Dolore e coscienza, uno studio TMS/EEG

[Autom. eng. transl.] The present research aims to investigate the mechanisms of pain perception through transcranial magnetic stimulation (rTMS) to study the effect on acute pain experience. On a sample of healthy subjects, to induce an acute and experimentally controlled pain sensation, a capsaicin-based gel was used, applied to the back of the non-dominant hand after stimulation with TMS (10-minutes 5Hz applied to the left dorsolateral prefrontal cortex, DLPFC). The experimental design included five five-minute recording blocks through electroencephalography (EEG), at the end of which Visual-Analogue Scale (VAS) was administered to measure the intensity of the pain sensation. The five blocks consisted of a pre-stimulation baseline with TMS and four consecutive blocks after stimulation. The results show greater cortical activation in the frontal area involving the Theta band after stimulation with rTMS. These data are supported by behavioral measures, in particular from the scores on the VAS scales, which show an increase in the values related to the intensity of the pain experienced and a dilated perception of the passage of time for the subjects who received the stimulation. It is hypothesized that these results represent a significant modulation effect on the monitoring and control experiences related to the experience of pain, after the application of a rTMS on the left DLPFC. The use of a TMS paradigm suggests a relevant role of DLPFC in the monitoring and inhibition processes within the painful experience, probably related to an increase in pain awareness. However, the results may suggest clinical interventions to relieve pain in chronic patients where non-invasive techniques can supplement drug treatment.