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Stimulation Location Determination using a 3D Digitizer with High-Definition Transcranial Direct Current Stimulation
Published on: December 20, 2019
Dodecapus: An MR-compatible system for somatosensory stimulation.
Ruey-Song Huang1, Martin I Sereno
1Department of Cognitive Science 0515, University of California San Diego, La Jolla, CA 92093-0515, USA.
Neuroimage
|December 22, 2006
Summary
A novel Dodecapus system enables precise tactile stimulation for functional magnetic resonance imaging (fMRI) somatotopic mapping. This system successfully mapped representations of the face, lips, and fingers in multiple brain regions.
Area of Science:
- Neuroscience
- Neuroimaging
- Human Somatosensory System
Background:
- Somatotopic mapping of the human body surface using fMRI presents challenges, including difficulties in delivering tactile stimuli within the scanner and the need for multiple stimulators for complex body areas.
- Accurate localization of cortical representations requires precise and systematic tactile stimulation.
Purpose of the Study:
- To develop and validate a computer-controlled pneumatic system for automated, precise tactile stimulation during fMRI.
- To map the somatotopic representations of the face, lips, and fingers in the human brain using the developed system.
Main Methods:
- Construction of a computer-controlled pneumatic system delivering air puffs to 12 body surface locations via an MR-compatible manifold (Dodecapus).
- Utilized block-design 'Localizer' and 'Phase-encoded' fMRI paradigms to identify and map cortical representations.
- Stimulation was systematically delivered to the face, lips, and fingers during functional scans.
Main Results:
- Successfully localized and mapped multiple somatotopic representations for the face, lips, and fingers.
- Identified these representations across various cortical areas, including primary motor cortex (MI), premotor cortex (PMv), somatosensory cortex (SI, SII), and parietal areas (PV, 7b, AIP, VIP).
- The Dodecapus system demonstrated portability, ease of setup, and no radiofrequency interference.
Conclusions:
- The Dodecapus system provides a portable, versatile, and effective solution for non-invasive somatotopic mapping using fMRI.
- This technology facilitates precise tactile stimulation, enabling detailed mapping of body surface representations in the brain.
- The system's applicability extends to EEG and MEG, offering broad utility in basic and clinical neuroscience research.
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