Remembering emotional stimuli re-instantiates valence coding voxel-patterns from visual and temporal cortex
Holly Bowen1, John Ksander2, Elizabeth Kensinger1; 1Boston College, 2Brandeis University
Retrieval involves the ability to reproduce information from the encoding episode. The visual cortex response during a prior experience may be re-instantiated at retrieval to support memory for visual details, particularly for negative memories which are more vivid (Bowen, Kark, & Kensinger, in press). In the current fMRI study, participants (N =16) intentionally encoded neutral words paired with a positive, neutral or negative stimuli. They then completed a memory test for those neutral words, in the absence of any emotional content. We identified regions that coded valence as a dimension (i.e. from positive to negative) while participants viewed emotional and neutral stimuli during study. Within those regions, we extracted the valenced stimuli’s voxel-pattern similarity structure. We then searched for re-instantiations of that similarity structure at retrieval, when emotional valence information was no longer present. In our results, visual and temporal cortex demonstrated valence coding during study; the extracted similarity structures showed re-instantiations during retrieval that were distributed across cortex. A large cluster in left temporal-occipital gyrus coded valence at study, with significantly correlated similarity structures at retrieval in the insula, superior temporal gyrus, parietal lobule, parahippocampal gyrus and fusiform. A cluster on the right in occipital gyrus also showed valence coding during study, and correlated with retrieval similarity structures in the precuneus, superior temporal and parahippocampal gyrus. These results indicate that valence representations encoded in visual and temporal cortex are reinstated during retrieval, even when cued by neutral memoranda.
Topic Area: LONG-TERM MEMORY: Episodic