Task Paradigms And Process Strategies Effects On Event-based Prospective Memory

The experiment material is26capital English letters,and subjects are college students.Task type.ongoing task (judge whether the second letter and the forth one is the same letter) and prospective task (decide if the second and the forth letter both are C). The two paradigm:dual-task and task-switch.And two process strategies:ongoing task priority and prospective task priority. Recording EEG by electrode cap with64conductions,and measure the ERP related to the time of fullfill a task by38college students,disscussing the change inside the brain with time in differernt paradigms,and find the differences in the congnitive processure between the two process priotities.According to the behavioural results:the task-switch is slower than dual-task on the RT,the PM priority condition is also slower than the ongoing condition, but on accuracy the task-switch is lower.The subjects adopt the restrain-switch strategy. Electrophysiological results.in the range of300-500ms time window,the prospective task lure an large amplitude wave(P400), and in the range of280-380ms time window, the task-switch induction an early minus component(N2),there is a difference with significance between the two task type.All of these results imply that different task types are dealed with different congnitive expresses,and using different strategies to process.Analysis of the ERP component which relavented to internal process revealed several following important conclusions.the prolonging of reacting time of task-switch is mainly because of the inhibitory extent on the execute of prospective task.The occupation of cognitive resource leads to insufficient attention and recognition resource to meet the needs of prospective task.In the strategy conditons there is only one difference between two terms by using the dual-task version,the only difference is strategy.In the prospective task priority term there also exist a restrain procedure,after the excution of the prospective task turn to the ongoing task.Do prospective task fistly or ongoing task fist induce the same ERP components,this illuminate a same internal procedure.