Little was known about neural mechanisms of thermotactile perception. In this project we pinpointed representation of temperature in the central and peripheral nervous system and went on to uncover the cellular encoding schemes. In particular, we have shown that the primary thermal cortex is located in a posterior region of the insular cortex. Despite being at different end of the same sensory axis, we were surprised to find that warm and cool are processed in very different ways in the brain and appear to resemble sub-modalities of the somatosensory system. This is also reflected in perception, where mice, like humans, have different sensory thresholds and response latencies. Our work with mice with knock outs of different sensory ion channels highlighted which thermally sensitive ion channels are involved in thermal perception. We went on to examine the perception and neural encoding features of thermotactile integration and observed an enhancement of perception during multisensory stimulation and have characterized key cortical encoding schemes underlying thermo-tactile integration. Finally, to examine cellular mechanisms of cortical processing, we have examined neurons in living mice that are monosynaptically connected. Paradoxically, we have shown that single action potentials from cortical excitatory neurons can evoke inhibition of surrounding neurons. This type of inhibition is important for the processing of touch and temperature information in the neocortex. Our work has been published in peer reviewed journals and presented at national and international conferences and public science days. Overall, we hope that our work has made fundamental step to an understanding of sensory perception and established the mouse thermotactile system as a good model to understand brain function and dysfunction.
