Reduced influence of perceptual context in schizophrenia: behavioral and neurophysiological evidence

Abstract

Background Accurate perception of visual contours is essential for seeing and differentiating objects in the environment. Both the ability to detect visual contours and the influence of perceptual context created by surrounding stimuli are diminished in people with schizophrenia (SCZ). The central aim of the present study was to better understand the biological underpinnings of impaired contour integration and weakened effects of perceptual context. Additionally, we sought to determine whether visual perceptual abnormalities reflect genetic factors in SCZ and are present in other severe mental disorders. Methods We examined behavioral data and event-related potentials (ERPs) collected during the perception of simple linear contours embedded in similar background stimuli in 27 patients with SCZ, 23 patients with bipolar disorder (BP), 23 first-degree relatives of SCZ, and 37 controls. Results SCZ exhibited impaired visual contour detection while BP exhibited intermediate performance. The orientation of neighboring stimuli (i.e. flankers) relative to the contour modulated perception across all groups, but SCZ exhibited weakened suppression by the perceptual context created by flankers. Late visual (occipital P2) and cognitive (centroparietal P3) neural responses showed group differences and flanker orientation effects, unlike earlier ERPs (occipital P1 and N1). Moreover, behavioral effects of flanker context on contour perception were correlated with modulation in P2 & P3 amplitudes. Conclusion In addition to replicating and extending findings of abnormal contour integration and visual context modulation in SCZ, we provide novel evidence that the abnormal use of perceptual context is associated with higher-order sensory and cognitive processes.

Self-reported perceptual aberrations in psychosis map to event-related potentials and semantic appraisals of objects.

“…Before performing the multilevel models, chi-square tests of independence were carried out on all ERP, FAOT, and personality measures to ensure the assumption of independence was not violated by family membership (e.g., two participants being siblings). Our past analyses show minimal to no contribution from family clusters (Pokorny et al, 2019; Silberschmidt & Sponheim, 2008). Likewise, none of the variables in the current sample violated independence; thus, family membership was not included as a random effect.…”

“…Individual differences in perceptual aberrations may be more sensitive than diagnostic groupings as suggested by a trend of higher perceptual absorption scores predicting more frequent object detection. Other studies have found individuals with schizophrenia have difficulty integrating discrete visual elements to perceive contours and closed simple objects (Pokorny et al, 2019;. An important difference is that FAOT consists of a semantically rich set of stimuli for which the participant determines whether there is meaning in the ambiguous stimulus, while perceptual integration tasks in nearly all studies require simple discrimination between two objects or discrete locations of contour.…”

Weakened untuned gain control is associated with schizophrenia while atypical orientation-tuned suppression depends on visual acuity

“…Given the criticisms of reliability and validity of categorical Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnoses and the shared features of schizophrenia and bipolar disorder ( Kotov, Krueger, Watson, Achenbach, Althoff, Bagby, Brown, Carpenter, Caspi, Clark, Eaton, Forbes, Forbush, Goldberg, Hasin, Hyman, Ivanova, Lynam, Markon, Miller, Moffitt, Morey, Mullins-Sweatt, Ormel, Patrick, Regier, Rescorla, Ruggero, Samuel, Sellborn, Simms, Skodol, Slade, South, Tackett, Waldman, Waszczuk, Widiger, Wright, & Zimmerman, 2017 ; Markon, Chmielewski, & Miller, 2011 ), understanding the degree to which visual processing impairments are reflective of categorical differences between disorders – as opposed to being reflective of a unified spectrum of psychotic experiences – may help clarify diagnostic and etiologic ambiguity. Furthermore, it is unclear whether such impairments are specific to the patient groups or extend to unaffected first-degree relatives ( Greenwood, Shutes-David, & Tsuang, 2019 ; Pokorny, Lano, Schallmo, Olman, & Sponheim, 2021 ; Schallmo, Sponheim, & Olman, 2013 ). Given the shared genetic predisposition among patients and their first-degree relatives, common visual processing impairments would suggest such impairments to be an underlying risk factor rather than simply a consequence of having the disorder.…”

Deficits in Auditory and Visual Sensory Discrimination Reflect a Genetic Liability for Psychosis and Predict Disruptions in Global Cognitive Functioning

“…Bipolar disorder patients have also shown auditory MMN deficits (17), as well as visual sensory processing deficits indexed by altered visual MMN/P300 (18), diminished P100 response on a "Go-No-Go" task (19), and diminished P300 on a contour perception task (20). Across psychotic disorders, these deficits appear to have downstream consequences for 'higher-order' cognition such as memory and executive control, and contribute to global cognitive impairments observed in these populations (1).…”