New research has found that a drug used to treat severe forms of acne, Roaccutane (Accutane in the US), reduces the availability of the chemical serotonin, low levels of which have been linked to aggression and clinical depression.

The researchers had previously reported that the drug caused depressive behaviour in mice but, until now, the mechanism by which this might happen was unknown.

Using cells cultured in a laboratory, scientists from the University of Bath (UK) and University of Texas at Austin (USA) were able to monitor the effect of the drug on the chemistry of the cells that produce serotonin.

Some people just don't express emotions. It used to be considered strictly cultural, a society's image manifested in physical expectations, but now true inability to express emotions (alexithymia) is thought to be hereditary.

The largest study so far has provided new data in the current issue of Psychotherapy and Psychosomatics. The role of genetic and environmental factors for developing alexithymia is still unclear, and the aim of this study was to examine these factors in a large population-based sample of twins.

The Toronto Alexithymia Scale-20 (TAS-20) was included in a mail survey of 46,418 individuals born between 1931 and 1982 and registered with the Danish Twin Registry. The response rate was 75.3%.

A diet low in carbohydrates may help stunt the growth of prostate tumors, according to a new study led by Duke Prostate Center researchers. The study, in mice, suggests that a reduction in insulin production possibly caused by fewer carbohydrates may stall tumor growth.

“This study showed that cutting carbohydrates may slow tumor growth, at least in mice,” said Stephen Freedland, M.D., a urologist at Duke University Medical Center and lead researcher on the study.

Several studies demonstrated that alcohol-dependent patients show altered responses to alcohol-related cues. It is assumed that the regular association of these cues with the ingestion of alcohol leads to conditioned reactions, motivating reward or relief craving and instigating drug intake.

A group of German investigators has reported on this phenomenon in the current issue of Psychotherapy and Psychosomatics. They used an innovative method for studying this issue: the measurement of startle reflex, which is the eyeblink response to a sudden loud noise, that is normally inhibited by a pleasant foreground and potentiated when unpleasant stimuli are presented.

In youth with attention deficit hyperactivity disorder (ADHD), the brain matures in a normal pattern but is delayed three years in some regions, on average, compared to youth without the disorder, an imaging study by researchers at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) has revealed.

The delay in ADHD was most prominent in regions at the front of the brain’s outer mantle (cortex), important for the ability to control thinking, attention and planning. Otherwise, both groups showed a similar back-to-front wave of brain maturation with different areas peaking in thickness at different times.

Chimpanzees crave roots and tubers even when food is plentiful above ground, according to a new study that raises questions about the relative importance of meat for brain evolution. The study documents a novel use of tools by chimps to dig for tubers and roots in the savanna woodlands of western Tanzania.

The chimps’ eagerness for buried treats offers new insights in an ongoing debate about the role of meat versus potato-like foods in the diet of our hominid ancestors, said first author Adriana Hernandez-Aguilar, who collected the field data for her doctoral research at the University of Southern California.

The debate centers on the diet followed by early hominids as their brain and body size slowly increased towards a human level.

A diet rich in fish, omega-3 oils, fruits and vegetables may lower your risk of dementia and Alzheimer’s disease, whereas consuming omega-6 rich oils could increase chances of developing memory problems, according to a study published in the November 13, 2007, issue of Neurology®. The study did not find any association between consuming corn oil, peanut oil, lard, meat or wine and lowering risk of dementia.

For the study, researchers examined the diets of 8,085 men and women over the age of 65 who did not have dementia at the beginning of the study. Over four years of follow-up, 183 of the participants developed Alzheimer’s disease and 98 developed another type of dementia.

Scientists at John Carroll University, working in its Lighting Innovations Institute, have developed an affordable accessory that appears to reduce the symptoms of ADHD. Their discovery also has also been shown to improve sleep patterns among people who have difficulty falling asleep.

The John Carroll researchers have created glasses designed to block blue light, therefore altering a person’s circadian rhythm, which leads to improvement in ADHD symptoms and sleep disorders.

The individual puts on the glasses a couple of hours ahead of bedtime, advancing the circadian rhythm. The special glasses block the blue rays that cause a delay in the start of the flow of melatonin, the sleep hormone. Normally, melatonin flow doesn’t begin until after the individual goes into darkness.

One of the foundations of Einstein's Special Relativity is that no particular frame of reference is better than any other - whether you're sitting on the couch or barreling through space on a rocket, physics doesn't change. On the other hand, as many physics undergrads learn, choosing the right reference frame can simplify your homework problems a lot.

Thanks to Einstein, physicists know that the world looks different depending on how fast you're moving.