pyramidal tract


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pyramidal tract

n.
A major pathway of the central nervous system, originating in the sensorimotor areas of the cerebral cortex and generally descending through the brainstem to the spinal cord. The fibers of the pyramidal tract transmit motor impulses that control voluntary movement.

pyram′idal tract`


n.
any of the bundles of motor fibers extending from the cerebral hemispheres into the medulla and spinal cord.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pyramidal tract - any of the important motor nerves on each side of the central nervous system that run from the sensorimotor areas of the cortex through the brainstem to motor neurons of the cranial nerve nuclei and the ventral root of the spinal cordpyramidal tract - any of the important motor nerves on each side of the central nervous system that run from the sensorimotor areas of the cortex through the brainstem to motor neurons of the cranial nerve nuclei and the ventral root of the spinal cord
efferent, efferent nerve, motor nerve - a nerve that conveys impulses toward or to muscles or glands
central nervous system, CNS, systema nervosum centrale - the portion of the vertebrate nervous system consisting of the brain and spinal cord
basal ganglion - any of several masses of subcortical grey matter at the base of each cerebral hemisphere that seem to be involved in the regulation of voluntary movement
References in periodicals archive ?
Diffusion tensor imaging detects early Wallerian degeneration of the pyramidal tract after ischemic stroke.
It is proposed that cortical myoclonus arises from abnormal excitation of corticospinal output, as suggested by following: (1) cortical myoclonus shows a time-locked premyoclonus EEG discharge reflecting apical dendrite excitation of pyramidal neurons; (2) myoclonus event latency is consistent with pyramidal tract conduction.
It may be essentially benign or secondary due to a lesion in basal ganglia, pyramidal tract, and trauma, local pathology in the eyes or drug induced.
His MRI spine showed thin strip of white matter with hyperintensities confined to anterior part of spinal cord consistent with involvement of pyramidal tract.
Pyramidal tract involvement is infrequent, however, our patient had involvement of pyramidal tracts manifested by hyperreflexia and ankle clonus.
The most important obstacles against eliciting quantitative information about the lesions involving the descending motor pathways are the variabilities in the latency amplitude, and shape of the motor responses elicited by motor cortex stimulation (predominantly caused by the variable activation level of the target muscle) and the uncertainty about whether, via magnetic stimulation, the whole population of the pyramidal tract fibers can be activated.
Therefore, the reason for the severe paralysis of the patient's left upper and lower limbs is damage caused by the lesion of one of the descending fibers; in other words, the pyramidal tract (corticospinal tract).
The big toe going up suggests a possible disturbance of the pyramidal tract (van Gijn 1995).
There was no evidence of sensory or pyramidal tract involvement.