Effects of whole body skin cooling on human cognitive processing: a study using SEPs and ERPs.

The present study investigated the effect of whole body skin cooling on somatosensory ascending processing by utilizing somatosensory-evoked potentials (SEPs) and motor execution, as well as inhibitory processing by event-related potentials (ERPs). Fourteen healthy participants wearing a water-perfused suit performed two sessions (sessions 1 and 2) consisting of SEPs and ERPs with somatosensory Go/No-go paradigms under two conditions (cold stress and control) on different days. In session 2, under the cold stress condition, whole body skin cooling was achieved by circulating 20°C water through the suit for 40 min, whereas 34°C water was perfused in the other sessions. The mean skin temperature decreased from 35.0 ± 0.5°C (session 1) to 30.4 ± 0.9°C (session 2) during whole body skin cooling, but the internal temperature was maintained. Whole body skin cooling delayed the peak latencies of N20, P25, and P45 components at C4' of SEPs (all: P < 0.05). Moreover, the peak latencies of P14, N18, and P22 components at Fz of SEPs and the Go-P300 component of ERPs were delayed (all: P < 0.05). In contrast, the peak amplitudes of all individual components of SEPs as well as N140 and P300 of ERPs remained unchanged. These results suggest that passive whole body skin cooling delays neural activities on somatosensory processing and higher cognitive function.