title: Face-selective neurons maintain consistent visual responses across months.
abstract: Face perception in both humans and monkeys is thought to depend on neurons clustered in discrete, specialized brain regions. Because primates are frequently called upon to recognize and remember new individuals, the neuronal representation of faces in the brain might be expected to change over time. The functional properties of neurons in behaving animals are typically assessed over time periods ranging from minutes to hours, which amounts to a snapshot compared to a lifespan of a neuron. It therefore remains unclear how neuronal properties observed on a given day predict that same neuron's activity months or years later. Here we show that the macaque inferotemporal cortex contains face-selective cells that show virtually no change in their patterns of visual responses over time periods as long as one year. Using chronically implanted microwire electrodes guided by functional MRI targeting, we obtained distinct profiles of selectivity for face and nonface stimuli that served as fingerprints for individual neurons in the anterior fundus (AF) face patch within the superior temporal sulcus. Longitudinal tracking over a series of daily recording sessions revealed that face-selective neurons maintain consistent visual response profiles across months-long time spans despite the influence of ongoing daily experience. We propose that neurons in the AF face patch are specialized for aspects of face perception that demand stability as opposed to plasticity.
authors.affiliation: Section on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892; mcmahond@mail.nih.gov.
authors.forename: David B T
authors.initials: DB
authors.lastname: McMahon
authors.affiliation: Section on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892;Department of Biology, University of Maryland, College Park, MD 20742;
authors.forename: Adam P
authors.initials: AP
authors.lastname: Jones
authors.affiliation: Institute of Higher Nervous Activity and Neurophysiology, Moscow 117485, Russia; and.
authors.forename: Igor V
authors.initials: IV
authors.lastname: Bondar
authors.affiliation: Section on Cognitive Neurophysiology and Imaging, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892;Neurophysiology Imaging Facility, National Institute of Mental Health, National Eye Institute, and National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892.
authors.forename: David A
authors.initials: DA
authors.lastname: Leopold
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology; D004567:Electrodes, Implanted; D005145:Face; D005260:Female; D005556:Form Perception / Q000502:physiology*; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D009473:Neuronal Plasticity / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D012919:Social Behavior
keywords: fMRI; physiology; vision