Perception of tactile stimulation in the fingertip during axon release: assay for peripheral neuropathy

Peripheral neuropathy is a common side effect in individuals with diabetes, in which nerve damage causes a loss of sensation in the extremities. One way to diagnose symptoms of peripheral neuropathy is tactile stimulation. Vibration stimuli on the fingertip at varying frequencies and amplitudes can activate mechanoreceptors underneath the surface of the skin. The change in frequency can activate different types of mechanoreceptors, such as slow adapting or fast adapting Type I or Type II. The slow adapting Type I mechanoreceptors, or Merkel corpuscles, are activated at frequencies less than 15 Hz. The underlying peripheral C fibers, which react to stimuli such as heat, pain, or itching, have been shown to effect the perception of tactile stimulation when activated. C fiber stimulation causes axon reflexes, or neurons, to travel to the peripheral nerves and interfere with the mechanoreceptor response. The goal of this research is to investigate the interaction between mechanoreceptor and C fiber stimulation. The Merkel corpuscles will be stimulated using a vibrating probe at slow frequencies, and the C fiber axon reflex will be achieved using methods such as thermal stimulation on the skin surface. The perception of the vibration stimulus during C fiber activation can help to identify the severity of nerve damage in individuals with peripheral neuropathy.