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Published on: June 14, 2014
Continuous theta-burst rTMS over primary somatosensory cortex modulates tactile perception on the hand
N Rai1, A Premji, M Tommerdahl
1Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada.
Summary
Continuous theta-burst stimulation (cTBS) over the primary somatosensory cortex (SI) impairs tactile spatial and temporal acuity. This effect lasted for up to 18 minutes, suggesting cTBS may reduce sensory processing.
Area of Science:
- Neuroscience
- Somatosensory system research
- Brain stimulation techniques
Background:
- Theta-burst stimulation (TBS) modulates cortical excitability.
- Intermittent TBS (iTBS) of the primary somatosensory cortex (SI) enhances tactile spatial acuity.
- The impact of continuous TBS (cTBS) on tactile acuity is not well understood.
Purpose of the Study:
- To investigate the effects of cTBS over SI on tactile spatial and temporal acuity.
- To determine the duration of these effects on sensory perception.
Main Methods:
- Participants underwent real or sham cTBS over the left SI.
- Temporal discrimination threshold (TDT) and spatial amplitude discrimination threshold (SDT) were measured from the right hand.
- Measurements were taken before and up to 34 minutes after stimulation.
Main Results:
- Real cTBS significantly reduced both temporal and spatial tactile acuity.
- These impairments in tactile acuity persisted for up to 18 minutes post-stimulation.
- Sham cTBS did not alter tactile acuity.
Conclusions:
- Continuous TBS applied to the SI temporarily impairs both temporal and spatial tactile sensory processing.
- This suggests cTBS may decrease neural activity in the targeted cortical region.
- Potential therapeutic applications may involve reducing excessive sensory input.
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