Integration of representations is key to the enactment benefit: Insights from individuals with stroke lesions

Previous research has suggested that performing an action during encoding, related to the meaning of a target word (known as 'enactment'), benefits later memory retrieval relative to when the word is simply read. It has been suggested that enactment confers this memory benefit by promoting the formation of a multimodal memory trace through the integration of verbal and motoric representations, facilitated by the parietal lobe. More recent work has proposed that cognitive planning preceding the execution of enactment, via engagement of frontal lobe-based processes, is most critical for the memory benefit. Here, evidence for these two accounts was assessed by comparing memory in healthy controls relative to individuals with lesions to parietal or frontal brain areas. Frontal stroke participants and controls both showed significant enactment effects: Recall was better for words enacted at encoding relative to those that were silently read. In contrast, participants with parietal lesions did not show the effect. Results suggest that the integration of multimodal representations by parietal lobe-based processes is a critical step necessary to evoke the benefit of enactment on memory performance.