[Activity and function of neurons in the globus pallidus in Parkinson's disease]

We investigated the activity and functional distribution of globus pallidus neurons in Parkinson's disease patients and recorded single cell activity of globus pallidus medialis and changes related to the movements of different joints in 31 patients during stereotactic ventral pallidotomy procedure. We showed that discharge rates of 19% of medial globus pallidus neurons were modulated by passive contralateral movements; 77.2% of these pallidal units showed changes related solely to single joint movement and 22.8% showed different patterns of activity in relation to two and more joints. We also identified somatotopically arranged cell clusters that alter the discharge rate with related movements; oro-facial movement-related cells in caudo-ventral region and, leg-related cells in dorso-rostral part and arm-related cells between these two parts of medial globus pallidus. These findings suggest a partial somatotopic organization of human globus pallidus medialis.