Objective: To analyze the characteristics of the magnetoencephalography (MEG) and frontal asymmetry in alpha oscillations of teenagers with first-episode major depressive disorder,to explore the electrophysiological mechanism of the occurrence of depressive disorder,and to provide reference for the clinical application of MEG. Methods: Selected the adolescents (13-19 years old) patients with first-episode major depressive disorder from October 2016 to June 2017 in Guangdong 999 brain hospital,and recruited 10 healthy volunteers as a control group.Scanned magnetic fields signals in the brain (Left and right sides of the central area,frontal lobe,temporal lobe,parietal lobe and occipital lobe) from the two groups using the 148-channel MEG system.Calculated and analyzed the spectral power. Results: Compared with the control group,the power of delta band in the left parietal lobe was increased (P<0.05) in the patient groups.The power of theta band in the right temporal lobe and parietal lobe are both increased (P<0.01) in the patient groups.For male patients,the power of delta band in the left parietal lobe was increased more than female patients (P<0.05).Frontal asymmetry in alpha oscillations was not to be proved on MEG (P>0.05). Conclusion: The present study suggests that teenagers with first-episode major depressive disorder have impaired neural activity at many bands,the changes of the power of delta and theta bands might be relevant to teenagers major depressive disorder.
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