Fig. 8

The slow bursting pattern versus continuous activation. The CM-fiber on the left has a stable latency of 144 ms whereas the CMi-fiber on the right has a slower stable latency of 288 ms. The C-fibers were recorded at two different sites. The gray bar shows the time from injection (first dashed line) to the time of removal of the needle (second dashed line). We injected β-alanine for the CM-fiber and introduced a histamine skin prick into the receptive field of the CMi-fiber. During this time, mechanical activation cannot be distinguished from chemical activation. The “slow bursting pattern” can be observed in the CM-fiber response to β-alanine, differing from the irregular response of the CMi-fiber to histamine