Central versus peripheral determinants of patterned spike activity in rat vibrissa cortex during whisking

Fee, M. S., Mitra, P. P., Kleinfeld, D. (1997) Central versus peripheral determinants of patterned spike activity in rat vibrissa cortex during whisking. Journal of Neurophysiology, 78 (2). pp. 1144-1149. ISSN 00223077 (ISSN)

Abstract

We report on the relationship between single-unit activity in primary somatosensory vibrissa cortex of rat and the rhythmic movement of vibrissae. Animals were trained to whisk freely in air in search of food. Electromyographic (EMG) recordings from the mystatial pads served as a reference for the position of the vibrissae. A fast, oscillatory component in single-unit spike trains is correlated with vibrissa position within the whisk cycle. The phase of the correlation for different units is broadly distributed. A second, slowly varying component of spike activity correlates with the amplitude of the whisk cycle. For some units, the phase and amplitude correlations were of sufficient strength to allow the position of the whiskers to be accurately predicted from a single spike train. To determine whether the observed patterned spike activity was driven by motion of the vibrissae, as opposed to central pathways, we reversibly blocked the contralateral facial motor nerve during the behavioral task so that the rat whisked only on the ipsilateral side. The ipsilateral EMG served as a reliable reference signal. The fast, oscillatory component of the spike-EMG correlation disappears when the facial motor nerve is blocked. This implies that the position of vibrissae within a cycle is encoded through direct sensory activation. The slowly varying component of the spike-EMG correlation is unaffected by the block. This implies that the amplitude of whisking is likely to be mediated by corollary discharge. Our results suggest that motor cortex does not relay a reference signal to sensory cortex for positional information of the vibrissae during whisking.

Item Type: Paper
Uncontrolled Keywords: animal cell animal experiment animal tissue article electromyogram female hypothesis motor nerve nonhuman prediction priority journal rat reliability sensory cortex sensory deprivation spike wave vibrissa Action Potentials Animals Electromyography Movement Peripheral Nervous System Rats Somatosensory Cortex Vibrissae
Subjects: organism description > animal behavior
neurobiology
organism description > animal > mammal > rodent > rat
organism description > animal > mammal > rodent > rat
CSHL Authors:
Communities: CSHL labs > Mitra lab
Depositing User: CSHL Librarian
Date: 1997
Date Deposited: 04 Apr 2012 18:28
Last Modified: 10 Feb 2017 17:10
Related URLs:
URI: https://repository.cshl.edu/id/eprint/25831

Actions (login required)

Administrator's edit/view item Administrator's edit/view item