SUSCEPTIBILITY TO MEMORY INTERFERENCE EFFECTS FOLLOWING FRONTAL-LOBE DAMAGE - FINDINGS FROM TESTS OF PAIRED-ASSOCIATE LEARNING

Patients with frontal lobe lesions were administered tests of paired-a ssociate learning in which cue and response words are manipulated to i ncrease interference across two study lists. In one test of paired-ass ociate learning (AB-AC test), cue words used in one list are repeated in a second list but are associated with different response words (e.g ., LION-HUNTER, LION-CIRCUS). In another test (AB-ABr test), words use d in one list are repeated in a second list but are rearranged to form new pairs. Compared to control subjects, patients with frontal lobe l esions exhibited disproportionate impairment of second-list learning a s a result of interference effects. In particular, patients exhibited the poorest performance during the initial trial of the second list, a trial in which interference effects from the first list would be most apparent. These findings suggest that the on-line control of irreleva nt or competing memory associations is disrupted following frontal lob e lesions. This disruption may be indicative of an impaired gating or filtering mechanism that affects not only memory function but other co gnitive function as well.