A measure of striatal function predicts motor stereotypy

To identify basal ganglia circuit dysfunctions that might produce repetitiv e behaviors known as motor stereotypies, we applied psychomotor stimulants and a direct dopamine receptor agonist to induce different levels of stereo typy in rats. We then used a gene induction assay to measure the functional activation of neurons in the neurochemically distinct compartments of the striatum, the striosomes and the extrastriosomal matrix. The amount by whic h activation in the striosomes exceeded activation in the matrix predicted the degree of motor stereotypy induced by the drug treatments. These result s suggest that imbalance between compartmentally organized basal ganglia ci rcuits may represent a neural correlate of motor stereotypy.