This is done by examining the combined concentration of gray and white matter, or nerve cells and fiber tracts, in parts of the brain not normally used for verbal processing the hippocampus and cerebellum, normally associated with memory and motor learning.

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Scanning their brains using functional magnetic resonance imaging, the scientists found that a region involved in language processing - the temporal lobe, part of the prefrontal cortex - was activated during verbal learning in rested patients.

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