Related Experiment Video
Updated: Aug 11, 2026

Unilateral Pyramidotomy of the Corticospinal Tract in Rats for Assessment of Neuroplasticity-inducing Therapies
Published on: December 15, 2014
Redundancy in ascending and descending pathways mediating head turning elicited by entopenducular stimulation in the
Abstract:
Contraversive turning movements of the head were elicited in alert cats by unilateral electrical stimulation of the entopeduncular nucleus. To determine the relative functional importance of ascending and descending pathways activated by the stimulation, the animals were submitted to thalamocortical or midbrain lesions and to combinations of the two lesions interrupting the pathways. Head turning was hindered considerably only after combinations of the two lesions and not after either lesion alone. Taking into account the results of previous studies, showing that most efferent fibers of the entopeduncular nucleus branch to the thalamus and to the midbrain, it is concluded that not only one but two main efferent pathways, corresponding to each branch, are used by the entopeduncular nucleus to control motoneurons, each pathway carrying enough redundant information to mediate head turning.
Related Concept Videos
Diencephalon: Thalamus and Information Relay
Major Somatic Sensory Pathways
Direct Motor Pathways
The corticospinal tract is responsible for the voluntary movement of the limbs and trunk. It originates in the cerebral cortex of the brain and descends through the cerebrum's internal capsule and the...
Indirect Motor Pathways
The vestibulospinal tract originates in the vestibular nuclei of the brainstem. The vestibular system detects changes in...
Auditory Pathway
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
Equilibrium and Balance

