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Department of Psychology, UCLA, Los Angeles, CA 90095, USA.
Schizophrenia Research (Impact Factor: 3.92). 04/2008; 100(1-3):181-90. DOI: 10.1016/j.schres.2007.09.021
Source: PubMed


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.

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Available from: Katherine H Karlsgodt, Oct 04, 2015
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    • "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 (Danion et al., 1999). 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. "
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    ABSTRACT: This study explored the effects of exemplar changes on visual object recognition in patients with schizophrenia and paired control subjects. The experimental design was derived from the process-dissociation procedure (PDP: Jacoby, 1991). The objects presented at test could be the same exemplar as at study (physically identical picture), a different exemplar of the same object category, or a new, non-studied object. In the inclusion task, participants had to generalize their recognition to the conceptual level by accepting both different and identical exemplars as old. In the exclusion task, on the other hand, they had to accept only the same exemplars of the studied objects as old. Overall, performance was better on the inclusion task than on the exclusion task; schizophrenia patients performed worse than controls on the inclusion task but not the exclusion task, misrecognizing different exemplars more often than healthy controls. The present findings reveal that both recollection and familiarity are impaired in patients with schizophrenia, who present a relational, conceptually driven memory deficit. This deficit does not allow them to recognize an object as a member of a specific category independently of perceptual variations. This retrieval mode influences their subjective awareness of items׳ familiarity, and should be considered as a target for remediation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
    Psychiatry Research 12/2014; 225(3). DOI:10.1016/j.psychres.2014.11.060 · 2.47 Impact Factor
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    • "In schizophrenia, the literature has shown impairments in both recollection (Danion et al., 1999; Tendolkar et al., 2002; Lepage et al., 2006; van Erp et al., 2008) and familiarity (Martin et al., 2004; Guillaume et al., 2007; Weiss et al., 2008). While both of these processes can be impaired (for meta-analyses, see Achim and Lepage (2003), Pelletier et al.( 2005)), deficits in familiarity are less consistently observed, suggesting that familiarity can potentially be used as a compensatory mechanism in schizophrenia patients (for a review see Libby et al. (2013)). "
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    ABSTRACT: Schizophrenia is associated with severe episodic retrieval impairment. The aim of this study was to investigate the possibility that schizophrenia patients could improve their familiarity and/or recollection processes by manipulating the semantic coherence of to-be-learned stimuli and using deep encoding. Twelve schizophrenia patients and 12 healthy controls of comparable age, gender, and educational level undertook an associative recognition memory task. The stimuli consisted of pairs of words that were either related or unrelated to a given semantic category. The process dissociation procedure was used to calculate the estimates of familiarity and recollection processes. Both groups showed enhanced memory performances for semantically related words. However, in healthy controls, semantic relatedness led to enhanced recollection, while in schizophrenia patients, it induced enhanced familiarity. The familiarity estimates for related words were comparable in both groups, indicating that familiarity could be used as a compensatory mechanism in schizophrenia patients.
    Psychiatry Research 08/2014; 220(3). DOI:10.1016/j.psychres.2014.08.034 · 2.47 Impact Factor
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    • "Both parahippocampal regions, the entorhinal cortex and subiculum, as well as the medial prefrontal cortex could be part of a distributed system consisting of brain regions that are part of a system involved in stimulus recognition memory which interacts with another system involved in assigning an aversive valence to the stimulus. It is important to note here that a defect of recognition memory with recollection has been reported in patients with schizophrenia (Danion et al., 1999; Huron and Danion, 2002; Pelletier et al., 2005; Drakeford et al., 2006; Danion et al., 2007; van Erp et al., 2008; Libby et al., 2013). It is tempting to propose that neurodevelopmental defects of the same structures (temporal and prefrontal) result in a disruption of mnemonic processing capabilities and loss of LI expression in schizophrenia patients. "
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    ABSTRACT: The psychic disintegration characteristic of schizophrenia is thought to result from a defective connectivity, of neurodevelopmental origin, between several integrative brain regions. The parahippocampal region and the prefrontal cortex are described as the main regions affected in schizophrenia. Interestingly, latent inhibition (LI) has been found to be reduced in patients with schizophrenia, and the existence of a dopaminergic dysfunction is also generally well accepted in this disorder. In the present review, we have integrated behavioral and neurochemical data obtained in a LI protocol involving adult rats subjected to neonatal functional inactivation of the entorhinal cortex, the ventral subiculum or the prefrontal cortex. The data discussed suggest a subtle and transient functional blockade during early development of the aforementioned brain regions is sufficient to induce schizophrenia-related behavioral and dopaminergic abnormalities in adulthood. In summary, these results support the view that our conceptual and methodological approach, based on functional disconnections, is valid for modeling some aspects of the pathophysiology of schizophrenia from a neurodevelopmental perspective.
    Frontiers in Behavioral Neuroscience 04/2014; 7:118. DOI:10.3389/fnbeh.2013.00118 · 3.27 Impact Factor
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