COMPARISON OF OLDER-PEOPLE AND PATIENTS WITH FRONTAL LESIONS - EVIDENCE FROM WORD LIST LEARNING

We examined the hypothesis that changes in memory performance of older normal participants are due to frontal lobe dysfunction by comparing three groups of normal individuals (young, middle-aged, and older) wit h three groups of patients who had documented lesions in specific fron tal regions: unilateral right, unilateral left, and bilateral. All par ticipants were given 4 successive learning trials on each of 3 lists o f words: unrelated, related but presented in a pseudo-random order, an d related and presented in a blocked format. We found significant corr espondences in performance between the older normal participants and t he(younger) frontal damaged groups. The qualitative nature of recall p erformance, particularly as measured by indices of organizational cont rol processes, was similar between older normals and patients with fro ntal damage, particularly those with right frontal damage, but differe nt from that normally exhibited by patients with focal limbic/memory d ysfunction. These results add to the evidence that at least some of th e decline in older people in tasks which measure executive or supervis ory abilities is due to frontal system dysfunction.