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Objective:To analyze the characteristics of gamma oscillation in chronic insomnia patients with anxiety and depression, and to investigate its underlying neural mechanism.Methods:According to the anxiety and depression scores, the subjects with chronic insomnia who met the diagnostic criteria were divided into chronic insomnia with anxiety and depression group ( n=19) and chronic insomnia group ( n=13). Healthy subjects matched with age, gender, and educational background were selected as the normal control group ( n=16). The EEGs from the three groups under resting state and cognitive load state were collected.The relative gamma power was then calculated by fast Fourier transform.The spatial distribution pattern of the gamma oscillation in the three groups was analyzed.Spearman correlation analysis was employed to quantify the correlation between relative gamma powers and sleep scale, anxiety and depression scale scores. Results:In the resting state, the relative gamma power in the chronic insomnia with anxiety and depression, chronic insomnia and normal control group was 0.192 1±0.008 0, 0.210 3±0.009 6, 0.237 3±0.006 4, respectively.In the cognitive load state, the relative gamma power in the three groups increased compared with those in the resting state (0.220 7±0.008 1, 0.249 5±0.009 8, 0.267 7±0.007 2, respectively) (all P<0.05). In the resting state, the relative gamma power (F3, F4, C3, C4, P3, P4, O2, F8, T4) in the chronic insomnia with anxiety and depression group (0.179 9±0.009 7) and the chronic insomnia group (0.194 4±0.010 4) was lower than that in control (0.236 0±0.012 0, P<0.05). In the cognitive load state, the relative gamma power (F3, C3, C4, P3, P4, T4) in the chronic insomnia with anxiety and depression group (0.207 3±0.009 7) was lower than that in control (0.259 1±0.009 4)( P<0.05). There was a significant negative correlation between the relative gamma power in the nodes(F3, C3, P3)and the insomnia, anxiety and depression in the three groups(correlation coefficient r=-0.467--0.274, P<0.05). Conclusion:Chronic insomnia patients with anxiety and depression are often accompanied by cognitive dysfunction.The loss of gamma oscillation in left posterior, left central and left apex may be one of the potential neural mechanisms of cognitive dysfunction in chronic insomnia patients with anxiety and depression.
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Objective To study the characteristics of brain electrical signals in mild cognitive impairment (MCI) patients and healthy elderly volunteers in rest and task loading state.Methods Twenty MCI patients served as a MIC group and 22 sex-,age-and education-matched healthy volunteers served as a control group in this study.The patients were scored according to the MoCA,HADS,MMSE and CMS,their brain electrical signals in a different state were recorded with a digital EEG recording device,and their Lemple-Zie complexity (LZC) was computed on the MATLAB 7.04 platform and comparatively analyzed.Results The MQ value and MoCA,HADS,MMSE,CMS scores were significantly higher in control group than in MCI group (P＜0.01).The LZC value in left frontal region and left temporal region was significantly higher in control group than in MCI group in rest state (0.577±0.059 vs 0.545±0.067,0.576±0.061 vs 0.548±0.059,P＜0.05).The LZC value in right frontal region and right hemisphere was significantly lower in MCI group than in control group in brain electrical activity state (0.535±0.065 vs 0.559±0.033,0.541±0.064 vs 0.551±0.047,P＜0.05).The LZC value in left frontal region,left temporal region,left hemisphere was lower in control group than in MCI group (0.523±0.040 vs 0.547±0.070,0.547±0.048 vs 0.561±0.092,0.542±0.044 vs 0.557±0.067,P＜0.05).Conclusion The LZC value is lost in the left hemisphere but its functional compensation is present in the right and Left parietal lobe,left frontal lobe and right brain areas in MCI patients in a non-linear manner.
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Objective To investigate the Lemple-Zie complexity (LZC) characteristics in patients with Alzheimer' s disease(AD),mild cognitive impairment(MCI) and normal elderly,and the possibility of differentiating AD,MCI and normal elderly by LZC.Methods Electroencephalogram (EEG) of 30 AD patients,30 MCI patients and 20 normal elderly with eyes closed in rest state were recorded.In acquired EEG data,2048 points(10.14 s)of each channel were selected for LZC calculation by Matlab 7.0 software.Results (1) The average LZC values in AD,MCI and control groups were 0.396 ± 0.036,0.470 ±0.051,0.523 ±0.055 respectively.As compared with control group,the values in AD and MCI groups were decreased (F =43.092,P =0.000).(2) LZC values of AD in all channels (from 0.373 ± 0.042 to 0.430 ±0.083),whole brain,bilateral hemispheres,frontal and temporal areas were significantly lower than those in the normal group (from 0.498 ± 0.067 to 0.566 ± 0.059 ; t =3.602-8.747,P =0.000-0.010),and showed the significant decline(＞ 23％)in bilateral anterior middle temporal,frontal areas,the left parietal area.(3) Except the T6 channel,LZC values of AD groups in the remaining channels(from 0.373 ±0.042 to 0.418±0.063),the whole brain,bilateral hemispheres,frontal and temporal areas were significantly lower than those in the MCI group(from 0.455 ± 0.072 to 0.489 ± 0.063 ; in T5 channel,t =2.038,P =0.041,the others t=4.178-7.424,all P=0.000).(4) LZC values of MCI groups in the whole brain,bilateral hemispheres,temporal areas,parietal areas,the left frontal area were notably lower than those in the control group.Conclusions With the decline of the cognitive function,the EEG complexity value shows the parallel change.It suggests that the EEG complexity value can reflect the change of brain function in the duration from normal age to dementia in some degree; The MCI patients with abnormal LZC values in temporal and frontal lobes have a certain degree relation with the occurrence of AD.
