Fig. 5

Heat response of cutaneous afferents. a Response patterns of heat-sensitive C-fiber afferents to a ramped heat stimulus (from 32 to 50 °C in 30 s). Each data point is represented by the mean discharge rate ± its SEM (gray lines). Two-way repeated measures ANOVA with Geisser–Greenhouse correction revealed a significant effect of TIME (F_{(2.993, 149.7)} = 16.21, p < 0.0001, partial η² = 0.387), but insignificant effects of GROUP (F_{(1, 50)} = 0.304, p = 0.584, partial η² = 0.012) and GROUP x TIME interaction (F_{(30, 1500)} = 0.665, p = 0.916, partial η² = 0.027). b. Threshold temperature to heat stimulation. c Response magnitude (net evoked spikes). No significant differences were observed in the response threshold and magnitude between the CTR (n = 26) and IM (n = 26) groups (Mann–Whitney U test for b and c)