Affiliated with Université Laval & CERVO Research Centre

Sensory Afferents Use Different Coding Strategies for Heat and Cold.

TitleSensory Afferents Use Different Coding Strategies for Heat and Cold.
Publication TypeJournal Article
Year of Publication2018
AuthorsWang F, Bélanger E, Côté SL, Desrosiers P, Prescott SA, Côté DC, De Koninck Y
JournalCell Rep
Date Published2018 May 15

Primary afferents transduce environmental stimuli into electrical activity that is transmitted centrally to be decoded into corresponding sensations. However, it remains unknown how afferent populations encode different somatosensory inputs. To address this, we performed two-photon Ca imaging from thousands of dorsal root ganglion (DRG) neurons in anesthetized mice while applying mechanical and thermal stimuli to hind paws. We found that approximately half of all neurons are polymodal and that heat and cold are encoded very differently. As temperature increases, more heating-sensitive neurons are activated, and most individual neurons respond more strongly, consistent with graded coding at population and single-neuron levels, respectively. In contrast, most cooling-sensitive neurons respond in an ungraded fashion, inconsistent with graded coding and suggesting combinatorial coding, based on which neurons are co-activated. Although individual neurons may respond to multiple stimuli, our results show that different stimuli activate distinct combinations of diversely tuned neurons, enabling rich population-level coding.

Alternate JournalCell Rep
PubMed ID29768200