Model
Digital Document
Publisher
Florida Atlantic University
Description
Rats with lesions of the ventromedial aspect of the internal
capsule in the vicinty of the entopeduncular nucleus (EP) showed a loss
of forelimb placing (chin, contact and visual) in the contralateral
limb. Spreading depression induced by instillation of KCl (25%) to the
cortex contralateral to the lesion brought back placing in the affected
limb and abolished placing in the normal limb. Within 24 hours the
pre-spreading depression state returned and the impaired limb no longer
placed while the normal limb recovered function. In contrast, KCl on
the ipsilateral cortex did not reinstate placing. These results
suggest that the loss of placing following lesions of the EP are due to
tonic inhibition from the cortex contralateral to the lesion. Sensory
summation was evident during the early recovery period when placing was
accomplished only if two kinds of stimuli were provided
simultaneously. Forelimb placing recovered to its pre-lesion state.
capsule in the vicinty of the entopeduncular nucleus (EP) showed a loss
of forelimb placing (chin, contact and visual) in the contralateral
limb. Spreading depression induced by instillation of KCl (25%) to the
cortex contralateral to the lesion brought back placing in the affected
limb and abolished placing in the normal limb. Within 24 hours the
pre-spreading depression state returned and the impaired limb no longer
placed while the normal limb recovered function. In contrast, KCl on
the ipsilateral cortex did not reinstate placing. These results
suggest that the loss of placing following lesions of the EP are due to
tonic inhibition from the cortex contralateral to the lesion. Sensory
summation was evident during the early recovery period when placing was
accomplished only if two kinds of stimuli were provided
simultaneously. Forelimb placing recovered to its pre-lesion state.
Member of