Quantitative registration of motor disorders following bilateral lesions of substantia nigra in the rat.

Abstract

Bilateral lesions in the substantia nigra were induced in rats trained in an instrumental learning program comparable with a fixed-interval schedule. General observations and examinations of rough motor behavior revealed rigidity, a decrease in spontaneous activity and a loss of postural reflexes. The analysis of lever-pressing rates results in a differentiation of rigidity and akinesia which is in accordance with the overt motor disturbances, dependent on the size of the nigral lesions.