任务难度对精神分裂症返回抑制时间进程的影响

摘要

目的 探讨任务难度对精神分裂症返回抑制时间进程的影响.方法 57例符合ICD-10精神分裂症诊断标准的患者(最后44例进入统计)接受线索-靶子实验.任务难度的3个水平分别为简单觉察、简单辨别和反应选择.靶子位置的2个水平分别为线索化位置和非线索化位置.线索开始呈现到靶子开始呈现的时间间隔(stimulus onset asynchrony,SOA)的3个水平分别为300 ms,700 ms,1 200 ms.记录被试的反应时和错误率.结果 (1)任务难度因素主效应显著(F=119.611,P=0.000),任务平均反应时依难度上升而逐渐延长；靶子刺激位置主效应显著(F=170.096,P=0.000),靶子在线索化位置的反应时比非线索化位置的反应时长；SOA主效应显著(F =152.124,P=0.000)；任务难度与靶子位置交互作用显著(F=24.718,P=0.000)；任务难度与SOA交互作用显著(F=4.023,P=0.003)；靶子位置与SOA交互作用显著(F =53.347,P=0.000)；任务难度、靶子位置与SOA的交互作用显著(F =2.890,P=0.023).(2)被试患者在简单觉察任务中返回抑制出现于300 ms至1 200 ms；在简单辨别任务及反应选择任务中返回抑制出现于700 ms至1 200 ms处.各SOA水平三组任务难度的IOR值差异均有统计学意义(各SOA水平三组P值均为0.000).结论 精神分裂症患者在三种任务中均发现存在返回抑制,在简单觉察任务中返回抑制出现于300 ms,简单辨别任务、反应选择任务中出现于700 ms.任务难度对精神分裂症返回抑制时间进程存在一定的影响.%Objective To investigate the relationship between the task difficulty and the time course of inhibition of return (IOR) in patients with schizophrenia. Methods A total of 57 patients met the criteria of schizophrenia in ICD-IO (44 cases were involved in result analysis) were assessed with the cue-target experiment. Three levels of different difficulty were set as simple detection, simple discrimination and response selection. The two target-locations were set as cued location and un-cued location. The three intervals corresponding to stimulus onset asynchronies (SOAs) were set at 300 ms, 700 ms and 1 200 ms. Reaction time and error rate were recorded. Results (1) There was significant main effect in factor of task difficulty ( F = 119. 611, P =0. 000) , reaction time increased gradually with the difficulty. There was significant main effect in target stimulate location ( F - 170. 096, P =0.000) , the reaction time in the cued location was longer than that in un-cued location. The main effect in SOA was significant ( F = 152. 124, P = 0. 000). There were significant interactions between task difficulty and target stimulus location (F =24. 718, P =0. 000) , between task difficulty and SOA (F=4.023, P=0.003) , between target location and SOA (F=53.347, P=0.000) , among task difficulty, SOA and target location (F = 2. 890, P = 0. 023). (2) IOR effect occurred at 300 ms to 1 200 ms in simple detection, and at 700 ms to 1 200 ms in simple discrimination and response selection. There was significant difference in IOR among the three groups with different task difficulty at each SOA level. Conclusion IOR existed in three different tasks in patients with schizophrenia. IOR effect appeared at 300ms in simple detection, at 700 ms in simple discrimination and response selection. Task difficulty has an effect on time course of IOR in patients with schizophrenia.