Related Experiment Video
Updated: Jun 21, 2026
06:31
Automated Gait Analysis to Assess Functional Recovery in Rodents with Peripheral Nerve or Spinal Cord Contusion Injury
Published on: October 6, 2020
Ipsilateral cortical fMRI responses after peripheral nerve damage in rats reflect increased interneuron activity
Galit Pelled1, Debra A Bergstrom, Patrick L Tierney
1Laboratory of Functional and Molecular Imaging and Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. pelled@kennedykrieger.org
Summary
Peripheral nerve injury causes brain region reorganization. In denervated rats, increased brain activity in the somatosensory cortex (SI) was linked to interneuron activity, not local field potentials.
Area of Science:
- Neuroscience
- Neurophysiology
- Somatosensory System Research
Background:
- Peripheral nerve injury can lead to significant changes in the central nervous system.
- The primary somatosensory cortex (SI) is known to reorganize following deafferentation.
Purpose of the Study:
- To investigate the neuronal basis of functional magnetic resonance imaging (fMRI) responses in the primary somatosensory cortex (SI) after peripheral nerve injury.
- To differentiate the activity of interneurons and principal neurons in the SI cortex following nerve damage.
Main Methods:
- High-resolution functional magnetic resonance imaging (fMRI) in rats.
- In vivo electrophysiological recordings, including local field potentials (LFPs) and single-unit activity.
- Juxtacellular neuronal labeling and immunostaining to identify neuron types.
Main Results:
- Significant bilateral increases in fMRI responses were observed in the SI cortex of rats with peripheral nerve injury.
- In the healthy SI, increased fMRI responses correlated with increased LFP amplitude and single-unit activity.
- In the deprived SI, increased fMRI responses were associated with minimal LFP changes but increased single-unit activity, identified as interneurons.
Conclusions:
- Increased fMRI responses in the deprived SI cortex following peripheral nerve injury are primarily driven by enhanced interneuron activity.
- This suggests a specific neuronal mechanism underlying cortical reorganization after nerve damage.
