Comparison of cortical activation patterns by somatosensory stimulation on the palm and dorsum of the hand. (1st September 2013)

• Record Type: Journal Article
• Authors: Jang, Sung Ho; Seo, Jeong Pyo; Ahn, Sang Ho; Lee, Mi Young
• Is Part Of: Somatosensory & motor research. Volume 30:Number 3(2013)
• Page Start: 109
• Page End: 113
• Publication Date: 2013-09-01
• Subjects: Cortical activation -- functional magnetic resonance imaging -- somatosensory stimulation -- touch; Skin -- Innervation -- Periodicals; Somesthesia -- Periodicals; Perceptual-motor processes -- Periodicals; 573.85
• DOI: 10.3109/08990220.2013.775117
• Languages: English
• ISSNs: 0899-0220

Abstract

Abstract: Objectives : Little is known about differences of cortical activation according to body location. We attempted to compare brain activation patterns by somatosensory stimulation on the palm and dorsum of the hand, using functional magnetic resonance imaging (fMRI). Method : We recruited 15 healthy right-handed volunteers for this study. fMRI was performed during touch stimulation using a rubber brush on an area of the same size on the palm or dorsum of the hand. Regions of interest (ROIs) were drawn at the primary sensory–motor cortex (SM1), posterior parietal cortex, and secondary somatosensory cortex. Results : Group analysis of fMRI data indicated that touch stimulation on the palm resulted in production of more activated voxels in the contralateral SM1 and posterior parietal cortex than on the dorsum of the hand. The most activated ROI was found to be the contralateral SM1 by stimulation of the palm or dorsum, and the number of activated voxels (5875) of SM1 by palm stimulation was more than 2 times that (2282) of dorsum stimulation. The peak activated value in the SM1 by palm stimulation (16.43) was also higher than that of the dorsum (5.52). Conclusion : We found that stimulation of the palm resulted in more cortical activation in the contralateral SM1 than stimulation of the dorsum. Our results suggested that the palm of the hand might have larger somatotopy of somatosensory representation for touch in the cerebral cortex than the dorsum of the hand. Our results would be useful as a rehabilitation strategy when more or less somatosensory stimulation of the hand is necessary.