New research results strongly suggest that cocaine bites the hand that feeds it, in essence, by harming or even killing the very brain cells that trigger the “high” that cocaine users feel. This most comprehensive description yet of cocaine-induced damage to key cells in the human brain’s dopamine “pleasure center” may help explain many aspects of cocaine addiction, and perhaps aid the development of anti-addiction drugs. It also could help scientists understand other disorders involving the same brain cells, including depression.
A new study by a University of Arkansas psychologist proposes that beliefs about the afterlife may amount to more than a cultural construct. They may in fact have a biological basis ? arising from the human brain’s unique ability to comprehend the mental states of other people. “The vast majority of cultures, if not all of them, have developed some theory about what happens to personal consciousness after death. Even in our own culture, 82 percent of Americans believe in some form of personal continuation after death,” said the study’s lead author. “There are superficial differences in religious beliefs between cultures, but those all arise out of the same question. Beliefs in an afterlife ? or at least thoughts about life after death ? are both universal and natural.”
When the human brain is presented with conflicting information about an object from different senses, it finds a remarkably efficient way to sort out the discrepancies, according to new research conducted at the University of California, Berkeley. The researchers found that when sensory cues from the hands and eyes differ from one another, the brain effectively splits the difference to produce a single mental image. The researchers describe the middle ground as a “weighted average” because in any given individual, one sense may have more influence than the other. When the discrepancy is too large, however, the brain reverts to information from a single cue – from the eyes, for instance – to make a judgment about what is true.
When you look at a picture, your brain has to put together lines, patterns and shapes to make a meaningful scene. New research by neuroscientists at the University of California, Davis and the University of Minnesota shows that higher regions of the brain can quickly recognize patterns and shapes and tell lower areas of the brain to stop processing the information. The finding confirms predictions from computer models and helps explain how the human brain makes sense of what the eyes see.