title: Pain processing by spinal microcircuits: afferent combinatorics.
abstract: Pain, itch, heat, cold, and touch represent different percepts arising from somatosensory input. How stimuli give rise to these percepts has been debated for over a century. Recent work supports the view that primary afferents are highly specialized to transduce and encode specific stimulus modalities. However, cross-modal interactions (e.g. inhibition or exacerbation of pain by touch) support convergence rather than specificity in central circuits. We outline how peripheral specialization together with central convergence could enable spinal microcircuits to combine inputs from distinctly specialized, co-activated afferents and to modulate the output signals thus formed through computations like normalization. These issues will be discussed alongside recent advances in our understanding of microcircuitry in the superficial dorsal horn.
authors.affiliation: Department of Neurobiology and the Pittsburgh Center for Pain Research, University of Pittsburgh, Pittsburgh, PA, United States. prescott@neurobio.pitt.edu
authors.forename: Steven A
authors.initials: SA
authors.lastname: Prescott
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Ratté
mesh_terms: D000200:Action Potentials; D000344:Afferent Pathways / Q000473:pathology*; D000818:Animals; D006801:Humans; D009415:Nerve Net / Q000473:pathology / Q000503:physiopathology*; D009474:Neurons / Q000166:cytology / Q000502:physiology; D010146:Pain / Q000473:pathology*; D013116:Spinal Cord / Q000473:pathology*