Word: cortex
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...humans later) feels the stress, in this case an electric shock. The rat's senses immediately send a message to the central portion of its brain, where the stimulus activates two neural pathways. One of these pathways is a relatively long, circuitous route through the cortex, where the brain does its most elaborate and accurate processing of information. The other route is a kind of emergency shortcut that quickly reaches an almond-shaped cluster of cells called the amygdala...
...this point, the other half of the stress signal has reached the cortex, which confirms that there's a danger present and figures out that it's causing pain. Once the shock has warn off, a part of the brain called the prefrontal cortex sends out an all-clear message and lets the amygdala know that it's O.K. to stand down. At least it's supposed to. It seems that it's harder to turn off a stress response than to turn it on. This makes sense, in terms of survival. After all, it's better to panic unnecessarily...
...many ways, study after study has found, autistic people do not parse information as others do. University of Illinois psychologist John Sweeney, for example, has found that activity in the prefrontal and parietal cortex is far below normal in autistic adults asked to perform a simple task involving spatial memory. These areas of the brain, he notes, are essential to planning and problem solving, and among their jobs is keeping a dynamically changing spatial map in a cache of working memory. As Sweeney sees it, the poor performance of his autistic subjects of the task he set for them--keeping...
These are the neuron-packed gray matter of the cerebral cortex and white matter, which contains the fibrous connections projecting to and from the cerebral cortex and other areas of the brain, including the cerebellum. Perhaps, Courchesne speculates, it is the signal overload caused by this proliferation of connections that injures the Purkinje cells and ultimately kills them. "So now," says Courchesne, "a very interesting question is, What's driving this abnormal brain growth? If we could understand that, then we might be able to slow or stop...
...from the inside of her skull. A video camera, worn on a cap, transmits images in the form of radio signals to the stimulator, which converts these signals into electrical impulses and sends them along Marie's optic nerve. The optic nerve ferries the signals to Marie's visual cortex, where they are reassembled into an image: in this case, a collection of red, blue and yellow Lego bricks. "The device is an integral part of my body," Marie says. "I don't feel it. I completely ignore it." Marie is one of only about a dozen people...