Pre-neuronal biomechanical filtering modulates and diversifies whole-hand tactile encoding

When the hand touches a surface, the ensuing contact elicits skin oscillations that travel throughout the hand, driving responses in numerous exquisitely sensitive Pacinian corpuscle neurons (PCs). Although the tuning properties of individual PCs are well-documented, they have been characterized using stimuli applied adjacent to the receptor location. Such experiments are insensitive to the modulating influence of biomechanical filtering, which can significantly alter skin oscillations as they travel through the hand's soft tissues. Here, we used an integrated approach combining vibrometry imaging and computer simulation to characterize the effects of biomechanical filtering on evoked spiking activity in whole-hand PC populations. We observed complex distance- and frequency-dependent patterns of biomechanical transmission arising from the interplay of tissue mechanics and hand morphology. This source of modulation altered the response properties and spike timing of PCs, diversifying evoked activity in whole-hand PC populations. Together, these effects enhanced information encoding efficiency. These findings suggest that the biomechanics of the hand furnishes a pre-neuronal mechanism that facilitates efficient tactile processing. ### Competing Interest Statement The authors have declared no competing interest.