Analysis Of Event-related Potential And Source Location Based On EEG Data Of Depression

Depression is the most serious mental illness that endangers human health.Its main symptoms are low mood,loss of interests and motivation diminished.World Mental Health found that the number of people with depression increased year by year.It is expected that depression will become the second leading cause of disease by2020,and the age of onset is getting earlier and earlier.At present,the diagnosis of depression still rely on the doctor’s subjective clinical judgment,because the etiology of depression is still uncertain,thus misdiagnosis rate is high,and depression is not easy to find in early stage.So the urgent need is to find the cause of depression and an accurate diagnosis method.Event-related potential(ERP)is a special brain evoked potential,which is a "window" of mental activity by intentionally giving a stimulus to a particular psychological meaning.It is a safe and convenient detection method,with a high time resolution,simplicity,and portable characteristics.In this paper,the emotional Stroop paradigm is used to evoke event-related potentials.20 depression patients and 20 normal people participated in our experiment.The superposition and the average method are used to obtain evoked potentials,and further to analyze the N1,P200 components expressed by the cognitive function and depression may exist in the depressive disorder.Using EEG signals source location technique to locate the induced components of depressed patients,in turn to analyze the abnormal regions of the brain.The purpose of this paper is to analyze the causes of depression and to provide theoretical support for the diagnosis and treatment of depression.The main work of this paper is as follows:(1)Statistical analysis of behavioral data of depressive patients;(2)Analysis of P200 components associated with selective attention,found negative emotional bias in depressed patients;(3)Analysis of abnormal brain regions which is related to P200 using sLORETA.It is found that thecognitive impairment of depressed patients is mainly in the left frontal lobe and right temporal regions.By analyzing behavior data and ERP components,we found that the response time of depression was significantly increased,and the amplitude of P200 was higher than normal controls,but there was no significant difference in latency.The results of sLORETA showed that depressive patients’ activity was decreased,but the activity of right frontal lobe and temporal lobe was increased.The above results showed that depressed patients had a bias towards negative emotions,and disregard positive emotions.Depressed patients were difficult to control their emotions because of damage of temporal lobe.The above conclusions can be effective in helping the doctor to carry out treatment.