DOI: 10.5061/dryad.nk98sf7q7
title: Data from: Area 2 of primary somatosensory cortex encodes kinematics of the whole arm

description: Proprioception, the sense of body position, movement, and associated
 forces, remains poorly understood, despite its critical role in movement.
 Most studies of area 2, a proprioceptive area of somatosensory cortex,
 have simply compared neurons' activities to the movement of the hand
 through space. By using motion tracking, we sought to elaborate this
 relationship by characterizing how area 2 activity relates to whole arm
 movements. We found that a whole-arm model, unlike classic models,
 successfully predicted how features of neural activity changed as monkeys
 reached to targets in two workspaces. However, when we then evaluated this
 whole-arm model across active and passive movements, we found that many
 neurons did not consistently represent the whole arm over both conditions.
 These results suggest that 1) neural activity in area 2 includes
 representation of the whole arm during reaching and 2) many of these
 neurons represented limb state differently during active and passive
 movements.
description: For
 full methodological information, see:
 [1]
 Chowdhury, R.H., Glaser, J.I., Miller, L.E. Area 2 of primary
 somatosensory cortex encodes kinematics of the whole arm.
 <em>eLife</em> (2019) doi:
 10.7554/eLife.48198
description: This data
 set includes behavioral recordings and extracellular neural recordings
 from area 2 of primary somatosensory cortex of Rhesus macaques during two
 separate reaching experiments. Raeed Chowdhury collected and processed the
 data in the laboratory of Lee Miller for use in Chowdhury et al. 2019
 (accepted in <i>eLife</i> as of 12/2019), which characterized
 how area 2 neurons represent reaching movements. Results and methodology
 from these experiments are described in
 [1]. In both
 experiments, monkeys controlled a cursor on a screen using a two link,
 planar manipulandum. In the first experiment, from which we include eight
 total sessions, monkeys reached to sequential, visually presented targets
 in one of two workspaces: one near the body on the contralateral side to
 the reaching arm and one far from the body on the ipsilateral side. In the
 second experiment, from which we include four total sessions, monkeys
 performed a simple center-out task, where on some random trials during the
 center-hold period, the manipulandum applied a perturbation to the
 monkey’s hand. During these reaching tasks, we tracked the locations of
 ten markers on the monkey’s arm, used to estimate joint angles and muscle
 lengths during the behavioral experiments. In addition to the behavioral
 data, we collected neural data from area 2 using Blackrock Utah
 multielectrode arrays, yielding ~100 channels of extracellular recordings
 per monkey. Recordings from these channels were thresholded online to
 detect spikes, which were sorted offline into putative single
 units. In addition to the data from
 these experiments, we have also included data from several sensory mapping
 sessions with the three monkeys, where we characterized the sensory
 receptive fields of several electrodes on the arrays. Analysis
 code used to produce figures for [1] provides useful examples for how to
 work with this dataset. See https://github.com/raeedcho/s1-kinematics.git for code and readme. If you publish any work using the data, please cite the publication above ([1] Chowdhury et. al, 2019) and also cite this data set.