RT Journal Article
SR Electronic
T1 Dissociable medial temporal pathways for encoding emotional item and context information
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 248294
DO 10.1101/248294
A1 Maureen Ritchey
A1 Shao-Fang Wang
A1 Andrew P. Yonelinas
A1 Charan Ranganath
YR 2018
UL http://biorxiv.org/content/early/2018/01/15/248294.abstract
AB Emotional experiences are typically remembered with a greater sense of recollection than neutral experiences, but memory benefits for emotional items do not typically extend to their source contexts. Item and source memory have been attributed to different subregions of the medial temporal lobes (MTL), but it is unclear how emotional item recollection fits into existing models of MTL function and, in particular, what is the role of the hippocampus. To address these issues, we used high-resolution fMRI to examine MTL contributions to successful emotional item and context encoding. The results showed that emotional items were recollected more often than neutral items. Whereas amygdala and PRC activity supported the recollection advantage for emotional items, hippocampal and PHC activity predicted subsequent source memory for both types of items, reflecting a double dissociation between anterior and posterior MTL regions. We next tested whether amygdala activity during encoding modulated the relationship between MTL activity and subsequent memory outcomes. The amygdala and PRC played complementary roles in supporting subsequent item recollection, in that lower amygdala activity was associated with more memory dependence on PRC. In contrast, the amygdala and hippocampus played synergistic roles in supporting subsequent source memory, in that higher amygdala activity amplified the relation of hippocampal activity to subsequent source memory. The results suggest that emotion-related enhancements in item recollection are supported by an amygdala-perirhinal pathway, which is separable from the hippocampal pathway that binds items to their source context.