Abstract:
When we run our fingers over surfaces to discern their textures, this exploratory movement produces complex vibrations in the skin. Our ability to identify and distinguish textures relies on the spectral analysis of these complex skin vibrations, just as our ability to perceive natural sounds relies on the analysis of acoustic signal contents. Surprisingly little is known regarding how the frequency content of vibrations are encoded and analyzed in the primate brain. In this talk, I will recount our efforts to search for the cortical basis of vibration perception. I will first present the clues revealed by multisensory interactions between touch and audition. I will then describe recently uncovered evidence for vibration frequency tuning in the human brain. Lastly, I will show how we leveraged knowledge about vibration tuning to establish principles underlying bimanual cue integration. Collectively, this work hints at the existence of a somatosensory cortical system dedicated to the encoding and elaboration of environmental vibrations.