Altered attentive bias towards interpersonal communication information across phases of schizophrenia: an eye-tracking study

Background Eye movement abnormality in schizophrenia has been studied for several decades. However, patient differences in eye movements across phases of schizophrenia from eye-tracking studies have not been well documented. Aims This pilot study used eye-tracking technology to investigate attentive bias towards interpersonal communication information across different clinical phases of schizophrenia. Methods This study included 78 persons at clinical high risk (CHR) for schizophrenia, 68 first-episode (FEZ) patients, and 39 chronically ill patients from the Shanghai At Risk for Psychosis Extending Project (SHARP Extending cohort) as well as 74 healthy controls (HCs). The experiment was an unguided-viewing task composed of 24 trials showing three types of pictures which varied in the degree of interpersonal communication. Type 1 was a scenery picture without people, type 2 was a picture with four people not communicating, and type 3 was a picture with four people communicating. We used two measures: (1) initial fixation duration and (2) total fixation duration. Results A ratio for both measures was calculated between measures for pictures with more or less interpersonal communication. The ratio of initial fixation duration for pictures with people communicating versus pictures with people not communicating was lowest in chronically ill patients (0.13 (0.34))compared with HCs (0.31 (0.36)), FEZ patients (0.31 (0.46)), and CHR patients (0.36 (0.42)). The difference in the ratios of initial fixation duration for type 2 and type 3 pictures was also significant for female participants (HCs vs chronically ill patients, t=2.706, p=0.009; CHR patients vs chronically ill patients, t=4.079, p