Memory and metamemory: a study of the feeling-of-knowing phenomenon in amnesic patients.

Accuracy of the feeling of knowing was tested in patients with Korsakoff's syndrome, patients prescribed electroconvulsive therapy, four other cases of amnesia, and control subjects. In Experiment 1, we tested feeling-of-knowing accuracy for the answers to general information questions that could not be recalled. Subjects were asked to rank nonrecalled questions in terms of how likely they thought they would be able to recognize the answers and were then given a recognition test for these items. Only patients with Korsakoff's syndrome were impaired in making feeling-of-knowing predictions. The other amnesic patients were as accurate as control subjects in their feeling-of-knowing predictions. In Experiment 2, we replicated these findings in a sentence memory paradigm that tested newly learned information. The results showed that impaired metamemory is not an obligatory feature of amnesia, because amnesia can occur without detectable metamemory deficits. The impaired metamemory exhibited by patients with Korsakoff's syndrome reflects a cognitive impairment that is not typically observed in other forms of amnesia.