Here is a chilling little item from Pieperhoff et al., who examined MRI images of the brains of 51 healthy male subjects from 18 to 51 years old. They found age-related volume declines in circumscribed brain regions: the sensorimotor system, encompassing the cerebellum, thalamus, somatosensory and motor cortices, and the prefrontal system, encompassing the anterior cingulate as well as the lateral and basomedial frontal cortices. Regions belonging to other functional systems, such as the auditory system or the visual system, did not show such age–volume relationships.
Horizontal sections of the reference brain with statistical maps, showing the t values of age-related volume decline and increase. t values were calculated by a two-sided t test for a linear regression in the voxels of the LVR maps, depending on age.