title: False item recognition in patients with Alzheimer's disease.
abstract: Recent evidence suggests that patients with Alzheimer's disease (AD), as compared with normal individuals, exhibit increased false recognition by stimulus repetition in the Deese-Roediger-McDermott (DRM) task or associative recognition memory tasks, probably due to impaired recollection-based monitoring. However, because of possible alternative explanations for the findings of these previous studies, the evidence for impaired recollection-based monitoring in AD patients remains inconclusive. In this study, we employed stimulus repetition in old/new recognition judgments of single-item picture memory without a factor of association between the stimuli and examined whether AD patients showed increased false item recognition as compared with healthy controls. AD patients and healthy controls studied single-item pictures presented either once or three times. They were later asked to make an old/new recognition judgment in response to (a) Same pictures, pictures identical to those seen at encoding, (b) Similar lures, novel pictures similar to but not identical to those seen at encoding, and (c) Dissimilar lures, novel pictures not similar to those seen at encoding. For Same pictures, repeated presentation of stimuli increased the proportion of "old" responses in both groups. For Similar lures, repeated presentation of stimuli increased the rate of "old" responses in AD patients but not in control subjects. The results of the present study clearly demonstrated elevated false recognition by stimulus repetition in single-item recognition in AD patients. The present findings strongly support the view that AD patients are impaired in their ability to use item-specific recollection in order to avoid false recognition.
authors.affiliation: Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Abe
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Fujii
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Nishio
authors.forename: Osamu
authors.initials: O
authors.lastname: Iizuka
authors.forename: Shigenori
authors.initials: S
authors.lastname: Kanno
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kikuchi
authors.forename: Masahito
authors.initials: M
authors.lastname: Takagi
authors.forename: Kotaro
authors.initials: K
authors.lastname: Hiraoka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamasaki
authors.forename: Hyunjoo
authors.initials: H
authors.lastname: Choi
authors.forename: Kazumi
authors.initials: K
authors.lastname: Hirayama
authors.forename: Mayumi
authors.initials: M
authors.lastname: Shinohara
authors.forename: Etsuro
authors.initials: E
authors.lastname: Mori
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000523:psychology*; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology