Tactile sensing of surface features

The tactile recognition of an object held in the hand involves characterizing its surface features. Recent neurophysiological studies point to a number of possible ways in which tactile primary afferents convey information about surface characteristics. The spatial pattern of the afferents that are activated probably underlies the unique recognition of patterns. Measures of afferent response intensity correlate well with overall surface texture and quantitatively encode variations in surface spatial parameters. The temporal patterns of afferent firing provide yet another potential mechanism by which surface features are signaled. Studies of somatosensory cortex have already begun to examine the central processing of these afferent signals, and this remains a fertile field for the future.