Acoustic tone or medial geniculate stimulation cue training in the rat is associated with neocortical neuroplasticity and reduced akinesia under haloperidol challenge

Abstract

Sensory cues can improve movement deficits in Parkinson's disease, but little is known about the mechanisms involved. To investigate neuroplastic changes following sensorimotor cue training, rats were shaped to respond to acoustic tone or medial geniculate stimulation cues by retrieving a food reward. Neuroplasticity associated with training was assessed by changes in auditory neocortical evoked field potentials and dendritic morphology. Stimulation cue training was associated with changes in dendritic arbour length and complexity in auditory and motor neocortices, but was without effect on evoked electrophysiological responses. Tone cue training was associated with a significant increase in peak height of the evoked auditory response and then under haloperidol challenge, demonstrated reduced akinesia. Results indicate that cue-training induces neuroplastic changes that may be related to improved sensorimotor function under dopaminergic antagonism.