Isometric force-related activity in sensorimotor cortex measured with functional MRI. Academic Article uri icon

Overview

abstract

  • Isometric force-related functional magnetic resonance imaging (fMRI) signals from primary sensorimotor cortex were investigated by imaging during a sustained finger flexion task at a number of force levels related to maximum voluntary contraction. With increasing levels of force, there was an increase in the extent along the central sulcus from which a fMRI signal could be detected and an increase in the summed signal across voxels, but these parameters were related in such a way that the signal from each voxel was similar for each level of force. The results suggest that increased neuronal firing and recruitment of corticomotor cells associated with increased voluntary isometric effort are reflected in an expansion of a relatively constant fMRI signal over a greater volume of cortex, rather than an increase in the magnitude of the response in a particular circumscribed region, possibly due to perfusion of an increase in oxygen-enriched blood over a wider region of the cortex.

publication date

  • July 1, 1998

Research

keywords

  • Isometric Contraction
  • Magnetic Resonance Imaging
  • Motor Cortex
  • Somatosensory Cortex

Identity

Scopus Document Identifier

  • 0031801516

Digital Object Identifier (DOI)

  • 10.1007/s002210050437

PubMed ID

  • 9698191

Additional Document Info

volume

  • 121

issue

  • 1