Word: braines
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
Evolution seems to have programmed this discomfort via a brain structure called the amygdalae, a pair of almond-shaped brain regions deep within each temporal lobe that control fear and the processing of emotion. It's your amygdalae that keep you from getting so close to another person that he could easily reach out, gouge an eye, and then drag your woman off by her hair. (See the top 10 scientific discoveries...
...results challenge the accepted notion that teens make dumb decisions because their brains are immature. Although previous research has shown that most teens' gray-matter structures - including those involved in decision-making - are less advanced than those of adults, as you would expect, until now no one had studied teens' white matter, which works along with gray matter to produce decisions. The key part of white matter is called myelin, a fatty substance that coats the individual neural strands, or axons, that make up white matter. Myelination of axons begins during childhood and is completed at the end of adolescence...
Berns and his colleagues recruited 91 kids ages 12 to 18 and asked them to fill out a questionnaire about their tendency to engage in behaviors such as driving without a license, having unprotected sex and using drugs. Then they had the kids undergo a relatively new kind of brain scan called diffusion tensor imaging, a type of magnetic resonance imaging that is used to look at dense tissues like white matter. After analyzing the scans, the authors found a strong correlation between how risky the students described their behavior to be and how sophisticated their white matter...
Another possible explanation is that some teenagers whose brains develop more quickly than others become uncomfortable with the gap between their biological capabilities and the social rules they must follow as kids. "Precocious development of these [white-matter] tracts may predispose some adolescents to engage in behaviors that society considers too adult in nature for their chronological age," the authors write. In other words, having a more mature brain may actually spur some kids to seek out new and potentially harmful experiences...
...risky behavior? Berns' team addressed this question by drug-testing the 91 research subjects. Only nine had actually done drugs - in each case, marijuana - but eight of those nine admitted their drug use in the survey. No students who tested negative falsely claimed to have tried drugs. The teen brain, it appears, can be often an honest thing - even if it's not always a wise...