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Skin mechanoreceptors are essential for the vibro-tactile sensory perception. The vibro-tactile perception depends mainly on both fast adapting receptors (Pacini and Meissner's corpuscles) and slow adapting ones (Merkel discs). Vibratory perception in the periphery has different characteristics depending on the skin surface that receives its afferents. From a mechanical point of view, the vibration sinusoid has different characteristics (amplitude and firing frequency), which confer diverse properties and will generate distinguishable features in the vibro-tactile perception. The vibratory stimuli transmission pathway from the periphery to the somatosensory cortex includes four neural relays that retain a somatotopic distribution along the way, and the signal decoding in each relay, preserves its mechanical characteristics. At a cortical level it appears that the secondary somatosensory area (SII) receives afferents mainly from high-frequency mechanoreceptors capable of discriminating primarily the frequency but also the amplitude (pitch) of the vibratory stimulus. Finally it is recognized that a co-activation of both somatosensory and auditory association cortices occurs, and that this co-activation is dependent on the intrinsic properties of the vibration sinusoid (frequency, amplitude and duration) as well as on the environmental feedback. [ABSTRACT FROM AUTHOR]