Sensory processing in Parkinson's and Huntington's disease

Abstract

Investigated the functional anatomy of sensory processing in 2 clinical conditions characterized by basal ganglia dysfunction, Parkinson's disease (PD) and Huntington's disease (HD). Eight 52-70 yr old PD patients, 8 33-63 yr old HD patients and 8 healthy controls underwent repetitive H2150-positron emission tomography activation scans during continuous unilateral high-frequency vibratory stimulation of the immobilized metacarpal joint of the index finger, and rest. Comparisons of vibration-induced rCBF changes between PD and HD patients and controls revealed differences in central sensory processing. In both conditions there was relative enhanced activation of ipsilateral sensory cortical areas. These results show that PD and HD, beyond well-established deficits in central motor control, are characterized by abnormal cortical and subcortical activation on passive sensory stimulation. The finding that activation increases in ipsilateral sensory cortical areas may indicate either altered central focusing and gating of sensory impulses, or enhanced compensatory recruitment of associative sensory areas in the presence of basal ganglia dysfunction. Altered sensory processing is thought to contribute to motor deficits in both conditions. (PsycINFO Database Record (c) 2016 APA, all rights reserved)