Effect of transcutaneous electrical nerve stimulation (TENS) on central nervous system amplification of somatosensory input

Abstract

The effect of transcutaneous electrical nerve stimulation (TENS) on the central nervous system amplification process was investigated focusing on the dorsal column-medial lemniscal pathway, because the dorsal column nucleus was recently shown to receive multiple sources of sensory information, including pain. Short latency somatosensory evoked potentials (SSEPs) were recorded in ten healthy normal volunteers. Amplitude changes in each SSEP component (the N9 brachial plexus potential, the P14 potential that originates from the cervicomedullary junction, spinal N13/P13 generated by the cervical dorsal horn and the cortical N20/P25 potential) were studied at stimulus strengths ranging from the threshold (40% maximum stimulus) to 2.5 times the threshold (maximum). The findings suggest that sensory amplification begins at the P14 generator source near the cuneate nucleus. There was no statistically significant difference in sensory amplification between P14 and cortical N20/P25, indicating that the cuneate nucleus is the main site of the central amplifying process. When TENS was applied to the palm distal to the median nerve stimulation used for SSEP, cortical N20/P25 amplification disappeared, evidence that TENS suppresses the central amplification phenomenon, most probably at the level of the cuneate nucleus.

Neural Acupuncture Unit: A New Concept for Interpreting Effects and Mechanisms of Acupuncture

“…These data suggest the involvement of the dorsal column-medial lemniscus tract in the modulation of acupuncture effects, particularly in regulating visceral functions [91]. This is consistent with the central actions of transcutaneous electrical nerve stimulation (TENS), of which the activation of the dorsal column pathway is believed to be the principal mechanism [92]. …”

AMPA and GABAA/B receptor subunit expression in the cuneate nucleus of adult squirrel monkeys during peripheral nerve regeneration

“…This has substantial influence on receptive field expression at lower levels of the ascending neuroaxis [1,2, 3,5, 34, 35, 38, 39, 40, 54, 56 57, 58]. While corticofugal feedback does play an important role in both immediate unmasking and reorganization within subcortical structures [6, 13, 17, 27, 31, 58], the time-course and extent of changes occurring in the brainstem impose important limitations on cortical reorganization.…”

Modulation of human corticospinal excitability by paired associative stimulation

“…Lakhani et al, 2012; Gatica Tossi et al, 2013), an effect that remains evident at 2.5 times MT (Urasaki et al, 1998). While components of the S1 SEP appear to saturate at some point below the pain threshold (PT) (Parain and Delapierre, 1991), MEG recordings suggest that the asymptote of the S2 response occurs at lower stimulation intensities than for the S1 response (Lin et al, 2003).…”