Effect Of Neurofeedback Training On Synchronization Of Electroencephalographs Signals In Attention Deficit Hyperactivity Disorder Children

Attention deficit hyperactivity disorder(ADHD)is a common neurological disorder in adolescents and children.Although ADHD drugs can improve patients' attention and impulsive symptoms in a short period of time,there are some problems in drug treatment,such as dose control,loss of appetite,malnutrition and repeated symptoms after drug withdrawal.As a non-pharmacological treatment,neurofeedback training mainly improves the abnormal performance of attention deficit and hyperactivity disorder by autonomously regulating the proportion of rhythm signal energy in EEG.How neural feedback training regulates the imbalance of the electrophysiological activity of the nervous system or neurons and its underlying laws,how to use scientific analysis methods to effectively explore the potential law and its application in the treatment of clinical diseases has great research value.ObjectiveTraditional ADHD diagnosis is based on clinical symptom and cognitive behavioral scale assessments(eg,SWAN scale).The scale assessment has the advantages of rapid diagnosis,intuitive results,simple operation and small cost,but there are problems such as subjective and inaccurate results,large evaluation scales,and lack of objective evaluation of brain function status of ADHD children from the perspective of brain function analysis.EEG analysis can analyze and quantify the impact of neurofeedback training on the nervous system by analyzing EEG signals more accurately and objectively.In this study,phase synchronization analysis and amplitude coherence analysis were used to compare the changes of EEG phase synchronization and coherence in ADHD children before and after neurofeedback training,and to observe the synchronization in different brain regions.Furthermore,the effects and rules of neurofeedback training on synchronization characteristics in children with ADHD were studied.In addition,the feasibility of using EEG synchronization features to reflect the effects of neurofeedback training is discussed,which provides an objective method for quantitative analysis of neurofeedback training effects.Methods 1 Experimental data: Sixteen ADHD children who met the experimental grouping conditions participated in 60 training cycles of neurofeedback training,and 16 healthy children served as control group.2 Experimental data: EEG data of children with ADHD before and after eurofeedback training were collected,while those of healthy children were collected only once as baseline EEG data.3 Behavior Scale Assessment: SWAN Behavior Scale was used to evaluate the cores of ADHD experimental group before and after neurofeedback training.4 EEG pretreatment: The collected EEG was preprocessed to remove artifacts such s power line noise,EMG(electromyogram),EOG(electrooculography)and zero phase shift filtering.5 Phase synchronization analysis: The phase lock value of preprocessed EEG data was calculated by using phase synchronization analysis method.The phase synchronization from m to n of any channel was calculated,and the phase synchronization matrix between any channels is constructed.The phase synchronization between the central lobe and each brain lobes was calculated under different EEG rhythms using C3 and C4 as reference electrodes before and fter neurofeedback.The differences of brain functional coupling before and after eurofeedback with C3 and C4 as reference electrodes were calculated and nalyzed.The coherence differences between the central lobe and each brain lobe under different EEG rhythms with C3 and C4 as reference electrodes before and after neurofeedback training were calculated and analyzed.ResultsAfter theta/beta neurofeedback training,the phase synchronization of theta band between the left hemisphere central lobe and the prefrontal lobe and left middle temporal lobe decreased significantly,while the phase synchronization between the left hemisphere central lobe and the right temporal lobe increased significantly with the tendency to the level of healthy children.Phase synchronization in the frontal,central and right occipital lobes increased significantly in alpha band,but decreased significantly in the left and right temporal lobes.The phase synchronization of the frontal,central,parietal and occipital lobes of ADHD children increased significantly in beta band,while the phase synchronization of the central and left middle temporal lobes decreased,and the phase synchronization of the right temporal lobe increased.After neurofeedback training,the brain function coupling level of ADHD children tended to be normal.The coherence study of EEG showed that theta/beta neurofeedback training also had positive effects on improving the functional coupling of hemispheric EEG in ADHD children.Especially,the coherence of the left and right hemispheres and the frontal,temporal,parietal and occipital lobes of the contralateral hemisphere had positive effects,the excessive delta and theta band coherence of frontal,temporal,parietal and occipital lobes with the central lobe was reduced.Beta band coherence of frontal,parietal,occipital lobe with central lobe was enhanced.The beta band EEG coherence of frontal,parietal,occipital lobes with central lobe was enhanced,which significantly improved the abnormal coupling of brain function in ADHD children,and the brain functional connectivity tended to be healthy.In addition,the SWAN cognitive behavioral scale was used to assess behavioral changes in children with ADHD before and after neurofeedback training.The scores showed that ADHD children's attention deficit and hyperactivity/impulsive symptoms were significantly improved.ConclusionTheta/beta neurofeedback training,as a non-pharmacological treatment,can affect the phase synchronization level of brain regions in children with ADHD and the hemispherical coherence characteristics of children in each band of ADHD.After neurofeedback training,the EEG correlation characteristics are closer to the level of healthy children.It indicates that the brain function coupling abnormality of children with ADHD is improved.In addition,the cognitive behavioral scale assessment results show that ADHD children's external behavioral performance has also improved,making it closer to the level of healthy children.Therefore,phase synchronization analysis and coherence analysis can effectively distinguish ADHD children from healthy children,and can objectively quantify abnormal EEG in ADHD children before and after neurofeedback training,and diagnose and quantify the neurofeedback training effect of ADHD children.In addition,the clinical cognitive behavior scale will be used to comprehensively evaluate the effects of ADHD neurofeedback training.