Earlier this month, Seau was determined to have chronic traumatic encephalopathy, a neurodegenerative brain disease that can follow multiple hits to the head, the National Institutes of Health said.

CNN: January 23, 2013 -- Updated 2220 GMT (0620 HKT)

In a very small number of cases, inflammation of the brain (encephalitis) may follow.

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"You basically follow a dot with the mouse, your brain does a lot of work, and you get a final score, " said Jim Miller, USA Cycling's vice president of athletics.

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Also known as duloxetine, the new medicine is a follow-up to Prozac that works by keeping the brain from reabsorbing serotonin, as most antidepressants do, but also by targeting the reuptake of norepinephrine, which drugs like Prozac ignore.

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In a follow up study, the researchers showed that in older rats glucose levels in the active brain areas dropped by 48% during the maze task.

BBC: Thinking 'drains the brain'

Whether he follow this model remains hard to predict, particularly because temptations will increase to turn to brawn over brain as he confronts economic and national security crises and becomes familiar with the tools that Bush left behind.

CNN: Commentary: Obama can learn from Bush's failures