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.

Perceptually or conceptually driven recognition: On the specificities of the memory deficit in schizophrenia

“…The fact that the between-group difference was observed only in the inclusion situation appears a priori inconsistent with previous studies showing spared familiarity in schizophrenia (e.g., Huron and Danion, 2002;Weiss et al, 2002;Huron et al, 2003;Van Erp et al, 2008;Grillon et al, 2010). Previous PDP studies have shown an impairment of consciously controlled use of memory during list discrimination and stem completion tasks (Kazes et al, 1999;Linscott and Knight, 2001).…”

“…Many studies have shown that conscious recollection is consistently impaired in schizophrenia, while familiarity is generally spared (Brébion et al, 2002;Nieznanski, 2002;Achim and Lepage, 2003;Moritz et al, 2003;Bonner-Jackson et al, 2008;Tendolkar et al, 2002;Van Erp et al, 2008). Conscious recollection has been found to be consistently impaired for words (Huron et al, 1995;Huron and Danion, 2002;Van Erp et al, 2008;Grillon et al, 2010; see also Tendolkar et al (2002)), line drawings (Huron et al, 2003) and pictures of pairs of objects . While the Remember/Know procedure (Gardiner, 1988) has been the most used in this context, alternative methods such as the process-dissociation procedure (PDP), which contrasts situations of inclusion and exclusion (Jacoby, 1991) or receiver operating characteristics (ROCs: e.g., Yonelinas, 1994) based on confidence judgments have been also used.…”

Mismatched expressions decrease face recognition and corresponding ERP old/new effects in schizophrenia.

“…In line with our hypotheses, between-group ERP differences were observed when participants were required to treat both unchanged old faces (old condition) and old faces with a new expression (different condition) as old. This result suggests that patients with schizophrenia are more sensitive to the expression change and appears to be inconsistent with studies showing spared familiarity in schizophrenia (Huron et al, 1995;van Erp et al, 2008;Weiss, Goff, Duff, Roffman, & Schacter, 2008). However, assuming that false recognition arises from an illusory familiarity, the absence of a between-groups difference in the false-alarm rates (YES to new) shows that patients with schizophrenia exhibited a spared capacity to distinguish repeated faces from new ones.…”

A Meta-Analysis of Autobiographical Memory Studies in Schizophrenia Spectrum Disorder

“…78,86 This may reflect patients' difficulty with spontaneously linking and organizing the different aspects of the material to be remembered. 87 These relational memory impairments described in schizophrenia 88,89 point to defective functioning of the hippocampus. 90 However, while with episodic memory research the material to be encoded can be controlled, it is difficult to experimentally check the "defective strategic encoding" assumption of AM deficits in schizophrenia, since personal events generally happened several years before the AM test.…”