The relationship between fact and source memory: Findings from amnesic patients and normal subjects

Abstract

Amnesic patients and normal subjects were presented 20 obscure facts to learn, and, after a 2-h delay, were given tests of fact recall, fact recognition, and source recall. The subjects were also given a recognition memory test in which they were asked about the learning session itself (event memory test). The amnesic patients exhibited marked impairment on all tests. Impaired source recall (i.e., source amnesia) appeared to be unrelated to impaired fact or event memory. That is, patients who made source errors remembered the facts and the learning session as well as did patients who did not make source errors. In a second experiment, normal subjects were tested 1, 3, 6, and 8 weeks after learning. Source recall dropped sharply after a 6- or 8-week retention interval, demonstrating that source amnesia can occur in normal subjects when they are tested long after learning. For the normal subjects, fact and source memory were correlated. Thus, in normal subjects, source amnesia can reflect the loss of fact memory, event memory, and associations between them. However, in amnesic patients, source memory impairment was unrelated to the severity of impaired fact or event memory. Source memory impairment may reflect a specific deficit in the association of facts with their contexts.