An operant temperature sensory assay provides a means to assess thermal discrimination

Abstract

Mouse behavioral assays have proven useful for the study of thermosensation, helping to identify receptors and circuits responsible for the transduction of thermal stimuli and information relay to the brain. However, these methods typically rely on observation of behavioral responses to various temperature stimuli to infer sensory ability and are often unable to disambiguate innocuous thermosensation from thermal nociception or to study thermosensory circuitry which do not produce easily detectable innate behavioral responses. Here we demonstrate a new testing apparatus capable of delivering small, rapid temperature change stimuli to the mouse’s skin, permitting the use of operant conditioning to train mice to recognize and report temperature change. Using this assay, mice that were trained to detect a large temperature change were found to generalize this learning to distinguish much smaller temperature changes across the entire range of innocuous temperatures tested. Mice with ablated TRPV1 and TRPM8 neuronal populations had reduced ability to discriminate temperature differences in the warm (>35°C) and cool (<30°C) ranges, respectively. Furthermore, mice that were trained to recognize temperature changes in only the cool, TRPM8-mediated temperature range did not generalize this learning in the warm, TRPV1-mediated range (and vice versa), suggesting that thermosensory information from the TRPM8- and TRPV1-neuronal populations are perceptually distinct.

Sensory Integration Disorders in Patients with Multiple Sclerosis

“…It may be hypothesised that patients with decreased sensory discrimination have a greater susceptibility to the onset of relapse [ 41 ]. This hypothesis may also be supported by the fact that the level of sensory discrimination changes in temperature between 30–60 °C [ 42 ]. In patients with MS, increased disease activity occurs during spring and summer.…”

Regulation of transient receptor potential channels by traditional Chinese medicines and their active ingredients

“…In addition, the four qi theory has important guiding significance for rational use of TCM in clinic ( Ma et al, 2020 ; Zhu et al, 2021 ) The transient receptor potential (TRP) family mediates the sensations of heat, cold and pain and an understanding of its function can in turn enhance understanding of the pathophysiological regulation of body temperature or pain relief. It is also one of the molecular bases for an in-depth understanding of the cold-hot theory of TCM, and it provides a basis for studying the cold-hot natures of TCM ( Gao et al, 2014 ; Hung and Tan, 2018 ; Viana, 2018 ; Isaacson and Hoon, 2021 ).…”