Effect of dendrite structure cracked#

The brain, more than any other organ, is where experience becomes flesh. Ultimately, he hopes to find, for instance, that Anthony Mann’s plan to become a pilot and Brandon’s to study law will lead to brain differences that are detectable on future MRIs. By following twins, who start out with identical - or, in fraternal twins, similar - programming but then diverge as life takes them on different paths, he hopes to tease apart the influences of nature and nurture. Although most brain development seems to follow a set plan, with changes following cues that are preprogrammed into genes, other, subtler changes in gray matter reflect experience and environment. In recent years, Giedd has shifted his focus to twins, which is why the Manns are such exciting recruits. Increasingly, the wild conduct once blamed on “raging hormones” is being seen as the by-product of two factors: a surfeit of hormones, yes, but also a paucity of the cognitive controls needed for mature behavior. These diseases typically begin in adolescence and contribute to the high rate of teen suicide. Some experts believe the structural changes seen at adolescence may explain the timing of such major mental illnesses as schizophrenia and bipolar disorder.

Effect of dendrite structure cracked#

Now that MRI studies have cracked open a window on the developing brain, researchers are looking at how the newly detected physiological changes might account for the adolescent behaviors so familiar to parents: emotional outbursts, reckless risk taking and rule breaking, and the impassioned pursuit of sex, drugs and rock ‘n’ roll. If we had to pick a number now, we’d probably go to age 25.” “When we started,” says Giedd, “we thought we’d follow kids until about 18 or 20. Giedd’s scanning studies proved what every parent of a teenager knows: not only is the brain of the adolescent far from mature, but both gray and white matter undergo extensive structural changes well past puberty. Some theorists concluded from this that the idea of adolescence was an artificial construct, a phenomenon invented in the post-Industrial Revolution years. Not only is it full-grown in size, Giedd explains, but “in a lot of psychological literature, traced back to Piaget, the highest rung in the ladder of cognitive development was about age 12 - formal operations.” In the past, children entered initiation rites and started learning trades at about the onset of puberty. “And the adolescent studies have been the most surprising of all.”īefore the imaging studies by Giedd and his collaborators at UCLA, Harvard, the Montreal Neurological Institute and a dozen other institutions, most scientists believed the brain was largely a finished product by the time a child reached the age of 12. “It turned out that normal brains were so interesting in themselves,” he marvels. In a way, the vast project that has become his life’s work is nothing more than an attempt to establish a gigantic control group. Giedd started out investigating the developmental origins of attention-deficit/hyperactivity disorder (ADHD) and autism (“I was going alphabetically,” he jokes) but soon discovered that so little was known about how the brain is supposed to develop that it was impossible to figure out where things might be going wrong. For each volunteer, he creates a unique photo album, taking MRI snapshots every two years and building a record as the brain morphs and grows. Giedd, 43, has devoted the past 13 years to peering inside the heads of 1,800 kids and teenagers using high-powered magnetic resonance imaging (MRI). Jay Giedd (pronounced Geed), chief of brain imaging in the child psychiatry branch at the National Institute of Mental Health.