心理不应期(PRP)效应发生在两个需要单独反应的刺激依次出现时,特别是它们之间的时间间隔短且可变。疲劳是一种次优的心理生理状态,会导致策略的变化。近年来,许多研究已经研究了经颅直流电刺激(tDCS)对运动控制的影响。本研究旨在探讨两种tDCS方法的效果,阳极和阴极,在非疲劳和精神疲劳条件下,在10种不同的刺激开始异步(SOA)条件下对PRP进行研究。参与者涉及39名19至25岁的男性大学生。在预测试,在非疲劳和精神疲劳两种情况下使用PRP测量工具进行评估.精神疲劳是由30分钟的Stroop任务引起的。测试包括具有不同SOA的两个刺激(50、75、100、150、300、400、600、900、1200和1500ms)。第一个是有三个选择的视觉刺激(字母A,B,andC).在随机SOA之后,第二个刺激,有三种选择的视觉刺激(红色,黄色,和蓝色),被介绍了。随后,参与者被随机分配到阳极,Cathodal,和假刺激组,并接受连续四次tDCS刺激。在阳极和阴极刺激组中,每次对PLPFC区域施加20分钟的tDCS刺激,而在假组里,刺激是人为施加的。所有参与者都使用与预测测试阶段相同的测量工具进行评估。在最后一次刺激后一天的测试后阶段,在四天后的后续阶段。推理统计包括混合方差分析,单向方差分析,独立,和依赖的t检验。研究结果表明,在较低的SOA下,对第二次刺激的响应时间更长。然而,两组在这方面没有显著差异.此外,疲劳和非疲劳条件对第二次刺激的响应时间没有显着差异,或群体之间。因此,tDCS无显著影响。心理不应期精神疲劳与非疲劳状态存在显著差异。此外,在较低的SOA,PRP比更高的SOA更长。在疲劳的情况下,在较高的SOA下,主动刺激组(阳极和阴极)的表现优于假刺激组。考虑到不同SOA对两种刺激的反应差异,响应的一些中心方面可以同时平行。疲劳也影响并行处理。本研究支持PRP中的响应整合现象,预测随着两种刺激的呈现之间的间隔增加,对第一刺激的响应时间将增加。这一发现与瓶颈模型相矛盾。在这项研究中,发现阴极和阳极tDCS对第二次刺激和PRP的响应时间的有效性非常小。
The psychological refractory period (PRP) effect occurs when two stimuli that require separate responses are presented sequentially, particularly with a short and variable time interval between them. Fatigue is a suboptimal psycho-physiological state that leads to changes in strategies. In recent years, numerous studies have investigated the effects of transcranial direct current stimulation (tDCS) on motor control. The present study aimed to investigate the effects of two tDCS methods, anodal and cathodal, on PRP in ten different conditions of stimulus-onset asynchronies (SOAs) under non-fatigue and mental fatigue conditions. The participants involved 39 male university students aged 19 to 25 years. In the pre-test, they were assessed using the PRP measurement tool under both non-fatigue and mental fatigue conditions. The mental fatigue was induced by a 30-min Stroop task. The test consisted of two stimuli with different SOAs (50, 75, 100, 150, 300, 400, 600, 900, 1200, and 1500 ms). The first was a visual stimulus with three choices (letters A, B, and C). After a random SOA, the second stimulus, a visual stimulus with three choices (colors red, yellow, and blue), was presented. Subsequently, participants were randomly assigned to the anodal, cathodal, and sham stimulation groups and underwent four consecutive sessions of tDCS stimulation. In the anodal and cathodal stimulation groups, 20 min of tDCS stimulation were applied to the PLPFC area in each session, while in the sham group, the stimulation was artificially applied. All participants were assessed using the same measurement tools as in the pre-test phase, in a post-test phase one day after the last stimulation session, and in a follow-up phase four days after that. Inferential statistics include mixed ANOVA, one-way ANOVA, independent, and dependent t-tests. The findings indicated that the response time to the second stimulus was longer at lower SOAs. However, there was no significant difference between the groups in this regard. Additionally, there was no significant difference in response time to the second stimulus between the fatigue and non-fatigue conditions, or between the groups. Therefore, tDCS had no significant effect. There was a significant difference between mental fatigue and non-fatigue conditions in the psychological refractory period. Moreover, at lower SOAs, the PRP was longer than at higher SOAs. In conditions of fatigue, the active stimulation groups (anodal and cathodal) performed better than the sham stimulation group at higher SOAs. Considering the difference in response to both stimuli at different SOAs, some central aspects of the response can be simultaneously parallel. Fatigue also affects parallel processing. This study supports the response integration phenomenon in PRP, which predicts that there will be an increase in response time to the first stimulus as the interval between the presentation of the two stimuli increases. This finding contradicts the bottleneck model. In this study, the effectiveness of cathodal and anodal tDCS on response time to the second stimulus and PRP was found to be very small.