摘要
采用心理不应期研究范式,两个反应时实验检测了注意力资源分配的特征以及双任务的相互干扰机制。每次实验中,要求被试快速、相继对高低音辨别任务(T1)和Stroop任务(T2)作出选择性反应,T1和T2间采用6种不同的时间间隔(SOA),以系统考察不同SOA条件下两个任务的反应时走势。结果发现:(1)在重叠的双任务情境中,T1的中枢加工导致在T2上出现显著的PRP效应,T2的中枢反应选择对T1的反应选择和反应执行加工同样产生显著的影响。SOA以及T2的难度与复杂度实质性地影响了T1的反应选择和反应执行加工。(2)当两个任务同时需要进行中枢反应选择加工时,一个任务占用更多的注意资源将导致另一任务获得较少的注意资源,注意资源量的多寡直接决定了该任务的加工效率。(3)两个任务的加工相互影响、相互制约,这种制约机制不仅仅存在于中枢反应选择阶段,在反应执行阶段仍然存在。
In classic Psychological-Refractory-Period (PRP) paradigms, decreasing stimulus onset asynchronies (SOA) between the two tasks typically leads to increasing reaction time (RT2) to the second task (T2), but there is no influence on the reaction time (RT 1) to the first task (T1). Traditionally, the causes of this interference have been considered to be the limitations of attentional resources or the inherent nature of central bottleneck. The PRP effect has been extensively studied and has been traditionally explained by Pashler's response selection bottleneck (RSB) model, which proposes the processing of one task consists of three stages: (1) perceptual identification stage, which selects the task-relevant stimulus and extracts relevant attributes of said stimulus; (2) response selection (bottleneck) stage, which decides upon the .appropriate motor response; (3) response execution stage, which mainly executes explicit actions. Perceptual identification stage and response execution stage were generally assumed to operate in parallel with other cognitive processing, but the bottleneck stage was assumed to operate sequentially, meaning the stage of T2 response selection was often postponed until the corresponding stage of response selection of T1 had been completed. Tombu and Jolicoeur (2003) described the Central Capacity Sharing (CCS) model, assuming that the capacity limitations of the central stags were not all or none and the processing of both tasks occurred at reducing rates due to the sharing of limited common resources. Thus, the two models had different predictions to the RT1. The RSB model assumed that T1 could get access to the bottleneck as soon as required, so RT1 remained the same at all SOA, whereas the CCS model predicted that RT1 increased with decreasing SOA. The present research used a standard PRP paradigm, in two reaction time experiments, in which participants made speeded responses to both a tone (T1) and a Stroop task (T2), the two tasks arriving in rapid succession, and stimulus intervals presenting with varying SOA. The aim is to examine the predictions of the RSB model and the CCS model, in the meantime exploring the limitations of attentional resources and the interference mechanisms in dual-task situations. The results showed that: (1) In the overlapping tasks paradigm, when T1 was processing in the central bottleneck, the response to T2 was heavily affected by the T1, and the effect of PRP was significant. Varied SOA and different difficulty T2 information substantially influenced the response selection and response execution on T1. (2) When two tasks demanded central response selection processing at the same time, the one task using more available attention resources would lead to the other task using less attention resources. The amount of resources directly determined the processing efficiency of this task. (3) There existed interference in dual-task situations, this interference not only existed in the central response selection stage, but also existed in the stage of response execution. Taken together, RT1 effects may occur when central resources are shared between the Task 1 and Task 2 processes. These results provide strong support for CCS models of dual-task interference in the overlapping tasks paradigm.
出处
《心理学报》
CSSCI
CSCD
北大核心
2014年第2期174-184,共11页
Acta Psychologica Sinica
基金
教育部人文社会科学基金(项目号:09YJCXLX025)资助
关键词
双任务
心理不应期
反应选择
注意资源
STROOP任务
dual-task
psychological refractory period
response selection
attentional resource
Stroop task