Objective Previous studies have suggested that bilateral 5-Hz microcurrent stimulation has a hypnotic effect,but the lack of evidence on how the stimulation affects subjects'sleep limits the validation of this intervention.To address this gap,a crossover experimental design was employed,recruiting both insomnia and non-insomnia subjects.Methods 10 participants with insomnia and 10 healthy participants were selected to attend our study.In this crossover study,true(5 Hz)vs.sham stimulation was applied over the parietal temporal lobes.Impact of stimulation on subjective sleep experience,sleep efficiency,sleep structure and psychomotor vigilance task(PVT)was assessed.Results Subjects who received the true 5-Hz stimulation before bedtime had significantly enhanced sleep efficiency,sleep quality,and mental state compared to the night of sham stimulation.Additionally,subjects who received true stimulation exhibited higher sleep efficiency and a later appearance of dream sleep.These findings suggest that 5-Hz microcurrent stimulation before bedtime can enhance both objective and subjective sleep efficiency.Conclusion 5 Hz microcurrent stimulation before bedtime improved sleep efficiency of subjects and also enhanced their subjective perception of sleep.

Objective To measure the effects of 72 h-isolation and confinement (IC)with or without sleep deprivation (SD)on attention network functions and operation performance of manual controlled rendezvous and docking task. Methods Twelve healthy male volunteers were randomly divided into 4 groups of 3.The experiments were done by means of self-control and cross-over design. Two groups underwent 72 h IC without SD,and then recovered for 7 d.After that,they underwent 72 h IC with SD.Other 2 groups underwent the identical environments in the opposite order.The evaluation of attention network functions and the functional nuclear magnetic resonance examination of brain were conducted before and after isolation.The operation performance of manual controlled rendezvous and docking task was tested during isolation.Meanwhile, the functional magnetic resonance imaging (fMRI)technology was used to evaluate the autonomic activity in the brain region. Results ①The volunteers, average reaction time, accuracy and omission rates of the attention network function test in 72 h IC had insignificant differences as compared with those before the isolation (P>0.05).The 72 h IC and SD caused average reaction time and omission rate evidently increased (t=2 .505 ,2 .3 24,P<0.05 ).For average reaction time,the main effect of test condition was obvious (F=6.725,η2=0.657,P<0.05),so as the mutual effects of test time and test condition for omission rate (F=6.057,5.906,η2=0.612,0.601,P<0.05).For accuracy rates,all three effects were not obvious (P>0.05).②The fMRI data indicated that the spontaneous nervous activity in right frontal eye field was significantly weakened by IC and SD (t=6.580,P<0.05 ),but the activities in 3 clustering fields of right temporal lobe joint were significantly enhanced (t=6.726, 4.905,8.305,P<0.05).③As compared with those in IC condition,the volunteers, success rate of manual controlled rendezvous and docking task in IC plus SD condition was evidently decreased (χ2=9 .7 6 1 ,P<0.0 1 ),but the fuel consumption,pitch angle deviation and yaw angle deviation were significantly increased (t=3 .47 5 ,3 .1 6 1 ,3 .3 7 5 ,P<0.0 1 )and the docking time was significant shortened (t=2 .6 8 1 ,P<0.0 1 ). Conclusions 72 h IC and SD has negative effects on attention network function and operation performance of manual controlled rendezvous and docking task.Sleep deprivation would be the main factor.

