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THURSDAY, Oct. 5 (HealthDay News) -- 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.

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 Center of Excellence for Aging 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 Oct. 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 behaviors, even in situations where doing so hurts the punisher.

This behavior is demonstrated in an oft-used tool in behavioral 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 overwhelming refuse such low offers, which they perceive as grossly unfair. Instead, they forfeit their own self-interest so they can "punish" Player 1.

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.

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."

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 behavior, 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."

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.

More information

There's more on the brain and brain imaging at the U.S. National Institutes of Health.

SATURDAY, Oct. 7 (HealthDay News) -- High blood pressure is associated with sleep breathing problems in children, say U.S. researchers.

Their study of 20 children, aged 4 to 18, found that 60 percent of them had sleep-disordered breathing (SDB), which includes obstructive sleep apnea and obstructive hypoventilation -- a condition where breathing isn't adequate to meet the body's needs.

The findings were expected to be presented Oct. 7 at an American Heart Association meeting in San Antonio.

"SDB is important because it can result in daytime sleepiness, limited attention span, poor school performance, hyperactivity, poor growth and increased blood pressure in the lungs," study author Dr. Alisa A. Acosta, a fellow in pediatric kidney disease and hypertension at the University of Texas Medical School at Houston, said in a prepared statement.

"We know there's a link in adults between obstructive sleep apnea -- the most common of the SDBs -- and high blood pressure, so we were curious to see if the same link exists in our pediatric population," Acosta said.

Known risk factors for SDB in children are obesity and enlarged tonsils. The study suggested that high blood pressure is also a risk factor. Symptoms of SDB in children include snoring, restless sleep, morning headaches and excessive daytime sleepiness.

More information

The Nemours Foundation has more about children and high blood pressure  .

FRIDAY, Oct. 6 (HealthDay News) -- Newer, "second-generation" antipsychotic drugs don't appear to be significantly better than older drugs for schizophrenia patients who require a change in medication, British researchers report.

The results contradict the widely held belief that second-generation antipsychotic drugs are safer and more effective in treating schizophrenia than less-costly first-generation antipsychotic medicines, said researchers from the University of Cambridge.

In this study, 118 patients took first-generation drugs and 109 patients took second-generation drugs. After 12 weeks of treatment, quality-of-life scores for those taking the first-generation drugs averaged 49.2, compared with 46.6 for those taking the second-generation drugs.

After 26 weeks, the scores were 49.2 for first-generation and 50.4 for second-generation. After one year, the scores were 53.2 for first-generation and 51.3 for second-generation.

"Participants reported no clear preference for either drug group; costs were similar," wrote the study authors, who also noted their findings match some recent U.S. studies.

"All the data suggest that careful prescribing of first-generation antipsychotics, at least in the context of a trial, is not associated with poorer efficacy or a greater adverse effect burden, both of which would translate into lower quality of life in the medium term," the authors noted.

The study was published in the October issue of the Archives of General Psychiatry.

More information

The National Mental Health Association has more about schizophrenia  .

TUESDAY, Oct. 3 (HealthDay News) -- New insights into how genes affect an individual's response to particular drugs could someday speed the effective treatment of depression, researchers say.

Reporting in the Oct. 4 issue of the Journal of the American Medical Association, scientists say variations in a serotonin transport gene accurately predicted which patients would respond to selective serotonin reuptake inhibitor (SSRI) drugs such as Prozac.

They also identified key variations in the norepinephrine transporter (NET) gene. Those variants predicted response to nortriptyline, an antidepressant in a class of drugs called norepinephrine reuptake inhibitors (NRIs).

"I don't think this is going to change the way we treat depression, but it's another piece of the puzzle that will help us individualize treatment," said Dr. Julio Licinio, chairman of psychiatry at the University of Miami Miller School of Medicine. He was not involved in the research.

The study, conducted by researchers in the United States and Korea, shows "that it's important to look at gene variants in terms of treatment response," Licinio said.

Some 30 percent to 40 percent of patients fail their first drug treatment for major depression. Experts say that, right now, it's not possible to predict with any degree of accuracy which drug will work best for each patient.

Clinicians are pinning future hopes on "pharmacogenetics," or genetic factors that influence an individual's response to drugs.

There's reason for some optimism. Previous studies have shown that polymorphisms (individual differences in the DNA sequence) in the serotonin transporter gene might predict response to SSRIs, which include drugs such as Celexa, Paxil, Prozac and Zoloft.

Ethnic variations may also play a role. Prior studies have shown that gene variants linked to poor response to SSRIs among white patients were actually associated with a good response in Japanese and Korean patients.

"This raises some basic genetic questions about what exactly is the signal coming from the polymorphisms as to function and as to interaction with the drugs," Bernard Carroll, co-author of the research and scientific director of the Pacific Behavioral Research Foundation in Carmel, Calif., said in a prepared statement. "And it serves as a caution that results found in one ethnic group can't necessarily be transposed straight across to another ethnic group."

The new research was conducted at Samsung Medical Center in Seoul and was supported by the South Korean Ministry of Health and Welfare.

The study authors tracked the outcomes of a group of 241 Koreans diagnosed with major depression that had begun, on average, in the individuals' early-to-mid 50s.

The researchers were interested in two different types of antidepressants and associated pathways in the body: SSRIs and the serotonin transporter gene, as well as NRIs and the associated norepinephrine transporter (NET) gene.

Participants were treated for six weeks with an SSRI (either Prozac or Zoloft) or the NRI nortriptyline (brand names Aventyl or Pamelor).

Individuals who carried the "GG" polymorphism of NET had a better rate of response to NRI treatment than to SSRI treatment (83.3 percent and 58.7 percent, respectively).

"That's a 25 percent difference in response rate, so that is going to have a major impact, we would predict, on clinical practice," Carroll said.

The research also confirmed that response to SSRIs was associated with a genetic variation in the serotonin transporter gene.

Although the findings are preliminary and need to be replicated, particularly in a white population, "we're certainly optimistic that it's going to stand up," Carroll said.

More than half (56 percent) of Koreans and about 45 percent of whites have the GG polymorphism, the researchers noted.

"This is likely to still be a major finding in [whites] if the replications studies hold up," Carroll said. "If our findings are confirmed and if this genotyping is taken up in clinical services, then the market for SSRI drugs as first-line treatment will fall by around 50 percent. Another implication is that new drug development will shift to dual-action agents."

"The word is now out that depression is a very serious disorder with major public health and economic consequences," he continued. "There is a great deal of motivation on the professional side to do a better job of treating depression and this genetic prediction is an obvious place to start."

More information

For more on depression, visit the U.S. National Institute of Mental Health.