title: Facial Expressions Evoke Differential Neural Coupling in Macaques.
abstract: In humans and monkeys, face perception activates a distributed cortical network that includes extrastriate, limbic, and prefrontal regions. Within face-responsive regions, emotional faces evoke stronger responses than neutral faces ("valence effect"). We used fMRI and Dynamic Causal Modeling (DCM) to test the hypothesis that emotional faces differentially alter the functional coupling among face-responsive regions. Three monkeys viewed conspecific faces with neutral, threatening, fearful, and appeasing expressions. Using Bayesian model selection, various models of neural interactions between the posterior (TEO) and anterior (TE) portions of inferior temporal (IT) cortex, the amygdala, the orbitofrontal (OFC), and ventrolateral prefrontal cortex (VLPFC) were tested. The valence effect was mediated by feedback connections from the amygdala to TE and TEO, and feedback connections from VLPFC to the amygdala and TE. Emotional faces were associated with differential effective connectivity: Fearful faces evoked stronger modulations in the connections from the amygdala to TE and TEO; threatening faces evoked weaker modulations in the connections from the amygdala and VLPFC to TE; and appeasing faces evoked weaker modulations in the connection from VLPFC to the amygdala. Our results suggest dynamic alterations in neural coupling during the perception of behaviorally relevant facial expressions that are vital for social communication.
authors.affiliation: Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: INSERM, U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Lyon, France.
authors.forename: Fadila
authors.initials: F
authors.lastname: Hadj-Bouziane
authors.affiliation: Virginia Tech Carilion Research Institute, Roanoke, VA, USA.
authors.forename: Rosalyn
authors.initials: R
authors.lastname: Moran
authors.affiliation: Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD, USA.
authors.forename: Leslie G
authors.initials: LG
authors.lastname: Ungerleider
authors.affiliation: Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD, USA.|Department of Neuroradiology, University of Zurich, Zurich, Switzerland.
authors.forename: Alumit
authors.initials: A
authors.lastname: Ishai
mesh_terms: D000679:Amygdala / Q000502:physiology*; D000818:Animals; D001499:Bayes Theorem; D001931:Brain Mapping; D004644:Emotions / Q000502:physiology*; D005071:Evoked Potentials; D005149:Facial Expression; D008251:Macaca; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009434:Neural Pathways / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology*
keywords: DCM; connectivity; emotion; faces; primates