Impaired inhibition of return during free-viewing behaviour in patients with schizophrenia

Abstract

Schizophrenia affects various aspects of cognitive and behavioural functioning. Eye movement abnormalities are commonly observed in patients with schizophrenia (SZs). Here we examined whether such abnormalities reflect an anomaly in inhibition of return (IOR), the mechanism that inhibits orienting to previously fixated or attended locations. We analyzed spatiotemporal patterns of eye movement during free-viewing of visual images including natural scenes, geometrical patterns, and pseudorandom noise in SZs and healthy control participants (HCs). SZs made saccades to previously fixated locations more frequently than HCs. The time lapse from the preceding saccade was longer for return saccades than for forward saccades in both SZs and HCs, but the difference was smaller in SZs. SZs explored a smaller area than HCs. Generalized linear mixed-effect model analysis indicated that the frequent return saccades served to confine SZs’ visual exploration to localized regions. The higher probability of return saccades in SZs was related to cognitive decline after disease onset but not to the dose of prescribed antipsychotics. We conclude that SZs exhibited attenuated IOR under free-viewing conditions, which led to restricted scene scanning. IOR attenuation will be a useful clue for detecting impairment in attention/orienting control and accompanying cognitive decline in schizophrenia.

Eye tracking identifies biomarkers in α-synucleinopathies versus progressive supranuclear palsy

“…According to a recent study, patients with schizophrenia showed fewer fixations with longer duration and smaller and lower saccades during a free visual exploration compared to CTRL [ 63 ]. Silberg et al also showed that when patients with schizophrenia explore movies of real-life scenes, they had a strong centre bias behaviour and their gaze was independent of saliency based features of the movie [ 64 , 65 ]. Schizophrenic individuals explored a smaller area of the visual scene compared to CTRL [ 65 ].…”

“…Silberg et al also showed that when patients with schizophrenia explore movies of real-life scenes, they had a strong centre bias behaviour and their gaze was independent of saliency based features of the movie [ 64 , 65 ]. Schizophrenic individuals explored a smaller area of the visual scene compared to CTRL [ 65 ]. This pattern of results is similar to what we observed in all of our patient groups and may be indicative of general frontal cortex dysfunction.…”

Neural Correlates of Variation in Personal Space and Social Functioning in Schizophrenia and Healthy Individuals

“…The interpretation of these findings must be considered in light of several limitations of this study, such as its cross-sectional design, which limits the inferences that can be drawn from the mediation analysis. Also, in future work, measurements of the functioning of parietal-frontal circuits that are anatomically near to the network involved in PS regulation, such as those involved in eye movements 72–75 and gestures, 76 which are behaviors that are also affected in schizophrenia, 7 , 77–79 could be assessed in parallel to PS-related behaviors, to investigate the specificity of the effects observed in the current study. In addition, other processes that may contribute to the ability to distinguish the self from others and from the surrounding environment could be measured, since a wide range of abnormalities in this overall domain have been observed in psychotic individuals.…”

Aberrant visual salience in participants with schizophrenia during free-viewing of natural images

“…Recently, our research group reported the finding that inhibition-of-return is impaired in SZs (Okada et al, 2021). This might raise the question of whether return saccades toward salient stimuli are more frequent in schizophrenia (Figure S1A).…”