title: Others' Sheer Presence Boosts Brain Activity in the Attention (But Not the Motivation) Network.
abstract: The sheer presence of another member of the same species affects performance, sometimes impeding it, sometimes enhancing it. For well-learned tasks, the effect is generally positive. This fundamental form of social influence, known as social facilitation, concerns human as well as nonhuman animals and affects many behaviors from food consumption to cognition. In psychology, this phenomenon has been known for over a century. Yet, its underlying mechanism (motivation or attention) remains debated, its relationship to stress unclear, and its neural substrates unknown. To address these issues, we investigated the behavioral, neuronal, and endocrinological markers of social facilitation in monkeys trained to touch images to obtain rewards. When another animal was present, performance was enhanced, but testing-induced stress (i.e., plasma cortisol elevation) was unchanged, as was metabolic activity in the brain motivation network. Rather, task-related activity in the (right) attention frontoparietal network encompassing the lateral prefrontal cortex, ventral premotor cortex, frontal eye field, and intraparietal sulcus was increased when another individual was present compared with when animals were tested alone. These results establish the very first link between the behavioral enhancement produced by the mere presence of a peer and an increase of metabolic activity in those brain structures underpinning attention.
authors: INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, ImpAct Team, Lyon F-69000, France.|University of Lyon, Lyon F-69000, France.|Institut de Médecine Environnementale, Paris, France.
authors: Elisabetta
authors: E
authors: Monfardini
authors: CERMEP-Imagerie du Vivant, Lyon, France.
authors: Jérôme
authors: J
authors: Redouté
authors: INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, ImpAct Team, Lyon F-69000, France.|University of Lyon, Lyon F-69000, France.
authors: Fadila
authors: F
authors: Hadj-Bouziane
authors: INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, ImpAct Team, Lyon F-69000, France.|University of Lyon, Lyon F-69000, France.
authors: Clément
authors: C
authors: Hynaux
authors: Institut de Médecine Environnementale, Paris, France.
authors: Jacques
authors: J
authors: Fradin
authors: Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), UMR 7290-LPC and Fédération de Recherche 3C, Marseille, France.
authors: Pascal
authors: P
authors: Huguet
authors: CERMEP-Imagerie du Vivant, Lyon, France.
authors: Nicolas
authors: N
authors: Costes
authors: INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, ImpAct Team, Lyon F-69000, France.|University of Lyon, Lyon F-69000, France.
authors: Martine
authors: M
authors: Meunier
mesh_terms: D000818:Animals; D001132:Arm / Q000502:physiology; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D019788:Fluorodeoxyglucose F18; D007839:Functional Laterality; D006854:Hydrocortisone / Q000097:blood; D008253:Macaca mulatta; D009042:Motivation / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012919:Social Behavior; D013315:Stress, Psychological / Q000503:physiopathology
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D006854:Hydrocortisone
keywords: FDG-PET; audience; macaque monkeys; social facilitation; social presence