Altered resting-state networks may explain the executive impairment in young health immigrants into high-altitude area.

Abstract

Executive function is a complex involving multiple advanced brain functions like planning, working memory, mental flexibility and psychomotor. Previous researches indicated that executive function may be impaired after acute or chronic high-altitude exposure, while the underlying neurobiological mechanism has not been totally clarified. In the present study, based on 69 young healthy volunteers immigrating to high-altitude, Stroop test was utilized to identify the potential impairment of executive function after two-year high-altitude exposure while resting-state functional MRI (rs-fMRI) technology was employed to observe the alteration of resting-state networks. Stroop test indicated that the subjects experienced significantly lower accuracies and prolonged responding time after two-year exposure. Resting-state network analysis displayed a significantly decreased degree of co-activation within the left/right frontoparietal network, sensorimotor network, and auditory network after exposure. In the frontoparietal network, decreased co-activation intensity was found in left angular gyrus, while in the right frontoparietal network, decreased co-activation intensity was found in left precentral gyrus and postcentral gyrus. Similarly, as for sensorimotor and auditory network, left middle frontal gyrus and left superior temporal gyrus was identified to have decreased co-activation, respectively. Moreover, the responding delays in ST (part II) were negatively correlated with the signal intensity alteration of the right frontoparietal network. All these evidences indicated that the high-altitude exposure induced alteration in above resting state networks may be the functional basis of executive control impairment.