After tests, doctors decided to scan his brain and discovered he had a large tumour in the middle of his brain, he was then referred to the Children's Hospital.

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The limbic brain is in the middle of the reptilian and cortical brains (both in terms of evolution and physical location).

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It is currently possible to see brain activity patterns in middle-aged individuals indicative of Alzheimer's disease, but that information doesn't always predict Alzheimer's, he said.

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Meningiomas represent about one-third of all primary brain tumors and are most frequently found in middle-aged women, the American Brain Tumor Association's website states.

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And although imaging studies show that middle-aged people may use different brain regions to do the same old tasks, cognitive tests show that apart from brute speed, the brain's abilities are not diminished in middle age.

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On a recent visit, I stood in the middle of a giant human brain, constructed from 256 MRI images.

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The researchers compared the results of tests of brain function on 33 amateur football players with those from 27 middle-distance runners and swimmers.

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Gene Block, a professor of psychiatry and biobehavioral sciences at University of California, Los Angeles, and colleagues found that by middle age, the signal the master body clock in the brain sends out to other internal clocks to help resynchronize the different processes gets weaker.

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