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Abstract: Episodic memory retrieval can be influenced by individuals' current goals, including those that are emotional in nature. Participants underwent an fMRI scan while reappraising, or changing the way they thought about aversive images they had previously encoded, to down-regulate (i.e., decrease), up-regulate (i.e., increase), or maintain the emotional intensity associated with their recall. A conjunction analysis between down- and up-regulation during the entire 12-s recall period revealed that both commonly activated reappraisal-related regions, particularly in the lateral and medial prefrontal cortex (PFC). However, when we analyzed a reappraisal instruction phase prior to recall and then divided the recall phase into the time when individuals were first searching for their memories and later elaborating on their details, we found that down- and up-regulation engaged greater neural activity at different time points. Up-regulation engaged greater PFC activity than down-regulation or maintenance during the reappraisal instruction phase. In contrast, down-regulation engaged greater lateral PFC activity as images were being searched for and retrieved. Maintaining the emotional intensity associated with the aversive images engaged similar regions to a greater extent than either reappraisal condition as participants elaborated on the details of the images they were holding in mind. Our findings suggest that down- and up-regulation engage similar neural regions during memory retrieval, but differ in the timing of this engagement. [Copyright &y& Elsevier]

Abstract: We examined the neural correlates of specific (i.e., unique to time and place) and general (i.e., extended in or repeated over time) autobiographical memories (AMs) during their initial construction and later elaboration phases. The construction and elaboration of specific and general events engaged a widely distributed set of regions previously associated with AM recall. Specific (vs. general) event construction preferentially engaged prefrontal and medial temporal lobe regions known to be critical for memory search and retrieval processes. General event elaboration was differentiated from specific event elaboration by extensive right-lateralized prefrontal cortex (PFC) activity. Interaction analyses confirmed that PFC activity was disproportionately engaged by specific AMs during construction, and general AMs during elaboration; a similar pattern was evident in regions of the left lateral temporal lobe. These neural differences between specific and general AM construction and elaboration were largely unrelated to reported differences in the level of detail recalled about each type of event. [Copyright &y& Elsevier]