title: Stability of Sensory Topographies in Adult Cortex.
abstract: Textbooks teach us that the removal of sensory input to sensory cortex, for example, following arm amputation, results in massive reorganisation in the adult brain. In this opinion article, we critically examine evidence for functional reorganisation of sensory cortical representations, focusing on the sequelae of arm amputation on somatosensory topographies. Based on literature from human and non-human primates, we conclude that the cortical representation of the limb remains remarkably stable despite the loss of its main peripheral input. Furthermore, the purportedly massive reorganisation results primarily from the formation or potentiation of new pathways in subcortical structures and does not produce novel functional sensory representations. We discuss the implications of the stability of sensory representations on the development of upper-limb neuroprostheses.
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford OX39DU, UK; Institute of Cognitive Neuroscience, University College London, London WC1N 3AR, UK. Electronic address: t.makin@ucl.ac.uk.
authors.forename: Tamar R
authors.initials: TR
authors.lastname: Makin
authors.affiliation: Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL, USA.
authors.forename: Sliman J
authors.initials: SJ
authors.lastname: Bensmaia
mesh_terms: D000328:Adult; D000671:Amputation, Surgical; D000818:Animals; D001132:Arm / Q000294:innervation / Q000601:surgery; D001931:Brain Mapping; D006801:Humans; D009473:Neuronal Plasticity / Q000502:physiology*; D013003:Somatosensory Cortex / Q000503:physiopathology*