Frontal-striatal circuits in cognitive aging: Evidence for caudate involvement

Changes in cognition with aging have been claimed to be due in large part t o a decline in frontal lobe function. However, at our present state of know ledge, the emphasis on the frontal lobes to the exclusion of the rest of th e frontal-striatal circuits of which they are a part is unwarranted. To arg ue this point, I consider another anatomical candidate within these circuit s, the caudate. Evidence is presented that the caudate decreases in size wi th age as much as the frontal lobes and that damage to either the frontal l obes or the caudate is accompanied by declines in inhibitory processes, exe cutive control, and cognitive speed similar to those seen in normal aging. Separating the unique contributions of the frontal lobes and the caudate to these circuits is difficult but should be the focus of future studies of t he biological basis of cognitive aging.