Summary: | 碩士 === 國立陽明大學 === 神經科學研究所 === 100 === Transcranial magnetic stimulation (TMS)-based therapy proliferates among patients with depression, especially repetitively apply high-frequency pulses over left dorsolateral prefrontal cortex (DLPFC) is believed to have greater antidepressant effect. Like other interventions, however, some depressed patients respond well while others do not. In order to figure out the changes of neural mechanism that accompany symptoms progress after intervention and to identify potential predictors of treatment response that might help improve effective intervention selection. Therefore, we use resting-state fMRI which is a novel informative method for assessing large-scale intrinsic brain activities at a resting state when no task is performed to investigate brain networks differences in patients with treatment-resistant depression (TRD). Twenty-nine patients underwent 2-week high frequency left DLPFC TMS intervention (17 TMS responders (Rs), defined by having 50% or more depression score improvement after treatment, and 12 non-responders (NRs), defined by having less than 50% depression score improvement) were evaluated for pre-/post-treatment resting-state functional connectivity (rs-FC) and fractional amplitude of low frequency fluctuation (fALFF), and compare with 18 healthy comparison subjects. In our results, depressed patients had generally decreased connectivity within limbic-thalamo-cortical circuit. Before treatment, Rs showed significantly decreased rs-FC in emotional regulation circuits and particularly reduced DLPFC-amygdala connection, and increased within emotional regulation and reward-related circuits after treatment. In the meanwhile, NRs showed mainly decreased rs-FC within default mode network and cognitive control circuits at baseline, and increased within default mode network as well after treatment. These results suggested that responses to TMS were characterized by distinct functional deficits in the distributed brain network. Different brain networks were modulated by the same treatment protocol which means both the research and application of TMS may informs us a great value of information about the interaction within brain networks in the future. However, further investigations are needed to verify whether current findings could be treated as a reference for intervention selection.
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