A finite-element model of mechanosensation by a Pacinian corpuscle cluster in human skin.

Abstract

The Pacinian corpuscle (PC) is the cutaneous mechanoreceptor responsible for sensation of high-frequency (20-1000 Hz) vibrations. PCs lie deep within the skin, often in multicorpuscle clusters with overlapping receptive fields. We developed a finite-element mechanical model of one or two PCs embedded within human skin, coupled to a multiphysics PC model to simulate action potentials elicited by each PC. A vibration was applied to the skin surface, and the resulting mechanical signal was analyzed using two metrics: the deformation amplitude ratio ([Formula: see text], [Formula: see text] and the phase shift of the vibration ([Formula: see text], [Formula: see text] between the stimulus and the PC. Our results showed that the amplitude attenuation and phase shift at a PC increased with distance from the stimulus to the PC. Differences in amplitude ([Formula: see text] and phase shift ([Formula: see text] between the two PCs in simulated clusters directly affected the interspike interval between the action potentials elicited by each PC ([Formula: see text]. While [Formula: see text] had a linear relationship with [Formula: see text], [Formula: see text]'s effect on [Formula: see text] was greater for lower values of [Formula: see text]. In our simulations, the separation between PCs and the distance of each PC from the stimulus location resulted in differences in amplitude and phase shift at each PC that caused [Formula: see text] to vary with PC location. Our results suggest that PCs within a cluster receive different mechanical stimuli which may enhance source localization of vibrotactile stimuli, drawing parallels to sound localization in binaural hearing.