rtfMRI-NF技术在抑郁症干预中的应用

Application of rtfMRI-NF Technology in Depression Intervention

rtfMRI-NF(real-time functional magnetic resonance imaging neurofeedback)是将fMRI采集到的血氧信号进行实时处理,并将结果反馈给MRI设备中的被试,训练其增强或减弱特定脑区或脑网络的活动水平。目前多数rtfMRI-NF情绪调节研究主要采用回忆积极记忆的策略实现杏仁核的激活,训练后情绪调节、抑郁症状和行为表现由显著改善,其可能的机制是通过干预增强情绪调节脑区之间的连接。未来研究可采用rtfMRI-NF技术干预抑郁症认知紊乱以及针对脑网络进行干预。

Major depressive disorder(MDD) is characterized by impaired emotion regulation.Real-time functional Magnetic Resonance ImagingNeuro Feedback(rtfMRI-NF) offers a non-invasive technique to train participates to regulate activation of emotion regulation networks.During the scanning,subjects are instructed to regulate their emotions by upregulating or downregulating the activity of the target brain regions or networks.The neural mechanism of successful emotion regulation with rtfMRI-NF in MDD still remains unclear.This study provides a literature review of advantages and limitations of rtfMRI-NF,as well as results of studies using rtfMRI-NF for emotion regulation enhancement from various target brain areas in MDD.The results have shown that rtfMRI-NF can improve emotion regulation ability and reduce depressive symptom.Moreover,during and after intervene within one or several fMRI sessions,MDD patients are able to voluntarily control the activity of their target brain areas,including the amygdala,anterior insula,anterior cingulate cortex and several subregions in PFC.Furthermore,most rtfMRI-NF intervention studies also reported that enhancements of functional connectivity between target regions and other emotion-related brain regions,which might be the neural mechanism of regulating emotion successfully with rtfMRI-NF in MDD.In most studies,participants were required to increase activation of target area by recalling positive memory.Although results have shown that participants can finally control activation of target area by themselves without feedback,less studies reported participants’ depressive symptom during follow-up,which is important to the assessment of intervention effect.Another core symptom of MDD is anhedonia,which is caused by the functional or structural abnormalities in ventral striatum.So far,few rtfMRI-NF intervention studies have taken ventral striatum as a target region to normalize the obvious anhedonia of MDD.Hence,using the brain network activation or connection as neural feedback information might be another effective way to strengthen the ability of emotional regulation.Actually,only a few studies provided feedback of functional connectivity among several regions to help participants to regulate brain activation.Additionally,cognitive deficits of MDD also attracted increasing attention.Existing studies applying rtfMRI-NF intervention in MDD patients were mainly focused on emotion self-regulation training,only a few evaluated cognitive performances after rtfMRI-NF training or directly improved cognitive dysfunction using rtfMRI-NF in MDD.Considering that the prefrontal cortex is a key substrate for both emotional and cognitive control,training MDD to regulate PFC might be helpful not only to enhance the emotion regulation ability,but also to normalize cognitive dysfunction after intervention.Further clinical studies are needed to explore the neural mechanism of NF effect on the relief of symptom in emotional and cognitive domains of depressive disorder.Alternatively,studies aiming to enhance emotion regulation ability in MDD patients can also include assessments of cognitive performances.Given that the achievement of self-regulation with rtfMRI-NF intervention might increase connections among several regions,further studies could select more functional-organized areas together as target regions instead of a single one.In conclusion,the rtfMRI-NF might be another promising clinical intervention,which can robustly decrease the depressive symptoms of patients.