title: Similarity to the self influences cortical recruitment during impression formation.
abstract: Prior work has shown that whether or not someone is similar to the self influences person memory--a type of self-reference effect for others. In this study, we were interested in understanding the neural regions supporting the generation of impressions and subsequent memory for targets who vary in similarity to the self. Participants underwent fMRI scanning while forming positive or negative impressions of face-behavior pairs. We tested participants' memory for their generated impressions and then back-sorted the impression trials (encoding) into different levels of self-similarity (high, medium, low) using a self-similarity posttest that came after recognition. Extending prior behavioral work, our data confirmed our hypothesis that memory would be highest for self-similar others and lowest for self-dissimilar others. Dorsal anterior cingulate cortex (dACC) activity increased with self-similarity (high > medium > low) to targets, regardless of later memory for them. An analysis of regions supporting impression memory revealed a double dissociation within medial temporal lobe regions: for similar others, amygdala recruitment supported memory, whereas for dissimilar others, hippocampal activation supported memory. These results suggest that self-similarity influences evaluation and memory for targets but also affects the underlying neural resources engaged when thinking about others who vary in self-similarity.
authors.affiliation: Department of Psychology, University of Illinois at Chicago, 1007 West Harrison Street (M/C 285), Chicago, IL, 60607-7137, USA. leshikar@uic.edu.|Department of Psychology, Brandeis University, Waltham, MA, USA. leshikar@uic.edu.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Leshikar
authors.affiliation: Department of Psychology, Brandeis University, Waltham, MA, USA.|Department of Psychological and Brain Sciences, Indiana University Bloomington, Bloomington, IN, USA.
authors.forename: Brittany S
authors.initials: BS
authors.lastname: Cassidy
authors.affiliation: Department of Psychology, Brandeis University, Waltham, MA, USA.
authors.forename: Angela H
authors.initials: AH
authors.lastname: Gutchess
mesh_terms: D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000502:physiology; D001931:Brain Mapping; D005145:Face / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*; D012919:Social Behavior; D013850:Thinking / Q000502:physiology*; D055815:Young Adult
keywords: Amygdala; Hippocampus; Impression formation; Medial prefrontal cortex; Memory; Self-reference effect; Self-similarity; fMRI