Our study highlights the antinociceptive effect of this technique and may contribute to the understanding of the mechanisms underlying pain relief. The pharmacologic prolongation of the excitability-diminishing after-effects would render the method applicable to different patient populations with chronic pain.

Theta burst stimulation (TBS) is a special repetitive transcranial magnetic stimulation (rTMS) paradigm, where bursts of low-intensity stimuli are applied in the theta frequency. The aim of this study was to investigate the eVect of neuronavigated TBS over primary somatosensory cortex (SI) on laser-evoked potentials (LEPs) and acute pain perception induced with Tm : YAG laser stimulation. The amplitude changes of the N1, N2, and P2 components of LEPs and related subjective pain rating scores of 12 healthy subjects were analyzed prior to and following continuous TBS (cTBS), intermittent TBS (iTBS), intermediate TBS (imTBS), and sham stimulation. Our results demonstrate that all active TBS paradigms signiWcantly diminished the amplitude of the N2 component, when the hand contralateral to the site of TBS was laser-stimulated. Sham stimulation condition had no signiWcant eVect. The subjective pain perception also decreased during the experimental sessions, but did not diVer signiWcantly from the sham stimulation condition. The main Wnding of our study is that TBS over SI diminished the amplitude of the N2 component evoked from the contralateral side without any signiWcant analgesic eVects. Furthermore, imTBS produced responses similar to those observed by other forms of TBS induced excitability changes in the SI.