A French study involving 36 healthy older adults (60-80), prescreened for amyloid deposits in the brain to exclude people who might have preclinical Alzheimer’s disease, has found a linear increase in gray matter volume in proportion to the number of years of education (7-20 years). Specifically, increases were seen in the right superior temporal gyrus, anterior cingulate gyrus, and left insular cortex, and metabolism also increased proportionately with years of education in the anterior cingulate gyrus, as did functional connectivity between anterior cingulate gyrus and the right hippocampus, left angular gyrus, right posterior cingulate, and left inferior frontal gyrus. This increased connectivity was associated with improved cognitive performance.
The conclusion is that both the structure of the brain and its function in old age are increased in proportion to the number of years of education.
 . Relationships between years of education and gray matter volume, metabolism and functional connectivity in healthy elders. NeuroImage [Internet]. 2013 ;83:450 - 457. Available from: http://www.sciencedirect.com/science/article/pii/S1053811913006903