Spatial-memory deficit in schizophrenia spectrum disorders under viewpoint-independent demands in the virtual courtyard task

Abstract

This study builds upon our previous work indicating that impaired hippocampal-dependent forms of memory are core to schizophrenia. Using a virtual-reality courtyard task, we presented participants with schizophrenia spectrum disorders (SSD; n = 20) and a healthy community comparison group (n = 20) with objects to remember within a town square, followed by a recognition test of the location of objects from either the same viewpoint or a shifted viewpoint relative to initial presentation. The SSD group demonstrated a relative deficit under shifted- compared to same-view conditions. These findings provide further support for deficient hippocampal-dependent cognition in SSD.

Selective deficit in spatial memory strategies contrast to intact response strategies in patients with schizophrenia spectrum disorders tested in a virtual navigation task

“…Moreover, despite correlations with a subset of participant characteristics, the differential impairment of the SDD‐Spatial group remained robust to covariate analyses and further follow‐up analyses assessing the influence of demographic, cognitive, and clinical variables. Overall, these behavioral findings support hypotheses of a selective hippocampal‐dependent memory dysfunction in SCZ with relatively intact functioning of response‐based systems (Keri et al, ; Hanlon et al, ; Weniger and Irle, ; Girard et al, ; Wilkins et al, ). This conclusion is in line with evidence that use of a spatial strategy depends on the integrity and recruitment of the hippocampi (O'Keefe, ; Smith and Milner, ), whereas response strategies are associated with the caudate nucleus in humans (Hartley et al, ; Iaria et al, ; Bohbot et al, ) and striatum (which includes the caudate nucleus) in rats (Packard et al, ; McDonald and White, ).…”

“…The overall pattern of memory impairment in some SCZ samples appears comparable to that of individuals with medial‐temporal lobe (MTL) lesions (Ornstein et al, ; Bartholomeusz et al, ). This study builds upon this literature and our findings of episodic and allocentric spatial memory deficits in SCZ (Girard et al, ; Wilkins et al, ) by demonstrating the importance of strategy use.…”

“…Of note, these studies used different tasks to assess spatial and response learning. Thus, we recently extended these findings to demonstrate a within‐task differential deficit in allocentric, viewpoint‐independent versus viewpoint‐dependent memory in an SSD sample using both a neuropsychological task (Girard et al, ) and an analogous virtual‐reality task (Wilkins et al, ). Both tasks tested memory for object locations in a three‐dimensional spatial array.…”

“…In this regard, recent studies from our laboratory (Girard et al, ; Wilkins et al, ) and others (Hanlon et al, ; Weniger and Irle, ; Folley et al, ; Spieker et al, ) demonstrate robust deficits on tasks associated with hippocampal‐dependent learning of allocentric spatial relations among environmental cues in participants with schizophrenia‐spectrum disorders (SSDs). These findings are in contrast to relatively spared performance on tasks involving learning to navigate using a body‐centered egocentric approach, which involves learning a series of left and right turns or using a stimulus‐response approach, which involves identification of a single stimulus (i.e., identification of a landmark), connected with a learned chain of responses, such as left and right body turns.…”

Virtual reality in the assessment and treatment of psychosis: a systematic review of its utility, acceptability and effectiveness

“…The majority of the studies reviewed investigated the use of VR in the assessment of memory (Ku et al, 2003, Sorkin et al, 2006, Wilkins et al, 2013a, Wilkins et al, 2013b, Weniger and Irle, 2008, Spieker et al, 2012, Fajnerova et al, 2014, while others investigated the use of VR in assessing executive functioning (Josman et al, 2009), self perception (Landgraf et al, 2010, Synofzik et al, 2010, and reality distortion (Sorkin et al, 2008). Details of the reviewed studies are listed in Table 2.…”