Figure 7.

Schematic diagram of activation of afferent fibers with sine-wave stimuli. The pie showed the number of three types of rat DRG neurons as reported by Djouhri et al [32]. The height represented normalized AP frequencies produced by sine-wave stimuli in the three types of fibers in our study relative to those by natural stimuli reported previously [31]. This figure shows the selectivity of the sine-wave stimuli to activate afferent fibers as described in 'Discussion'.