Several studies suggest that acute pain decreases corticomotor excitability. However, the variability between individuals remains important and unexplained. The aim of this study was to unveil potential sources of variation by looking at the effect of kinesiophobia and pain catastrophizing on pain-induced corticomotor modulation.

Corticomotor excitability was assessed with the slopes of recruitment curves measured from the first dorsal interosseous elicited by transcranial magnetic stimulation before and during pain induced by capsaicin application on the forearm. Participants completed the Tampa Scale for Kinesiophobia (TSK) and the Pain Catastrophizing Scale (PCS).

Twenty-four persons participated in the study. There was a moderate and positive correlation between individual changes in the slope of the recruitment curves and TSK questionnaire scores (r_s=0.47; p = 0.02). During the painful condition, unlike those with higher TSK scores, participants with lower TSK scores demonstrated recruitment curves with reduced slopes compared to baseline. There was a difference between changes in the slopes of recruitment curves between individuals with “highest” vs. “lowest” kinesiophobia scores (p = 0.01). No relationship was observed between changes in the slopes of the recruitment curves and PCS scores (p = 0.20).

The results suggest that kinesiophobia may affect neuromotor processes and influence the corticomotor pain response.

Higher kinesiophobia scores during experimental induced pain were associated with smaller decreases in the slopes of recruitment curves. These findings suggest that there is less inhibition of corticospinal excitability in participants with greater TKS scores.