Objective To measure the effects of 72 h-isolation and confinement (IC)with or without sleep deprivation (SD)on attention network functions and operation performance of manual controlled rendezvous and docking task. Methods Twelve healthy male volunteers were randomly divided into 4 groups of 3.The experiments were done by means of self-control and cross-over design. Two groups underwent 72 h IC without SD,and then recovered for 7 d.After that,they underwent 72 h IC with SD.Other 2 groups underwent the identical environments in the opposite order.The evaluation of attention network functions and the functional nuclear magnetic resonance examination of brain were conducted before and after isolation.The operation performance of manual controlled rendezvous and docking task was tested during isolation.Meanwhile, the functional magnetic resonance imaging (fMRI)technology was used to evaluate the autonomic activity in the brain region. Results ①The volunteers, average reaction time, accuracy and omission rates of the attention network function test in 72 h IC had insignificant differences as compared with those before the isolation (P>0.05).The 72 h IC and SD caused average reaction time and omission rate evidently increased (t=2 .505 ,2 .3 24,P<0.05 ).For average reaction time,the main effect of test condition was obvious (F=6.725,η2=0.657,P<0.05),so as the mutual effects of test time and test condition for omission rate (F=6.057,5.906,η2=0.612,0.601,P<0.05).For accuracy rates,all three effects were not obvious (P>0.05).②The fMRI data indicated that the spontaneous nervous activity in right frontal eye field was significantly weakened by IC and SD (t=6.580,P<0.05 ),but the activities in 3 clustering fields of right temporal lobe joint were significantly enhanced (t=6.726, 4.905,8.305,P<0.05).③As compared with those in IC condition,the volunteers, success rate of manual controlled rendezvous and docking task in IC plus SD condition was evidently decreased (χ2=9 .7 6 1 ,P<0.0 1 ),but the fuel consumption,pitch angle deviation and yaw angle deviation were significantly increased (t=3 .47 5 ,3 .1 6 1 ,3 .3 7 5 ,P<0.0 1 )and the docking time was significant shortened (t=2 .6 8 1 ,P<0.0 1 ). Conclusions 72 h IC and SD has negative effects on attention network function and operation performance of manual controlled rendezvous and docking task.Sleep deprivation would be the main factor.

Objective:To investigate the moderating role of emotional expressivity in the relationship between test anxiety and working memory capacity (WMC).Methods:Totally 332 college students were selected.The Test Anxiety Inventory (TAI),Emotional Expressivity Inventory (EEI) and Arithmetic Operation-Word Memory Span Task (OSPAN) were used to measure the severity of test anxiety,working memory capacity,and degree of emotional expressivity,respectively.Results:TAI scores were negatively correlated with WMC scores (r =-0.36,P ＜0.01).Emotional expressivity had a moderating effect between scores of test anxiety and WMC (β =0.19,P ＜0.01).Test anxiety score negatively predicted WMC score in students with low emotional expressivity (β =-0.74,P ＜ 0.01),whereas it couldn't predict WMC in those with high emotional expressivity (β =-0.07,P ＞0.05).Conclusion:It suggests that higher emotional expressivity could buffer the negative effect of test anxiety on working memory capacity.

As an important component of the event related potential (ERP), late positive potential (LPP) is an ideal component for studying emotion regulation. This study was focused on processing and analysing the LPP component of the emotional cognitive reappraisal electroencephalogram (EEG) signal. Firstly, we used independent component analysis (ICA) algorithm to remove electrooculogram, electromyogram and some other artifacts based on 16 subjects' EEG data by using EGI 64-channal EEG acquisition system. Secondly, we processed feature extraction of the EEG signal at Pz electrode by using one versus the rest common spatial patterns (OVR-CSP) algorithm. Finally, the extracted LPP component was analysed both in time domain and spatial domain. The results indicated that (1) From the perspective of amplitude comparison, the LPP amplitude, which was induced by cognitive reappraisal, was much higher than the amplitude under the condition of watching neural stimuli, but lower than the amplitude under condition of watching negative stimuli; (2) from the perspective of time process, the difference between cognitive reappraisal and watching after processing with OVR-CSP algorithm was in the process of range between 0.3 s and 1.5 s; but the difference between cognitive reappraisal and watching after processing with averaging method was during the process between 0.3 s and 1.25 s. The results suggested that OVR-CSP algorithm could not only accurately extract the LPP component with fewer trials compared with averaging method so that it provided a better method for the follow-up study of cognitive reappraisal strategy, but also provide neurophysiological basis for cognitive reappraisal in emotional regulation.
Algorithms ; Artifacts ; Cognition ; Electroencephalography ; Electromyography ; Emotions ; Evoked Potentials ; Humans

The robust extracting of evoked potential (EP) has become a vexed question in the process of electroencephalogram owing to the faint signal-to-noise ratio of EP. This paper presents the single trial of EP in time, transform and space field. Several methods such as adaptive filter, wavelet transform, principal component analysis (PCA) and independent component analysis (ICA) have been applied to the process of EP.
Algorithms ; Brain ; physiology ; Electroencephalography ; methods ; Evoked Potentials ; Humans ; Principal Component Analysis ; Signal Processing, Computer-Assisted