Introduction
CIVD, cold injury, paraplegia, heat loss
HEAT, COLD, PARAPLEGIA
Exposure to a cold stimulus causes vasoconstriction of the cutaneous vasculature to reduce heat loss (Tyler et al. It has been proposed that the purpose of the CIVD response may be cryoprotective, that is to minimize the risk of cold injury (Daanen and Ducharme The CIVD response is characterized primarily by the magnitude of the skin temperature (Accordingly, the aim of this study was to examine physiological and perceptual parameters related to CIVD in the fingers and toes of people with paraplegia and compare them with responses observed in able-bodied individuals during exposure to cool, thermoneutral, and hot environments. We reasoned that a predominantly neurally mediated CIVD response would rely on the thermal afferent information emanating from the cutaneous cold sensors and the subsequent centrally mediated thermoeffector drive to the peripheral cutaneous vasculature. A lesion in the spinal cord above the level at which afferent and efferent nerves for a given region enter and exit the spinal cord, respectively, would abolish the neural traffic (Price and Trbovich Accordingly, in this study, we examined physiological and perceptual parameters during cold water immersions in people with paraplegia and able-bodied individuals with the aim to investigate the origin of the CIVD response, namely whether it is central or peripheral. Under the assumption that paraplegic participants have no central control over blood vessels under the level of lesion, the CIVD reactions in paraplegic and able-bodied participants were investigated during exposure to different environmental conditions, resulting in different levels of heat content, since body heat content is known to significantly influence CIVD reactions (Daanen and Ducharme 