Thalamocortical neural responses during hyperthermia: A resting-state functional MRI study.

Int J Hyperthermia. 2017 Sep 19;:1-18

Authors: Zhang J, Qian S, Jiang Q, Gong G, Liu K, Li B, Yin Y, Sun G

Abstract
The neural responses during hyperthermia, once thought of as simple physiological processes (e.g. thermal sensation and regulation), have now been recognized involving more cognitive processes, which would be highly of importance to the management of those occupations during heavy heat exposure. Previous studies have demonstrated altered activity in localized subcortical clusters for thermal sensation and regulation, as well as cortical-cortical activity for behavioral tasks during hyperthermia. However, the involvement of cortical-subcortical activity during hyperthermia has not been investigated. In this study, we performed exploratory analyses comparing thalamocortical functional connectivity during whole body hyperthermic condition for an hour at 50°C and normothermic condition at 25°C. We found weakened functional connectivity of cortical fronto-polar/anterior cingulate cortex and prefrontal areas with the corresponding thalamic nuclei during hyperthermic versus normothermic comparisons. On the contrary, the motor/premotor, somatosensory and temporal cortical subdivisions showed increased connectivity with thalamic nuclei during hyperthermia. Thalamocortical connectivity changes in the prefrontal were identified to be correlated with the behavioral reaction time during psychomotor vigilance test after controlling for physiological variables. These distinct thalamocortical pathways alterations might reflect physiologically thermal sensation and regulation, as well as psychologically neural behavior changes underlying cortical-subcortical activity during hyperthermia.

PMID: 28927330 [PubMed - as supplied by publisher]