Eye movement study on facial emotion processing in patients with Alzheimer's disease / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To explore the effect of visual processing patterns on emotional face processing in patients with Alzheimer's disease (AD).Methods:From June 2020 to August 2021, twenty-two AD patients (AD group) who met the conditions of this study were selected from the memory impairment clinic of the First Affiliated Hospital of Anhui Medical University, and demographically matched twenty-one elderly healthy people (control group) were selected from the patients' family members and community residents. The two groups of subjects performed emotional face visual scanning and facial recognition experiments after completing the evaluation of the cognitive scale and eye movement data were recorded in the emotional face visual scanning task. Statistical analysis of the obtained results was performed using SPSS 23.0 Windows version software. The data that conformed to the normal distribution were tested by independent samples t-test and variance analysis, and the data that did not conform to the normal distribution were tested by nonparametric test. Results:(1)In the emotional face recognition task, the total accuracy of facial emotion recognition of AD patients(0.52(0.42, 0.59)) was lower than that of the normal control group(0.67(0.64, 0.69)), and the difference was statistically significant( Z=-4.023, P<0.01), which was mainly manifested in recognizing complex facial emotion. (2) In the emotional face visual processing task, the saccade count ((1.96±0.97), (2.50±0.44)), fixation count ((3.93±2.58), (6.37±2.08))and fixation time ((1 205.89±727.32)s, (1 761.38±525.54)s)of AD patients were lower than those of the control group( t=-2.314, -3.402, -2.880, all P<0.05), and the surrounding facial fixation time (384.95 (276.51, 587.78)s, 276.06 (190.03, 384.55)s) was higher than that of the control group( Z=-2.478, P=0.013). Patients with AD had a lower fixation count than that in the control group on the eye area of surprise ((3.76±2.90), (6.25±2.19)), anger ((4.48±2.72), (7.06±2.55)) and disgust ((4.10±2.45), (6.67±2.45)), and the differences were statistically significant ( t=-3.164, -3.207, -3.436, all P<0.05). Patients with AD had a lower fixation time than those of the control group on the eye area of surprise ((1 150.26±753.22)s, (1 779.91±551.66)s), angry ((1 430.85±869.52)s, (1 944.51±612.63)s) and disgust ((1 266.14±765.67)s, (1 898.33±676.02)s), and the differences were statistically significant ( t=-3.115, -2.247, -2.865, all P<0.05). (3) Spearman correlation analysis showed that the accuracy of overall emotional face recognition was positively correlated with the fixation time in the eye area in AD patients ( r=0.429, P<0.05). Conclusion:The impaired visual processing of AD patients causes emotional face recognition disorders. Therefore, AD patients have different visual processing patterns in emotional face processing than age-matched normal controls, mainly manifested as the decreased fixation on the eye area.