Warm hands, cold heart: progressive whole‐body cooling increases warm thermosensitivity of human hands and feet in a dose‐dependent fashion

Abstract

Edited by: Paul Fadel New Findings r What is the central question of this study?Investigations on inhibitory/facilitatory modulation of vision, touch and pain show that conditioning stimuli outside the receptive field of testing stimuli modulate the central processing of visual, touch and painful stimuli. We asked whether contextual modulation also exists in human temperature integration. r What is the main finding and its importance?Progressive decreases in whole-body mean skin temperature (the conditioning stimulus) significantly increased local thermosensitivity to skin warming but not cooling (the testing stimuli) in a dose-dependent fashion. In resembling the central mechanisms underlying endogenous analgesia, our findings point to the existence of an endogenous thermosensory system in humans that could modulate local skin thermal sensitivity to facilitate thermal behaviour.Although inhibitory/facilitatory central modulation of vision and pain has been investigated, contextual modulation of skin temperature integration has not been explored. Hence, we tested whether progressive decreases in whole-body mean skin temperature (T sk ; a large conditioning stimulus) alter the magnitude estimation of local warming and cooling stimuli applied to hairy and glabrous skin. On four separate occasions, eight men (27 ± 5 years old) underwent a 30 min whole-body cooling protocol (water-perfused suit; temperature, 5°C), during which a quantitative thermosensory test, consisting of reporting the perceived magnitude of warming and cooling stimuli (±8°C from 30°C baseline) applied to the hand (palm/dorsum) and foot (sole/dorsum), was performed before cooling and every 10 min thereafter. 101 Contextual modulation of skin temperature integration stimuli, in a dose-dependent fashion. In highlighting a novel feature of human temperature integration, these findings point to the existence of an endogenous thermosensory system that could modulate local skin thermal sensitivity in relationship to whole-body thermal states.

Thermosensory mapping of skin wetness sensitivity across the body of young males and females at rest and following maximal incremental running

“…Finally, we have recently demonstrated that changes in whole‐body thermal state can modulate local thermal sensitivity (Filingeri et al . ) and so it cannot be excluded that exercise‐induced changes in mean T sk and T core could have also shifted local thermal sensitivity (Cabanac et al . ).…”

Afferent thermosensory function in relapsing–remitting multiple sclerosis following exercise‐induced increases in body temperature

“…22ᵒC) recorded in our CTR group. Furthermore, we recently discovered that whole-body thermal stress modulates local skin thermosensitivity in healthy adults (Filingeri et al, 2017a) via central mechanisms similar to those underlying endogenous analgesia (Ossipov et al, 2010). Hence, it cannot be excluded that an interaction between pathological (i.e.…”

“…During this session, we used a novel quantitative sensory testing paradigm to assess perceived magnitude of cold and warm temperature stimuli applied to the dorsum of the hand. Our novel quantitative sensory test of afferent thermosensory function is based on the one we recently developed and tested in healthy individuals to assess the effects of whole-body thermal stress on local skin thermosensitivity (Filingeri et al, 2017a) .…”

“…The aim of this study, therefore, was to assess afferent thermosensory function in MS in conditions of exercise-induced increase in body temperature (in the range of what is shown to induce heat sensitivity, i.e. ß0.5°C; Davis et al 2010) using a new quantititave sensory testing protocol (Filingeri et al 2017a). We hypothesized that exercise-induced increase in body temperature would reduce cold (served by myelinated fibres), but not warm (served by non-myelinated fibres), local skin thermosensitivity in relapsing-remitting MS patients compared with age-matched healthy individuals.…”

“…Δ~0.5°C) (Davis et al, 2010) using a novel quantitiave sensory testing paradigm (Filingeri et al, 2017a). We hypothesized that exercise-induced increases in body temperature would reduce cold (served by myelinated fibers), but not warm (served by non-myelinated fibers), local skin thermosensitivity in relapsing-remitting MS patients compared to age-matched healthy individuals.…”