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Published on: May 23, 2011
Differences in perception and brain activation following stimulation by large versus small area cutaneous surface
D Lelic1, C D Mørch, K Hennings
1Mech-Sense, Department of Gastroenterology, Aalborg Hospital, Aarhus University, Aalborg, Denmark. dl@mech-sense.com
European Journal of Pain (London, England)
|February 17, 2012
Summary
Cutaneous pin electrode (CPE) stimulation preferentially activates nociceptive brain areas compared to conventional surface electrodes. This suggests CPE is a superior tool for studying pain perception and nociception.
Area of Science:
- Neuroscience
- Pain Research
- Electrophysiology
Background:
- Conventional electrical stimulation activates both pain and non-pain nerve fibers.
- Small area pin electrodes were developed to selectively activate nociceptors.
- Previous subjective reports suggested pin electrodes preferentially activate nociceptors.
Purpose of the Study:
- To demonstrate that cutaneous pin electrode (CPE) stimulation activates brain areas involved in nociceptive processing more than conventional surface electrodes.
- To compare brain activation patterns between CPE and conventional surface electrode stimulation.
Main Methods:
- Evoked potentials (EPs) were recorded from 62 scalp electrodes in 12 healthy volunteers.
- Electrical stimulation was delivered using both conventional surface and CPE electrodes at 10 times sensory threshold.
- Brain electrical source analysis was used to build dipolar models of brain activity.
Main Results:
- Conventional electrodes activated the primary somatosensory cortex, secondary somatosensory cortex (SII), and mid-cingulate cortex.
- CPE stimulation activated bilateral SII, bilateral insula, and mid-cingulate cortex, similar to laser-evoked potentials.
- The similarity to laser-evoked potentials suggests CPE primarily engages nociceptive pathways.
Conclusions:
- CPE significantly activates nociceptive brain areas more than conventional surface electrodes.
- CPE is recommended for future research investigating nociception using electrical stimuli.
- This finding supports the use of CPE for targeted studies of pain perception.
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