Objective:To explore the impact of total sleep deprivation (TSD) on executive control function.Methods:Thirteen healthy young men completed visual Go/No-go task before and after the 36 hour sleep deprivation.Functional magnetic resonance imaging (fMRI) was carried out in these subjects 3 weeks apart.Results: The hit rate of Co/No-go task decreased (P

Objective To explore the effect of sustained performance on EEG approximate entropy (ApEn).Methods Fifty participants were divided into two groups according to whether they had undergone sustained performance .One day af-ter the sustained-performance group finished executing their task , the resting EEG of nine electrodes ( F3, Fz, F4, C3, Cz, C4, P3, Pz and P4) was acquired in two grups separately , and the ApEn of each electrode was calculated as well . Results The ApEn of F3 and Fz showed an evident decrease as well as randomness of spontaneous brain electrode activity in frontal lobes , especially in the left one .Conclusion The drop of ApEn and the asymmetry of frontal lobes might reflect participants′state of fatigue during sustained performance .

Purpose To observe the impact of sleep deprivation (SD) for 24 hours on human brain regional homogeneity (ReHo) by using functional magnetic resonance imaging (fMRI),and briefly discuss the intervening effect of transcranial direct current stimulation (tDCS) on ReHo after SD.Material and Methods Sixteen healthy individuals were enrolled,and self-controlled study were adopted.Resting-state fMRI scans were performed in wakefulness,after SD,and after tDCS (true or placebo stimuli).The ReHo analysis approach was employed to calculate the ReHo values of whole brain in different states.The differences between before and after SD,and between true and false tDCS after SD,were analyzed.Results Compared with wakefulness,SD mainly enhanced ReHo in brain regions of left precentral gyrus,right precentral gyrus,bilateral temporal lobe and thalamus,but decreased ReHo in brain regions of right precuneus,left superior occipital gyrus,limbic lobe and bilateral angular gyrus,superior frontal gyrus,middle frontal gyrus.Compared with placebo stimuli,the true tDCS enhanced ReHo in brain regions of bilateral precuneus,angular gyrus and right forehead,superior middle gyrus,but decreased ReHo in brain regions of the medial side of left frontal lobe,right precentral gyrus,parahippocampal gyrus,substantia nigra and bilateral temporal lobe,pons and so on.Conclusion SD can cause ReHo change in a large number of brain regions.The tDCS on the prefrontal cortex improves the brain regions with ReHo reduction caused by SD.The improved brain regions mainly include bilateral precuneus/posterior cingulate cortex.Therefore,tDCS on the prefrontal cortex can improve brain dysfunction caused by SD.