Increased brain activity in older adults exhibiting symptoms of Alzheimer’s disease helps them compensate for negative changes associated with the disease, reports a study published this week in Nature Neuroscience.
Alzheimer’s disease is associated with the accumulation of a protein known as beta amyloid (Aβ) in the brain, resulting in damage to brain cells.
William Jagust and colleagues used functional magnetic resonance imaging to track brain activity of healthy young adults and older adults, as well as older adults with documented brain Aβ deposits, as they tried to memorize pictures of scenes. Both groups of older people did equally well in this task. However, in young adults, and in older adults with Aβ accumulation, activity in the visual and memory areas of the brain correlated directly with an increase in memory of the details of the scene. In contrast, for older adults with no Aβ accumulation, lower activity in areas not generally associated with vision and memory, was a greater predictor of how well they remembered the details of the scenes.
These results suggest that greater activity in individuals with Aβ brain accumulation might be the result of the brain adapting to the damage caused by Aβ in an effort to maintain normal function.