Prefrontal cortex activation in task switching: an event-related fMRI study

When a switch between two tasks has to be carried out, performance is slowe r than in trials where the same task is performed repeatedly. This finding has been attributed to rime-consuming control processes required for task s witching. Previous results of other paradigms investigating cognitive contr ol processes suggested that prefrontal cortex is involved in executive cont rol. We used event-related fMRI to investigate prefrontal cortex involvemen t in task switching. Regions in the lateral prefrontal and premotor cortex bilaterally, the anterior insula bilaterally, the left intraparietal sulcus , the SMA/pre-SMA region and the cuneus/precuneus were activated by the tas k repetition condition and showed additional activation in the task switch condition. This confirmed the hypothesis that lateral prefrontal cortex is involved in task switching. However, the results also showed that this regi on is neither the only region involved in task switching nor a region speci fically involved in task switching. (C) 2000 Elsevier Science B.V. All righ ts reserved.