Pain threshold and polysynaptic components of the blink reflex in Parkinson's disease.

This study was conducted on 15 outpatients with idiopathic Parkinson's disease, 10 on chronic levodopa therapy and 5 drug free, all complaining of painful syndromes. We investigated the perceptive and pain thresholds and the threshold of polysynaptic components of the blink reflex in patients and 8 controls. Our data indicate that as regards the perceptive, pain and R2, R3 thresholds, patients with and without levodopa therapy do not differ significantly from controls.