Thalamocortical and corticocortical interactions in the somatosensory system.

Publisher Summary The classic feedforward model of touch provided a fundamental blueprint for the development of somatosensory research in the past five decades, a variety of experimental findings, and theoretical arguments demonstrate that, this model no longer offers an accurate description on how tactile perception emerges in the mammalian brain. Anatomical, physiological, and computational arguments favor the hypothesis that tactile perception emerges through interactive and recurrent interactions between multiple cortical and subcortical levels that define the mammalian somatosensory system. Central to this recurrent model of touch is the experimental demonstration that the massive corticofugal projections, that originate in the neocortex and reach most of the subcortical structures that form the somatosensory system, may play as relevant a role in tactile information processing as the parallel feed forward pathways of this system.