Yoshiyuki Hirano1, Junjie Liu2,
Afonso C. Silva2
1Cerebral Microcirculation
Unit, Laboratory of Functional & Molecular Imaging, National Institute of
Neurological Disorders & Stroke, National Institutes of Health, Bethesda,
MD, United States; 2Cerebral Microcirculation Unit, Laboratory of
Functional & Molecular Imaging,, National Institute of Neurological
Disorders & Stroke, National Institutes of Health,, Bethesda, MD, United
States
The use of fMRI to understand the cortical representation of tactile information of the hands is of current interest. Here, we used BOLD fMRI to measure the hemodynamic response to unilateral and bilateral somatosensory stimulation paradigms in awake marmosets. Robust responses were obtained in contralateral SI to 4 and 40 Hz unilateral stimulation. However, the ipsilateral cortex yielded negative and positive responses, respectively. Moreover, bilateral stimuli produced positive responses of higher amplitudes than the summation of the responses to unilateral stimuli. These findings suggest that bilateral stimulation always facilitates the hemodynamic response in S1 through transcallosal interactions.