639.11/M15

Widespread decreases in cerebral cortical activation during tactile perception in Parkinson’s disease

Georgia World Congress Center: Halls B3-B5

Tuesday, Oct 17, 2006, 3:00 PM - 4:00 PM

*K. SATHIAN¹, E. L. MARIOLA¹, R. F. STILLA¹, M. ZHANG²;
¹Dept Neurology, Emory Univ Sch Med, Atlanta, GA, ²Dept Radiology, First Affiliated Hospital, Zhejiang Univ Med School, Hangzhou, CHINA.

Previous work from our laboratory (Sathian et al., Neurology 49: 168-177, 1997) has demonstrated abnormalities of tactile discrimination of grating orientation and texture in patients with Parkinson’s disease (PD). In the present study, we used functional magnetic resonance imaging (fMRI) to investigate neural activity during tactile perception in patients with PD and age-matched normal controls. Gratings were applied manually to the pad of the immobilized right thumb, oriented either along or across its long axis. Subjects made keypress responses with the fingers of the left hand to indicate grating orientation. A block design was used, with blocks of the grating orientation task alternating with baseline blocks without stimulation but requiring keypress responses. Blood oxygenation level dependent (BOLD) functional imaging was performed on a 3T Siemens Trio scanner. Image analysis was carried out using BrainVoyager QX. A random effects analysis identified an extensive neural network of regions where activity was higher in controls than in PD patients. This network included multiple foci within visual cortex. These neuroimaging findings suggest that impaired tactile performance in PD patients is associated with widespread dysfunction of cerebral cortex outside the traditional “motor circuit”.

 K. Sathian , None; E.L. Mariola, None; R.F. Stilla, None; M. Zhang, None.

NINDS