summary: Researchers have identified spatial and temporal abnormalities in spontaneous fixation saccades as potential biomarkers of cognitive and positive symptoms in schizophrenia. Researchers were able to determine schizophrenia with 85% accuracy by combining patient data of fixation eye movements recorded over 60 seconds with machine learning techniques. This finding suggests that fixation saccades may serve as a readily available complementary diagnostic tool for this condition.
sauce: Chinese Academy of Sciences
In a study published online, schizophrenia bulletinresearchers in the laboratory of Dr. Wang Wei, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, and Dr. Wang Jijun, Shanghai Center for Mental Health, Shanghai Jiao Tong University School of Medicine, and the team of Dr. Correlations between abnormalities and their positive and cognitive symptoms of schizophrenia suggest that fixed saccades are promising and readily available biomarkers for cognitive and positive symptoms and complementary diagnosis of schizophrenia doing.
Schizophrenia is a devastating heterogeneous psychotic disorder characterized by debilitating positive symptoms, negative symptoms, and cognitive impairment. Positive symptoms include hallucinations, delusions, confused speech, and strange behavior.
Negative symptoms constitute a lack of normal functioning. Cognitive impairment is observed in the majority of patients with schizophrenia involving many cognitive domains. These symptoms of schizophrenia are associated with alterations in the neurotransmitter system that cause structural and functional abnormalities in cortico-subcortical-cerebellar circuits.
Given the central importance of looking to humans, gaze is a fundamental pattern of behavior that enables people to gather information and guide decision-making. Microsaccades and large saccades (macrosaccades) occur spontaneously and frequently during fixation.
These fixed saccades are sensitive to structural and functional changes in cortico-subcortical-cerebellar circuits and are closely associated with cognitive processes. However, the performance of gaze saccades in patients with schizophrenia remains largely unexplored.
In this study, investigators performed 10 separate 6-second fixation trials recorded from 140 drug-naïve patients with first-episode schizophrenia and 160 age-matched healthy subjects. We analyzed the recorded gaze saccades.
They found that patients with schizophrenia exhibited significantly more vertical saccades and greater vertical misalignment of horizontal saccades. They also found that fixation saccades, particularly horizontal saccades, were longer in duration, faster in peak velocity and greater in amplitude in patients than in controls.
Careful measurements of cognitive performance in schizophrenic patients have shown that longer durations of horizontal saccades are associated with reduced cognitive performance, particularly reduced attention/vigilance and processing speed. Severe positive symptoms.
A simple machine-learning model classified patients and controls with 85% accuracy based only on 1-minute recorded fixation eye movements.
The findings of this study demonstrated that fixation saccades are a promising and readily available biomarker for cognitive and positive symptoms and complementary diagnosis of schizophrenia.
About this Schizophrenia Research News
author: press office
sauce: Chinese Academy of Sciences
contact: Press Office – Chinese Academy of Sciences
image: Image credited to Neuroscience News
Original research: closed access.
“Spatial and temporal abnormalities of spontaneous fixation saccades and their correlation with positive and cognitive symptoms in schizophrenia” by Xu Liu et al. schizophrenia bulletin
overview
Spatial and temporal abnormalities of spontaneous fixation saccades and their correlation with positive and cognitive symptoms in schizophrenia
Background and hypothesis
Fixation is a dynamic process in which microsaccades and macrosaccades occur spontaneously. These fixation saccades are sensitive to structural and functional changes in cortico-subcortical-cerebellar circuits. Given that dysfunctional cortico-subcortical-cerebellar circuits contribute to the cognitive and behavioral deficits in schizophrenia, patients with schizophrenia exhibit abnormal fixation saccades and these abnormalities are associated with clinical symptoms. I assumed you were.
research design
Saccades were evaluated from 140 drug-naïve patients with first-episode schizophrenia and 160 age-matched healthy controls during 10 separate trials of 6-second steady fixations. Recorded. Positive and negative symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). Cognition was assessed using Measurement and Treatment Studies to Improve Cognition in the Schizophrenia Consensus Cognitive Battery (MCCB).
Investigation result
Patients with schizophrenia showed more vertical fixation saccades than controls. This was reflected in more vertical saccades at patient angles of ~90° and greater vertical shifts in horizontal saccades at ~0° angles. Fixed saccades, especially horizontal saccades, showed longer duration, higher peak velocity and greater amplitude in patients. Furthermore, the greater the vertical shift of the horizontal saccades, the higher the patient’s total score and positive symptom score on his PANSS, and the longer the duration of the horizontal saccades, the greater the processing speed of the MCCB neurocognitive complex, attention/vigilance, and scores. was associated with a decline in Finally, based on these fixation eye movements alone, the K nearest neighbor model classified patients with 85% of his accuracy.
Conclusion:
Our results reveal spatial and temporal abnormalities in fixation saccades and suggest that fixation saccades are promising biomarkers of cognitive and positive symptoms, and diagnostic of schizophrenia.
