title: Convergence across tactile afferent types in primary and secondary somatosensory cortices.
abstract: Integration of information by convergence of inputs onto sensory cortical neurons is a requisite for processing higher-order stimulus features. Convergence across defined peripheral input classes has generally been thought to occur at levels beyond the primary sensory cortex, however recent work has shown that this does not hold for the convergence of slowly-adapting and rapidly-adapting inputs in primary somatosensory cortex. We have used a new analysis method for multi-unit recordings, to show convergence of inputs deriving from the rapidly-adapting and Pacinian channels in a proportion of neurons in both primary and secondary somatosensory cortex in the anaesthetised cat. We have validated this method using single-unit recordings. The secondary somatosensory cortex has a greater proportion of sites that show convergence of this type than primary somatosensory cortex. These findings support the hypothesis that the more complex features processed in higher cortical areas require a greater degree of convergence across input classes, but also shows that this convergence is apparent in the primary somatosensory cortex.
authors.affiliation: School of Medical Sciences, UNSW Australia, Sydney, Australia.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Carter
authors.affiliation: School of Medical Sciences, UNSW Australia, Sydney, Australia; Graduate School of Biomedical Engineering, UNSW Australia, Sydney, Australia; Sydney Medical School, University of Sydney, Sydney, Australia.
authors.forename: Spencer C
authors.initials: SC
authors.lastname: Chen
authors.affiliation: Graduate School of Biomedical Engineering, UNSW Australia, Sydney, Australia.
authors.forename: Nigel H
authors.initials: NH
authors.lastname: Lovell
authors.affiliation: School of Medical Sciences, UNSW Australia, Sydney, Australia.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Vickery
authors.affiliation: School of Medical Sciences, UNSW Australia, Sydney, Australia; School of Medicine, University of Western Sydney, Penrith, Australia.
authors.forename: John W
authors.initials: JW
authors.lastname: Morley
mesh_terms: D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D001931:Brain Mapping; D002415:Cats; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*; D014110:Touch / Q000502:physiology