title: Different Patterns of Cortical Inputs to Subregions of the Primary Motor Cortex Hand Representation in Cebus apella.
abstract: The primary motor cortex (M1) plays an essential role in the control of hand movements in primates and is part of a complex cortical sensorimotor network involving multiple premotor and parietal areas. In a previous study in squirrel monkeys, we found that the ventral premotor cortex (PMv) projected mainly to 3 regions within the M1 forearm representation [rostro-medial (RM), rostro-lateral (RL), and caudo-lateral (CL)] with very few caudo-medial (CM) projections. These results suggest that projections from premotor areas to M1 are not uniform, but rather segregated into subregions. The goal of the present work was to study how inputs from diverse areas of the ipsilateral cortical network are organized within the M1 hand representation. In Cebus apella, different retrograde neuroanatomical tracers were injected in 4 subregions of the hand area of M1 (RM, RL, CM, and CL). We found a different pattern of input to each subregion of M1. RM receives inputs predominantly from dorsal premotor cortex, RL from PMv, CM from area 5, and CL from area 2. These results support that the M1 hand representation is composed of several subregions, each part of a unique cortical network.
authors.affiliation: Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.
authors.forename: Melvin
authors.initials: M
authors.lastname: Dea
authors.affiliation: Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, Québec, Canada.
authors.forename: Adjia
authors.initials: A
authors.lastname: Hamadjida
authors.affiliation: Psychosocial Research Division, Douglas Institute Research Centre, Verdun, QC, Canada.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Elgbeili
authors.affiliation: Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.
authors.forename: Stephan
authors.initials: S
authors.lastname: Quessy
authors.affiliation: Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, Québec, Canada.
authors.forename: Numa
authors.initials: N
authors.lastname: Dancause
mesh_terms: D000818:Animals; D002428:Cebus; D004558:Electric Stimulation; D005260:Female; D006225:Hand / Q000294:innervation* / Q000502:physiology*; D009044:Motor Cortex / Q000166:cytology* / Q000502:physiology*; D009434:Neural Pathways / Q000166:cytology / Q000502:physiology; D056347:Neuroanatomical Tract-Tracing Techniques; D066191:Sensorimotor Cortex / Q000166:cytology / Q000502:physiology; D055698:Touch Perception / Q000502:physiology
keywords: connections; hand; motor cortex; network; parietal cortex