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How I See It
Jun. 5th, 2013 06:58 amThese paragraphs about how the brain supposedly works come from an article about infant fatalities in cars.
The human brain, he says, is a magnificent but jury-rigged device in which newer and more sophisticated structures sit atop a junk heap of prototype brains still used by lower species. At the top of the device are the smartest and most nimble parts: the prefrontal cortex, which thinks and analyzes, and the hippocampus, which makes and holds on to our immediate memories. At the bottom is the basal ganglia, nearly identical to the brains of lizards, controlling voluntary but barely conscious actions.
Diamond says that in situations involving familiar, routine motor skills, the human animal presses the basal ganglia into service as a sort of auxiliary autopilot. When our prefrontal cortex and hippocampus are planning our day on the way to work, the ignorant but efficient basal ganglia is operating the car; that's why you'll sometimes find yourself having driven from point A to point B without a clear recollection of the route you took, the turns you made or the scenery you saw.
Ordinarily, says Diamond, this delegation of duty "works beautifully, like a symphony. But sometimes, it turns into the '1812 Overture.' The cannons take over and overwhelm."
By experimentally exposing rats to the presence of cats, and then recording electrochemical changes in the rodents' brains, Diamond has found that stress -- either sudden or chronic -- can weaken the brain's higher-functioning centers, making them more susceptible to bullying from the basal ganglia. He's seen the same sort of thing play out in cases he's followed involving infant deaths in cars.
( Here's my interpretation regarding what I view are common misconceptions about the brain held by pretty much everyone, including most neuroscientists. )
The human brain, he says, is a magnificent but jury-rigged device in which newer and more sophisticated structures sit atop a junk heap of prototype brains still used by lower species. At the top of the device are the smartest and most nimble parts: the prefrontal cortex, which thinks and analyzes, and the hippocampus, which makes and holds on to our immediate memories. At the bottom is the basal ganglia, nearly identical to the brains of lizards, controlling voluntary but barely conscious actions.
Diamond says that in situations involving familiar, routine motor skills, the human animal presses the basal ganglia into service as a sort of auxiliary autopilot. When our prefrontal cortex and hippocampus are planning our day on the way to work, the ignorant but efficient basal ganglia is operating the car; that's why you'll sometimes find yourself having driven from point A to point B without a clear recollection of the route you took, the turns you made or the scenery you saw.
Ordinarily, says Diamond, this delegation of duty "works beautifully, like a symphony. But sometimes, it turns into the '1812 Overture.' The cannons take over and overwhelm."
By experimentally exposing rats to the presence of cats, and then recording electrochemical changes in the rodents' brains, Diamond has found that stress -- either sudden or chronic -- can weaken the brain's higher-functioning centers, making them more susceptible to bullying from the basal ganglia. He's seen the same sort of thing play out in cases he's followed involving infant deaths in cars.
( Here's my interpretation regarding what I view are common misconceptions about the brain held by pretty much everyone, including most neuroscientists. )
