Eye movement characteristics in male patients with deficit and non-deficit schizophrenia and their relationships with psychiatric symptoms and cognitive function

Abstract

Background The cognitive impairment pattern of deficit schizophrenia (DS) is centered on an impaired attention function. Previous studies have suggested that the exploratory eye movement (EEM) tests reflect attention deficits in patients with schizophrenia. However, no study has investigated the characteristics of eye movement in DS in the Chinese Han population. This study aimed to investigate the pattern of eye movement characteristics in DS patients and to examine whether eye movement characteristic is associated with serious negative symptoms and cognitive decline in this schizophrenia subtype. Methods A total of 86 male patients [37 DS and 49 non-deficit schizophrenia (NDS)] and 80 healthy controls (HC) participated in this study. Clinical symptoms were assessed using the Scale for the Assessment of Positive Symptoms (SAPS) and Scale for the Assessment of Negative Symptoms (SANS). Cognitive function was assessed using the Mattis Dementia Rating Scale (MDRS-2). Eye movement data of subjects were collected using an eye movement tracking analyzer. Results There were significant differences in the overall eye movement data and cognitive test scores among the three groups (all P < 0.001). Both DS and NDS schizophrenia subgroups showed more severe eye movement and cognitive impairment compared with the control group. The number of eye fixations (NEF), total of eye scanning length (TESL), and cognitive function in DS patients were significantly lower than those in NDS patients. The discriminant analysis (D score) was higher than that of the control group (P < 0.001). In the DS group, the inattention factor of SANS was negatively correlated with the attention factor (r = − 0.545, P = 0.001) and structure factor of cognitive (r = − 0.389, P = 0.023), the affective flattening factor of SANS was negatively correlated with TESL (r = − 0.353, P = 0.041) and initiation/retention factor of cognitive (r = − 0.376,P = 0.028). TESL was found to positively correlate with the MDRS-2 total score (r = 0.427, P = 0.012), attention factor (r = 0.354, P = 0.040), and memory factor (r = 0.349, P = 0.043) in the DS group, whereas the mean of eye scanning length (MESL) positively correlated with cognitive impairments in the NDS group. The negative symptoms showed no significant correlation with cognition in the NDS group. Conclusions Total of eye scanning length may be a characteristic eye movement symptom in DS patients, which is associated with serious negative symptoms and cognitive impairment in this schizophrenia subtype.

Differences in inflammatory marker profiles and cognitive functioning between deficit and nondeficit schizophrenia

“…For instance, Bryant et al reported a significant difference in white matter neurometabolic signatures between DS and NDS patients using single-voxel magnetic resonance spectroscopy technology (48). Zhang et al found that DS patients had different eye movement characteristics than NDS patients (49). Moreover, some previous studies also provided evidence suggesting an association between the DS subtype of schizophrenia and gene polymorphisms, including dopamine D2 receptor and catechol-O-methyltransferase (COMT) genes (50, 51).…”

“…Zhang et al. found that DS patients had different eye movement characteristics than NDS patients ( 49 ). Moreover, some previous studies also provided evidence suggesting an association between the DS subtype of schizophrenia and gene polymorphisms, including dopamine D2 receptor and catechol-O-methyltransferase (COMT) genes ( 50 , 51 ).…”

Exploring the impact of biological alterations in the superior thalamic radiations on exploratory eye movements in attenuated psychosis syndrome

“…Zhang et al. (2021) reported lower NEF values in patients with schizophrenia compared to healthy controls, with a further reduction in patients with schizophrenia with pronounced negative symptoms ( 48 ).…”

Lack of correlation between hippocampal substructure atrophy and attention dysfunction in deficit schizophrenia

“…It is still unclear, however, whether these cognitive deficits are pervasive or more severe within certain specific domains. In this regard, one recent study utilizing eye movement analysis suggested that the major deficits were related to attention 41 , while another suggested that DS patients had significantly impaired overall cognitive abilities, possibly associated with chronic neuroinflammation 42 . While the true extent of cognitive deficits in DS remains uncertain, the current study supports more pervasive deficits, at least in patients with a long (several decade) disease history.…”