Pictorial size perception in schizophrenia

Maria Lúcia De Bustamante Simas,Flora Silva Teixeira,Aline Mendes Lacerda,Cecília Coimbra Da Silva Raposo,Ana Cristina Taunay Maranhão,Georgia Mônica Marque De Menezes,Carlos Henrique Resende Freire

doi:10.1186/s41155-021-00201-z

Maria Lúcia De Bustamante Simas, Flora Silva Teixeira + Show 5 more

Open Access

https://doi.org/10.1186/s41155-021-00201-z

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Abstract

In this study, we compared visual pictorial size perception between healthy volunteers (CG) and an experimental group (EG) of people diagnosed with schizophrenia. We have been using paintings by Salvador Dalí and Rorschach plates to estimate visual pictorial size perception. In this transversal, ex post facto, and quasi-experimental study, we observed differences between EG and CG. Schizophrenic in-patients perceived sizes about 1.3-fold greater than healthy volunteers (p=0.006), implying that pictorial size perception is altered in some way in schizophrenia. Considering the present and previous results, this measurement of diameter size of first pictorial perception may be a useful estimate of some aspects of perceptual alterations that may be associated with psychotic symptoms in prodromal and acute schizophrenic episodes and other related mental states. Eventually, this may help in preventing people from evolving to acute episodes.

Highlights

Evidence that sensory processes are altered in schizophrenic patients is a widely accepted finding, the exact nature and impact of such alterations are not fully understood
The only works indirectly related to our study we found in the literature were about size perception of the Müller-Lyer and Ponzo illusions (King et al, 2017; Pessoa et al, 2008; Shoshina et al, 2011; Weckowics & Witney, 1960), or about altered pictorial perception, in this case, the perception of pareidolias, in Lewis-body dementia and/or Parkinson disease (Mamiyaet al., 2016; Uchiyama et al, 2012; Uchiyama et al, 2015; Yoko et al, 2014)
We argue that schizophrenic patients present disrupted pictorial size perception showing a tendency towards the perception of large magnitudes compatible with high sensitivity to extremely low fundamental spatial frequencies

Summary

Introduction

Evidence that sensory processes are altered in schizophrenic patients is a widely accepted finding, the exact nature and impact of such alterations are not fully understood. The only works indirectly related to our study we found in the literature were about size perception of the Müller-Lyer and Ponzo illusions (King et al, 2017; Pessoa et al, 2008; Shoshina et al, 2011; Weckowics & Witney, 1960), or about altered pictorial perception, in this case, the perception of pareidolias, in Lewis-body dementia and/or Parkinson disease (Mamiyaet al., 2016; Uchiyama et al, 2012; Uchiyama et al, 2015; Yoko et al, 2014). Weckowics and Witney (1960) found that schizophrenics showed larger Müller-Lyer illusion effects than controls, but their group of non-schizophrenic psychiatric patients provided responses consistent with the perception of larger magnitude effects than controls but, in turn, lower magnitudes than schizophrenics. In 2008, Pessoa et al.. suggested the use of the Müller-Lyer illusion for screening schizophrenic patients based on an animal model

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