Change to Current Perception and Pain Tolerance Thresholdsfollowing Repetitive Transcranial Magnetic Stimulation

Sohn, Min Kyun; Cho, Kang Hee; Jee, Sung Ju; Lee, Tae Sung

Abstract

OBJECTIVE
To investigate the effect of high-frequency repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex on sensory and pain perception. METHOD: We measured the current perception threshold and the pain tolerance threshold with Neurometer? CPT/C in 14 healthy subjects (eleven males and three females, mean age: 25.0 years). Threshold testing was evaluated prior to, immediately after, 30 min after and 60 min after rTMS. The stimulation parameters were a frequency of 10 Hz and a field intensity of 100% of the active motor thresholds. Stimuli were provided in trains of 100 pulses, followed by a 50s rest period, 10 trains were applied in the session, resulting in 1,000 pulses in total.
RESULTS
The current perception thresholds of 5, 250, 2,000 Hz were significantly increased immediately, 30 min after rTMS (p<0.05) and no effects at all were noticed after sham rTMS. The pain tolerance thresholds of 5, 250 Hz were significantly increased immediately, 30 min after rTMS and the pain tolerance threshold of 2,000 Hz were significantly increased immediately, 30 min, 60 min after rTMS (p< 0.05). No effects at all were noticed after sham rTMS.
CONCLUSION
After high frequency rTMS over the primary motor cortex, we found that the current perception thresholds and the pain tolerance thresholds of 5, 250, 2,000 Hz were significantly increased.