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Objective To explore the characteristics of EEG frequency in recruits and veterans and their relationship with depression scale scores.Methods Fifty-five newly enlisted soldiers formed the recruits group and 68 demobilized soldiers the veterans group.A general information survey,EEGs and the Hamilton depression scale (HAMD) were administered to all of the subjects.According to the HAMD scores,35 of the 123 were designated as the abnormal group,while 88 formed the normal one.Eighteen of the 35 with EEG abnormalities served as a doubleabnormal group to be compared with the remaining 17 cases with abnormal HAMD scores and normal EEGs (the single-abnormal group),and 9 of the 18 with higher HAMD scores as the higher group,and the other 9 cases as the lower group.The EEG frequency spectrum and the power percentages from the δ to γ frequency bands were calculated as δ:0.5-4 Hz,(o):4-8 Hz,α:8-13 Hz,β:13-25 Hz,γ:25-40 Hz.Results Forty-six of the subjects (37.4％) had abnormal EEG results,35 had abnormal HAMD scores,and 18 (51.4％ of the soldiers with abnormal HAMD scores) had both abnormalities.The veterans had lower δ band power percentage in all channels than the recruits,but in the (0) band it was the reverse.In the left channels the veterans had lower α and γ band power percentages than the recruits.Compared with the normal,all channels in the EEGs of subjects with abnormal HAMD scores had significantly higher δ band power percentages.The higher the δ band power percentage a subject had,the higher his HAMD score.Conclusion There is some correlation between changes in EEG power percentages and the possibility and severity of depression.Objective and subjective EEG evaluation can help improve the positive rate of diagnosis,and thus the management of the army.
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Objectiye To study the mechanism by which transcranial magnetic stimulation (rTMS) affects cognitive dysfunction in vascular dementia (VD). Methods Thirty-six male Wistar rats were randomly divided into a control group, a VD group, a low frequency rTMS group and a high frequency rTMS group. Two-vessel occlusion was employed to induce VD models. Low frequency rTMS group rats were given 0.5 Hz rTMS for six weeks. High frequency rTMS group rats were given 5 Hz rTMS for six weeks. Morris' water maze test was used to measure their spatial learning ability and memory. The ultrastructures of the synapses in the four groups were detected with transmission electron microscopy. The expression of synaptophysin (SYN), brain derived neurotrophic factor (BDNF) and Nmethyl-D-aspartate receptor 1 ( NMDAR1 ) mRNA and protein in the hippocampus were determined by real-time PCR and Western blotting. Results The behavior and morphology of the rats treated with rTMS improved. The average expression of SYN, BDNF and NMDAR1 mRNA and protein in the low frequency rTMS group and the high frequency rTMS group were significantly higher than in the VD group. Conclusion rTMS can provide a rehabilitative effect for VD. The mechanism might be associated with enhancing the expression of SYN, BDNF and NMDAR1 in the hippocampus.
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Objective To study the therapeutic effects of low frequency repetitive transcranial magnetic stimulation(rTMS)in cranial dystonia.Methods Twenty cranial dystoina patients were treated with low frequency rTMS.Their motor threshold,cortical silent period(CSP)were evaluated before and after the rTMS and after 1,2,6 months as well as the spares and Toronto Western Spasmodic Torticollis Rating Scale(TWSTRS)to evaluate the effects of rTMS in the treatment of cranial dvstonia.Results The patients scored(23.5±14.0)significantly lower after l and 2 months(17.6 ±14.3,18.5±14.2,t=2.632,2.149.both P<0.05).But there was an increasing tendeney of the score after 2 months.The 2-month efficient rate of low-frequency rTMS Was 60%(12/20),yet the long-term effect of rTMS was still to be studied.There was a very significant improvment of relaxed(46.5%±7.3%vs49.9%±9.2%,t=-3.235.P<0.05)and active threshold(40.2%±5.9%/)5 43.9%±8.8%,t=-2.339,P<0.05),prolongation of CSP((96.1±24.5)ms vs(121.6±27.7)ms,t=-7.223,P=0.000).Conclusion The low frequency rTMS is efficient to relieve the clinical symptoms of cranial dystonia.
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Objective To study the effects of repetitive transcranial magnetic stimulation(rTMS) of the supplementary motor area(SMA)on the cortical excitability in patients with Parkinson's disease(PD).Methods Sixteen patients with PD were included in this study.The motor evoked potentials(MEP)and the N30 component of somatosensory evoked potentials(SEP) were assessed for each patient before and after 1200 pulses of rTMS of the SMA at 5 Hz and an intensity of 100% of relaxed motor threshold (RMT) for the abductor pollicis brevis.Results Ten minutes after the rTMS intervention,the peak-to-peak amplitude of the SEP component P20-N30 increased significantly(P<0.05),with the P/F index decreased simultaneously(P<0.05).The MEP amplitude increased significantly,and reached the highest value at 10min after the rTMS intervention. Conclusion 5 Hz rTMS of the SMA can improve the excitability of the SMA itself temporarily.Meanwhile,it can induce a short-lasting facilitation of the excitability of M1 connected with SMA.