fMRI study on the impact of passive hyperthermia on the executive control function / 实用放射学杂志

ABSTRACT

Objective To explore the causal influences between activated regions in executive control network when participants were performing attention network test (ANT)under passive hyperthermia using Granger causality analysis.Methods Thirty male healthy participants which were randomly divided into control group (n=1 5)and experimental group (n=1 5)performed ANT task during two thermal conditionshyperthermic condition (50℃)and normothermic condition (20℃)during functional magnetic reso-nance imaging.The data processing was performed using statistical parametric mapping 8 (SPM8).Granger causality analysis was performed on the resulted activated regions,as well as the correlations of the GC values with the reaction time in both groups.Results Between-group comparisons on Granger causality analysis revealed significantly enhanced influences of anterior cingulate gyrus and right inferior parietal lobule on dorsolateral prefrontal cortex,and bidirectional influences between dorsolateral prefrontal cortex and right superior parietal lobule,but decreased influence between right superior parietal lobule and right inferior parietal lobule.The correlation analysis showed significant correlation between GC value of right superior parietal lobule to dorsolateral prefrontal cortex and the reaction time in control group (r=-0.558,P =0.031),but yet there was no significant correlation in experimental group (r=0.355,P =0.257).Conclusion Heat stress affected the causal influences within the executive control network,which subse-quently disrupted the executive control performance during passive hyperthermia.