Abstract
Thermal sensation is crucial for homeostasis, guidance of behaviour, and emotion regulation. Thermal afferent pathways are also closely linked with nociceptive pathways, in both the spinal cord and the cortex. Thus, thermal sensations influence the body’s system for detecting and defending itself against environmental threats. Despite the important roles of thermoception in all mammalian life, systematic studies of human thermal sensory systems are rare. This project will apply advanced methods for studying temperature perception to characterise the temporal factors underlying thermoception in humans, over and above established differences in the conduction velocities of the different afferent fibre classes. We will use similar methods to dissect the influences of temperature sensing on pain, by employing a sensory illusion in which mild warm and cool temperatures are combined to produce a sensation of burning pain (i.e., the “Thermal Grill Illusion”). Companion studies in mice will record from spinal and cortical neurons during exposure to thermal stimuli to look for neurophysiological signals associated with the temporal resolution thresholds obtained from our human participants.
References
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