Analysis of the selective nature of sensory nerve stimulation using different sinusoidal frequencies

This study examines the ability to selectively activate different nerve fibers in a finger by using different sinusoidal stimulation frequencies. Specifically, the stimulation of A-beta, A-delta, and C-fibers is looked into, and responses from each of three different stimuli (5 Hz, 250 Hz, and 2000 Hz) are compared. Action potential (AP) responses from the different nerve fibers are simulated. Activation thresholds are determined for each fiber type. The resulting firing frequencies are compared with thresholds found in the literature to determine the stimulating signal amplitude at which sensations begin to be perceived for each stimulation frequency. Results indicate that while selective stimulation of C-fibers and A-beta fibers appears to be possible with 5 Hz and 2000 Hz, respectively, selective stimulation of A-delta fibers may not be possible due to them requiring a higher stimulating signal amplitude to cause the nerve to reach the physiological threshold than A-beta fibers for 250 Hz. Thus, selective stimulation of the three types of nerve fibers may not be possible for all three examined frequencies.