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

Affiliation

Okada KI(1)(2)(3), Miura K(4), Fujimoto M(4)(5), Morita K(6), Yoshida M(7)(8)(9), Yamamori H(4)(5)(10), Yasuda Y(4)(11)(12), Iwase M(5), Inagaki M(1)(2), Shinozaki T(2)(13), Fujita I(1)(2), Hashimoto R(14)(15)(16).
Author information:
(1)Graduate School of Frontier Biosciences, Osaka University, Osaka, 565-0871, Japan.
(2)Center for Information and Neural Networks
(CiNet), National Institute of Information and Communications Technology, and Osaka University, Osaka, 565-0871, Japan.
(3)Department of Physiology, Hokkaido University School of Medicine, Hokkaido, 060-8638, Japan.
(4)Department of Pathology of Mental Diseases, National Institute of Mental Health, National Center of Neurology and Psychiatry, Ogawa-Higashi 4-1-1, Kodaira, Tokyo, 187-8553, Japan.
(5)Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, 565-0871, Japan.
(6)Department of Rehabilitation, University of Tokyo Hospital, Tokyo, 113-8655, Japan.
(7)Department of Developmental Physiology, National Institute for Physiological Sciences, Aichi, 444-8585, Japan.
(8)School of Life Science, The Graduate University for Advanced Studies, Kanagawa, 240-0193, Japan.
(9)Center for Human Nature, Artificial Intelligence, and Neuroscience, Hokkaido University, Hokkaido, 060-0812, Japan.
(10)Japan Community Health Care Organization Osaka Hospital, Osaka, 553-0003, Japan.
(11)Life Grow Brilliant Mental Clinic, Medical Corporation Foster, Osaka, 530-0012, Japan.
(12)Molecular Research Center for Children's Mental Development, United Graduate School of Child Development, Osaka University, Osaka, 565-0871, Japan.
(13)Graduate School of Information Science and Technology, Osaka University, Osaka, 565-0871, Japan.
(14)Department of Pathology of Mental Diseases, National Institute of Mental Health, National Center of Neurology and Psychiatry, Ogawa-Higashi 4-1-1, Kodaira, Tokyo, 187-8553, Japan. [Email]
(15)Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, 565-0871, Japan. [Email]
(16)Molecular Research Center for Children's Mental Development, United Graduate School of Child Development, Osaka University, Osaka, 565-0871, Japan. [Email]

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.