Memory and metamemory: Comparisons between patients with frontal lobe lesions and amnesic patients

Abstract

Metamemory refers to knowledge about one’s own memory capabilities. The accuracy of metamemory judgments (i.e., feeling of knowing) was tested in patients with frontal lobe lesions and control subjects. Their performance was compared to other findings for 6 patients with Korsakoff s syndrome and 5 other patients with amnesia. In Experiment 1, subjects were presented sentences and then asked to recall key words from each sentence. They then judged their feeling of knowing for nonrecalled items in terms of how likely they thought they would be to recognize the key words on a subsequent recognition test. Patients with frontal lobe lesions exhibited impaired feeling of knowing when memory was weakened by imposing a 1–3-day delay between sentence presentation and recall. Experiment 2 tested feeling-of-knowing accuracy for nonrecalled general-information questions. On this test, patients with frontal lobe lesions performed normally. The metamemory deficit observed in Experiment 1 suggests that the frontal lobes contribute, at least in part, to metamemory judgments. The 5 (non-Korsakoff) amnesic patients had intact metamemory functions, but patients with Korsakoff’s syndrome did not. These findings suggest that the metamemory impairment in patients with Korsakoff’s syndrome is due, in part, to frontal lobe pathology.