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Tactile Semiautomatic Passive-Finger Angle Stimulator (TSPAS)
Published on: July 30, 2020
Tactile co-activation improves detection of afferent spatial modulation
Gregory O Gibson1, Christopher D Makinson, Krish Sathian
1Rehabilitation R&D Center of Excellence, Atlanta VAMC, Atlanta, USA.
Experimental Brain Research
|February 10, 2009
Summary
Tactile co-activation did not improve spatial acuity using grating orientation or 3-dot tasks. However, it enhanced performance on the smooth-grooved surface discrimination task, suggesting its suitability for measuring tactile sensitivity changes.
Area of Science:
- Neuroscience
- Somatosensory research
- Tactile perception
Background:
- Tactile co-activation, or synchronous skin stimulation, is thought to enhance tactile spatial acuity.
- Previous studies suggest it expands cortical representation, but the precise nature of these changes requires clarification.
Purpose of the Study:
- To investigate the effects of tactile co-activation on tactile sensitivity using controlled mechanical stimulation.
- To determine which tactile sensitivity measures are most appropriate for detecting changes induced by co-activation.
Main Methods:
- Three tactile sensitivity tasks were employed: grating orientation (GR/OR) discrimination, 3-dot acuity task, and smooth-grooved (SM/GV) surface discrimination.
- Experiment 1 used GR/OR and 3-dot tasks. Experiment 2 used GR/OR and SM/GV tasks, including a control group.
Main Results:
- Tactile co-activation did not significantly improve performance on the GR/OR or 3-dot tasks in Experiment 1.
- In Experiment 2, GR/OR performance showed no significant improvement in either group, but SM/GV performance significantly improved in the experimental group compared to the control group.
Conclusions:
- The grating orientation and 3-dot tasks are not sensitive to changes induced by tactile co-activation.
- The smooth-grooved surface discrimination task is a more suitable measure for detecting tactile sensitivity enhancements following co-activation.
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