准备时间和预先信息对任务切换的影响

Effects of Preparation Time and Foreknowledge on Task Switching

两个实验采用任务线索范式，考察了准备时间和预先信息对任务切换的影响。实验1的准备时间为可预测，实验2的为不可预测，以考察准备时间的可预测性对任务切换的影响。以被试执行重复任务、切到任务和切离任务的正确反应时为主要指标，结果：（1）在准备时间可预测和不可预测两种条件下，准备时间和预先信息之间存在显著交互作用。在可预测条件中，重复和切到任务的反应时随着准备时间的增加而减少，但切到代价无显著变化，切离任务的反应时不受准备时间的影响，切离代价表现出反准备效应；不可预测条件下，三种任务的反应时都随着准备时间的增加而减少，但是切到和切离代价表现出反准备效应；（2）切离任务的反应时和代价显著高于切到任务的反应时和代价；（3）在这两种条件下，都没有出现切换代价的准备效应。

Recently， Task switching is an important paradigm for studying executive control. Switching cost refer to the performance differences in task-switch and task-repeat trials. Many issues and problems need further exploration. Theoretically， there is disagreement as to whether switch costs actually represents the task-set reconfiguration or the task-set inertia. Many studies have found that a prolonged preparation time reduces switch costs， which has been attributed to a task set reconfiguration pr