False recall and false recognition: An examination of the effects of selective and combined lesions to the medial temporal lobe diencephalon and frontal lobe structures

The present experiment examined the false recall and false recognition of nonstudied words that are preceded by a list of strong associates in patients with amnesia due to damage restricted to medial temporal lobe or diencephalic regions (MTL/D amnesics), in nonamnesic patients with damage restricted to the frontal lobes (FL nonamnesics), and in amnesic patients with damage to the frontal lobes in addition to medial temporal lobe damage (FL amnesics). We used the Deese/Roediger and McDermott paradigm (Deese, 1959; Roediger & McDermott, 1995) in which people frequently claim that nonstudied words appeared on a presented list. At immediate free recall, the results taken together showed that MTL/D amnesic patients and FL nonamnesic patients produced higher levels of false memory than did controls. At recognition both types of amnesic patients produced less false recognition than either frontal-lobe patients or controls. The results are consistent with the hypothesis that abnormally high levels of false memories are related to the following three conditions: (1) partial memory for the word lists, (2) the ability to extract the semantic gist of the list, and (3) a deficit in strategic monitoring processes.