Eye Movement Indices in the Study of Depressive Disorder.

Abstract

Impaired cognition is one of the most common core symptoms of depressive disorder. Eye movement testing mainly reflects patients' cognitive functions, such as cognition, memory, attention, recognition, and recall. This type of testing has great potential to improve theories related to cognitive functioning in depressive episodes as well as potential in its clinical application.This study investigated whether eye movement indices of patients with unmedicated depressive disorder were abnormal or not, as well as the relationship between these indices and mental symptoms.Sixty patients with depressive disorder and sixty healthy controls (who were matched by gender, age and years of education) were recruited, and completed eye movement tests including three tasks: fixation task, saccade task and free-view task. The EyeLink desktop eye tracking system was employed to collect eye movement information, and analyze the eye movement indices of the three tasks between the two groups.(1) In the fixation task, compared to healthy controls, patients with depressive disorder showed more fixations, shorter fixation durations, more saccades and longer saccadic lengths; (2) In the saccade task, patients with depressive disorder showed longer anti-saccade latencies and smaller anti-saccade peak velocities; (3) In the free-view task, patients with depressive disorder showed fewer saccades and longer mean fixation durations; (4) Correlation analysis showed that there was a negative correlation between the pro-saccade amplitude and anxiety symptoms, and a positive correlation between the anti-saccade latency and anxiety symptoms. The depression symptoms were negatively correlated with fixation times, saccades, and saccadic paths respectively in the free-view task; while the mean fixation duration and depression symptoms showed a positive correlation.Compared to healthy controls, patients with depressive disorder showed significantly abnormal eye movement indices. In addition patients' anxiety and depression symptoms and eye movement indices were correlated. The pathological meaning of these phenomena deserve further exploration.认知受损是抑郁障碍常见的核心症状之一，眼 动（eye movement）检查主要反映患者的认识、记忆、 注意及再认、回忆比较等方面的认知功能，对研究抑 郁发作的认知功能有一定的理论和实践意义。.探究从未服药抑郁障碍患者眼动指标是否异常 以及这些指标与精神症状的关系。.纳入60 例抑郁障碍患者和性别、年龄及教育年 限匹配的60 例健康志愿者进行注视稳定性、跳视、自 由视图三个任务的眼球运动测试，应用EyeLink 桌面 式眼动仪收集眼动信息，分析比较两组三个任务的眼 动指标。.（1）注视稳定性任务中，相对于健康对照，抑 郁障碍患者在无干扰任务和有干扰任务中都呈现注视 次数增加、注视时间缩短、跳视次数增加、跳视路径 增加；（2）跳视任务中，抑郁障碍患者反向跳视潜伏 期延长，反向跳视峰速度减小；（3）自由视图任务中， 抑郁障碍患者扫视次数减少、平均注视时间延长；（4） 相关分析显示：朝向跳视幅度与焦虑症状呈负相关， 反向跳视潜伏期与焦虑症状呈正相关，自由视图任务 的注视次数、跳视次数、扫视路径与抑郁障碍症状呈 负相关，而平均注视时间与抑郁障碍症状呈正相关。.抑郁障碍患者较健康对照眼动指标存在明显异 常，且患者的焦虑、抑郁症状与眼动指标有相关性， 其病理生理学意义值得进一步探究。.