension that even trained snipers can feel when having to pull the trigger on an enemy.

This tension between cost-benefit calculations and instinctive emotion in part reflects the brain’s continuing adjustment to the vast social changes that have occurred since the ventromedial area first took shape. The ventromedial area most likely adapted to assist the brain in making snap moral decisions in small kin groups— to spare a valuable group member’s life after a fight, for instance. As human communities became larger and increasingly complex, so did the cortical structures involved in parsing ethical dilemmas. But the more primitive ventromedial area continued to anchor it with emotional insistence an ancient principle: respect for the life of another human being.

“A nice way to think about it,” Dr. Damasio said, “is that we have this emotional system built in, and over the years culture has worked on it to make it even better.”

http://www.nytimes.com/2007/03/21/health/21cnd-brain.html (http://www.nytimes.com/2007/03/21/health/21cnd-brain.html?_r=5&partner=MYWAY&pagewanted=print&oref=slogin&oref=slogin&oref=slogin&oref&oref=login)