After damage to afferents from the hand as they course in the dorsal columns of the spinal cord, deprived portions of the brainstem cuneate nucleus, somatosensory thalamus, and somatosensory cortex become unresponsive to tactile stimuli and hand use is impaired. However, within 1 - 2 months, cortex can be reactivated by a few surviving dorsal column afferents, and hand use improves. We will evaluate the relationships between (1) the recovery of hand use, (2) the time course of the reactivation of cortex, (3) the recovery of response properties of cortical neurons, (4) the sprouting and growth of surviving dorsal column afferents in the cuneate nucleus of the lower brainstem to contact more neurons, and (5) the cellular and histochemical consequences in the cuneate nucleus of partial deafferentation. In addition, we will evaluate the effectiveness of two treatments, (6) chondroitinase ABC and (7) anti-Nogo-A, on sprouting new growth of surviving dorsal column afferents in the cuneate nucleus. The research is designed to provide an understanding of the major mechanisms of recovery of somatosensory system function after a sensory loss in humans, and to help develop favorable therapeutic approaches for humans with sensory loss after spinal cord injury.

Public Health Relevance

The proposed research seeks to evaluate the hypothesis that a few preserved sensory afferents in the dorsal columns of the spinal cord injury can mediate the recovery of hand use by sprouting to activate a large population of neurons in the brainstem and thereby, the cortex. The proposed research will also evaluate two treatments that are likely to promote the growth of the preserved sensory afferents.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS016446-32
Application #
8294547
Study Section
Somatosensory and Chemosensory Systems Study Section (SCS)
Program Officer
Gnadt, James W
Project Start
1980-07-01
Project End
2014-07-31
Budget Start
2012-08-01
Budget End
2013-07-31
Support Year
32
Fiscal Year
2012
Total Cost
$427,557
Indirect Cost
$153,482
Name
Vanderbilt University Medical Center
Department
Psychology
Type
Schools of Arts and Sciences
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
Stepniewska, Iwona; Gharbawie, Omar A; Burish, Mark J et al. (2014) Effects of muscimol inactivations of functional domains in motor, premotor, and posterior parietal cortex on complex movements evoked by electrical stimulation. J Neurophysiol 111:1100-19
Molnár, Zoltán; Kaas, Jon H; de Carlos, Juan A et al. (2014) Evolution and development of the mammalian cerebral cortex. Brain Behav Evol 83:126-39
Qi, Hui-Xin; Reed, Jamie L; Gharbawie, Omar A et al. (2014) Cortical neuron response properties are related to lesion extent and behavioral recovery after sensory loss from spinal cord injury in monkeys. J Neurosci 34:4345-63
Yang, Pai-Feng; Qi, Hui-Xin; Kaas, Jon H et al. (2014) Parallel functional reorganizations of somatosensory areas 3b and 1, and S2 following spinal cord injury in squirrel monkeys. J Neurosci 34:9351-63
Cerkevich, Christina M; Qi, Hui-Xin; Kaas, Jon H (2014) Corticocortical projections to representations of the teeth, tongue, and face in somatosensory area 3b of macaques. J Comp Neurol 522:546-72
Qi, Hui-Xin; Gharbawie, Omar A; Wynne, Katherine W et al. (2013) Impairment and recovery of hand use after unilateral section of the dorsal columns of the spinal cord in squirrel monkeys. Behav Brain Res 252:363-76
Kaas, Jon H (2013) The Evolution of Brains from Early Mammals to Humans. Wiley Interdiscip Rev Cogn Sci 4:33-45
Young, Nicole A; Collins, Christine E; Kaas, Jon H (2013) Cell and neuron densities in the primary motor cortex of primates. Front Neural Circuits 7:30
Collins, C E; Leitch, D B; Wong, P et al. (2013) Faster scaling of visual neurons in cortical areas relative to subcortical structures in non-human primate brains. Brain Struct Funct 218:805-16
Liao, Chia-Chi; Gharbawie, Omar A; Qi, Huixin et al. (2013) Cortical connections to single digit representations in area 3b of somatosensory cortex in squirrel monkeys and prosimian galagos. J Comp Neurol 521:3768-90

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