Yilei Zhao MD, Presenter: Nothing to Disclose

Xuning Zhen, Abstract Co-Author: Nothing to Disclose

Minming Zhang MD, PhD, Abstract Co-Author: Nothing to Disclose

Movement dysfunction in Parkinson's disease (PD) is well documented. Current observations suggest these impairments may be attributed to dysfunction of integrating process in sensory and movement. Here, sensory and movement integration functional magnetic resonance imaging (fMRI) protocol was used in early stage PD patients and matched controls to investigate the underlying neural mechanisms of these problems.

Twenty-one right-handed patients with early PD were recruited. They were assessed with the UPDRS, the Hoehn and Yahr disability Scale and MMSE . Controls included twenty-two age-matched normal subjects. The experimental design was block design,there were three types tasks (tactile, movement and integrate task).Image collecting included EPI gradient echo sequence to obtain functional images and high solution 3D TIWI anatomy images. Imaging data analysis was conducted with SPM2 software (Wellcome Institute of Cognitive Neurology, London, UK). The contrast estimates were entered into a standard SPM second-level analysis with subject treated as a random effect. All coordinates reported were in Talarirach space convered from MNI space.

1. The controls showed an extensive network of cortical and subcortical regions involving in sensation- motor integration, including areas of somatosensory cortex and the inferior parietal lobule, middle frontal gyrus, premotor cortex, middle temporal gyrus (MT/V5) and cerebellar hemispheres. 2. The decreased activation was observed in the early stage PD group in the somatosensory and motor brain regions when performing passive tactile and movement tasks. 3. In controls, the extrastriate visual cortex activated greater than PD patients during three tasks performance. 4. Greater activation was found in the PD group in bilateral prefrontal regions when performing task of sensation-movement integration.  

The extrastriate visual cortex maybe are multisensory regions and play an important role in sensorimotor integration, nevertheless, in early stage PD, nigrostriatal dopamine depletion and intracortical dopamine deficiency may leads to the decreased activation in extrastriate visual cortex, to fulfill these integrate processing, the compensation in bilateral prefrontal lobe will be happen.

fMRI can demostrate the different integration areas of cerebral cortex from sensation to movement in normal and early PD patients.

Zhao, Y, Zhen, X, Zhang, M, Sensorimotor Integration Impairments in Early Parkinsons Disease Are Accompanied by Reductions in Activity in Extrastriatal Visual Cortex.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11012806.html