Head and Neck Warming Applied in Thermoneutral Conditions Improves Thermal Sensation but does Not Alter Cognitive Function

Abstract

Background. Heat therapy is widely used for therapeutic purposes in health SPA resorts or hospitals. However,
its  benefits  and  consequences  are  not  strongly  evidenced  and  it  is  partially-related  with  a  lack  of  experimental
information. No one has explored how continuous head and neck warming applied in thermoneutral environment
can affect body temperatures, subjective sensations and cognition and the purpose of this study was to investigate it.
Methods.  Seven  subjects  (21  ±  1  years)  participated  in  two  experimental  trials:  CON  –  control  trial;  and
CONW – head and neck warming trial. These trials were designed to introduce the effects of continuous head and
neck warming (surface warming by 44 ± 1°C) on thermal sensations, body temperatures and cognitive function in
thermoneutral environment (24°C and 60% relative humidity). In each trial body temperatures (rectal, Tre; mean
skin, Tsk), heart rate (HR) response, ratios of subjective sensations (SS) and cognitive function were assessed.
Results. Head and neck warming (CONW trial) maintained significantly higher Tre and Tsk values (by 0.2 ±
0.1°C and 1 ± 0.3 °C, respectively), compared to the control (CON) trial. Head and neck warming caused significant
increment in heart rate (8 ± 2 b/min) and improved thermal sensation (p < .05), but had no effect on shivering/
sweating sensation and thermal comfort. Moreover, head and neck warming (CONW trial) does not induce any
significant impact on accuracy (p > .05) and response times (p >.05) in mathematical and spatial processing tasks.
Conclusions. Continuous head and neck warming applied in thermoneutral conditions maintains higher internal
(Tre) and peripheral (Tsk) body temperatures and improves thermal sensation, but does not alter cognitive function.

Keywords: head and neck warming, subjective sensations, body temperature, cognitive function.