Sunday, February 03, 2008
An Adjunct To My Last
Just within the past few months, several groups of researchers have added support for the growing consensus that plenty can be done to slow the age-related declines in memory, mental speed, and decision making that affect most people. In November, a team from the Mayo Clinic and the University of Southern California announced that one computer-based mental training program appeared to improve older people's cognitive performance by as much as 10 years.Even in early adulthood the normal brain begins losing processing capacity in the form of brain tissue. In the past, the theory was that this loss was absolute, but now we know differently:
Then, in the 1970s, researchers showed that new brain cells and neural pathways form through the end of life. "This was the beginning of the brain plasticity movement," says Cohen, "the understanding that when we challenge our brains, the brain cells sprout new dendrites, which results in increased synapses, or contact points."That's really an amazing result with a very long endurance of benefit. If, instead of looking at people who have been diagnosed with PVS as liabilities to be killed off, we tried harder to help them, there is a least a possibility that we would learn enough about what produces results to maintain independent living for millions upon millions of elderly people. There are relatively few younger people in PVS, because if not killed off the condition tends to go one way or another - gradual improvement in function and emergence into a more obviously conscious state, or death. However there is a huge group of older people in most western societies, and maintaining good mental function for those people would effect a huge reduction in costs for that population.
In 2006, for example, a controlled clinical study of more than 2,000 older people by researchers at Pennsylvania State University, Indiana University, Johns Hopkins University, and elsewhere found that those who received 10 60-to-75-minute training sessions in reasoning—specifically, in recognizing word, number, and letter patterns and filling in the next item in a series—reported less difficulty with such activities of daily living as understanding instructions on a medication label. The effects still were apparent five years later.
And, of course, there is application to younger people who just want to stretch their capabilities, or to stroke victims, etc.
It should not have taken medicine as long as it has to figure out that brains are truly plastic, because almost as soon as we developed imaging techniques for the brain doctors realized that there were some people walking around with very normal mental function who had gross abnormalities of the brain. See Lorber's work. There appear to be documented cases of people with well above average IQs who have total brain tissue of less than 1/3rd normal. Lorber's most extreme case was truly bizarre:
Although the boy had an IQ of 126 and had a first class honours degree in mathematics, he had "virtually no brain". A noninvasive measurement of radio density known as CAT scan showed the boy's skull was lined with a thin layer of brain cells to a millimeter in thickness. The rest of his skull was filled with cerebrospinal fluid.If you are interested in the topic of how the brain really works, Indiana University's Shufflebrain page has a huge range of links. What interests me about Lorber's work is that in the worst category, there was a sharp divergence between good function and profound retardation.