Abnormal Scanning Patterns Based on Eye Movement Entropy in Early Psychosis
Dan Zhang1, Chunyan Ma1, Lihua Xu1
1Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
Summary
Individuals with first-episode schizophrenia (FES) and clinical high risk (CHR) for psychosis exhibit more random eye movement patterns than healthy controls (HCs). This eye-tracking finding may serve as an early psychosis biomarker.
Area of Science:
- Neuroscience
- Psychiatry
- Ophthalmology
Background:
- Abnormal scanning patterns are hypothesized in schizophrenia.
- Eye movement entropy quantifies randomness in gaze data.
Purpose of the Study:
- To quantify scanning randomness using entropy scores in first-episode schizophrenia (FES), clinical high risk (CHR) for psychosis, and healthy controls (HCs).
- To explore correlations between eye movement entropy and clinical/cognitive measures.
Main Methods:
- Eye-tracking was used on 86 FES, 124 CHR, and 115 HC participants viewing static images.
- Entropy scores were calculated from gaze data during image viewing.
- Cognitive assessments and symptom ratings were collected.
Main Results:
- FES and CHR groups showed higher overall entropy scores than HCs, evident within 2.5 seconds.
- CHR participants had higher entropy than HCs for low-meaning images.
- Early entropy scores correlated with negative symptoms (FES), attention (CHR), and processing speed (all groups).
Conclusions:
- Individuals with FES and CHR exhibit more random, less strategic visual scanning than HCs.
- Eye movement entropy correlates with clinical symptoms and neurocognition.
- Entropy may serve as a neurophysiological marker for early psychosis detection.
