title: Remember and know judgments during recognition in chronic schizophrenia.
abstract: Deficits in learning and memory are among the most robust correlates of schizophrenia. It has been hypothesized that these deficits are in part due to reduced conscious recollection and increased reliance on familiarity assessment as a basis for retrieval. The Remember-Know (R-K) paradigm was administered to 35 patients with chronic schizophrenia and 35 healthy controls. In addition to making "remember" and "know" judgments, the participants were asked to make forced-choice recognition judgments with regard to details about the learning episode. Analyses comparing response types showed a significant reduction in "remember" responses and a significant increase in "know" responses in schizophrenia patients relative to controls. Both patients and controls recalled more details of the learning episode for "remember" compared to "know" responses, although, in particular for "remember" responses, patients recalled fewer details compared with controls. Notably, patients recognized fewer inter-item but not intra-item stimulus features compared with controls. These findings suggest deficits in organizing and integrating relational information during the learning episode and/or using relational information for retrieval. A Dual-Process Signal Detection interpretation of these findings suggests that recollection in chronic schizophrenia is significantly reduced, while familiarity is not. Additionally, a unidimensional Signal Detection Theory interpretation suggests that chronic schizophrenia patients show a reduction in memory strength, and an altered criterion on the memory strength distribution for detecting new compared with old stimuli but not for detecting stimuli that are remembered versus familiar. Taken together, these findings are consistent with a deficit in recollection and increased reliance on familiarity in making recognition memory judgments in chronic schizophrenia.
authors.affiliation: Department of Psychology, UCLA, Los Angeles, CA 90095, USA. vanerp@psych.ucla.edu
authors.forename: Theo G M
authors.initials: TG
authors.lastname: van Erp
authors.forename: Tyler A
authors.initials: TA
authors.lastname: Lesh
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Knowlton
authors.forename: Carrie E
authors.initials: CE
authors.lastname: Bearden
authors.forename: Molly
authors.initials: M
authors.lastname: Hardt
authors.forename: Katherine H
authors.initials: KH
authors.lastname: Karlsgodt
authors.forename: David
authors.initials: D
authors.lastname: Shirinyan
authors.forename: Vikas
authors.initials: V
authors.lastname: Rao
authors.forename: Michael F
authors.initials: MF
authors.lastname: Green
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Subotnik
authors.forename: Keith
authors.initials: K
authors.lastname: Nuechterlein
authors.forename: Tyrone D
authors.initials: TD
authors.lastname: Cannon
mesh_terms: D000328:Adult; D001245:Association Learning; D002908:Chronic Disease; D003072:Cognition Disorders / Q000175:diagnosis / Q000523:psychology; D035061:Control Groups; D005260:Female; D005556:Form Perception; D006801:Humans; D007600:Judgment; D016018:Least-Squares Analysis; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis* / Q000523:psychology; D011939:Mental Recall; D008960:Models, Psychological; D010775:Photic Stimulation; D021641:Recognition, Psychology; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D017603:Signal Detection, Psychological; D013647:Task Performance and Analysis; D014706:Verbal Learning