Retrieval orientation and the control of recollection: an fMRI study

This study used event-related fMRI to examine the impact of the adoption of different retrieval orientations on the neural correlates of recollection. In each of two study-test blocks, participants encoded a mixed list of words and pictures and then performed a recognition memory task with words as the test items. In one block, the requirement was to respond positively to test items corresponding to studied words and to reject both new items and items corresponding to the studied pictures. In the other block, positive responses were made to test items corresponding to pictures, and items corresponding to words were classified along with the new items. On the basis of previous ERP findings, we predicted that in the word task, recollection-related effects would be found for target information only. This prediction was fulfilled. In both tasks, targets elicited the characteristic pattern of recollection-related activity. By contrast, nontargets elicited this pattern in the picture task, but not in the word task. Importantly, the left angular gyrus was among the regions demonstrating this dissociation of nontarget recollection effects according to retrieval orientation. The findings for the angular gyrus parallel prior findings for the "left-parietal" ERP old/new effect and add to the evidence that the effect reflects recollection-related neural activity originating in left ventral parietal cortex. Thus, the results converge with the previous ERP findings to suggest that the processing of retrieval cues can be constrained to prevent the retrieval of goal-irrelevant information.