Targeting the Default Mode Network: A TMS-fMRI Study

针对默认模式网络：TMS-fMRI 研究

• 批准号: 10590968
• 负责人: ALLYSON C ROSEN
• 金额: $ 20.36万
• 依托单位: PALO ALTO VETERANS INSTIT FOR RESEARCH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-16 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10590968
• 关键词: Affect; Amygdaloid structure; Anatomy; Anterior; Anxiety; Area; Atlases; Autobiography; Brain; Brain region; Clinical; Clinical Trials; Cognition; Complement; Data; Detection; Disease; Emotional; Evaluation; Fright; Functional Magnetic Resonance Imaging; Goals; Human; Inferior; Insula of Reil; Laboratories; Lead; Learning; Left; Measures; Mediating; Memory; Mental Depression; Moods; Parietal Lobe; Patients; Persons; Physiologic pulse; Post-Traumatic Stress Disorders; Prefrontal Cortex; Process; Protocols documentation; Reporting; Resistance; Rest; Scalp structure; Symptoms; System; Techniques; Testing; Transcranial magnetic stimulation; Veterans; Work; anxiety symptoms; anxiety treatment; blood oxygenation level dependent response; connectome; cranium; emotion regulation; executive function; follow-up; frontal lobe; improved; interest; neuroregulation; novel; response; secondary analysis; support network; symptomatic improvement; treatment response; virtual

PROJECT SUMMARY / ABSTRACT Post-traumatic stress disorder (PTSD) is a devastating illness in which traumatic autobiographical memories are intrusive and lead to anxiety symptoms. These symptoms align with the functions of the default mode network (DMN) and, in fact, PTSD patients have abnormalities within the DMN and in its interactions with other networks, notably the salience network and the frontoparietal or central executive network. Focal repetitive pulse transcranial magnetic stimulation (rTMS) enables neuromodulation of selected brain regions and connected networks to treat specific symptoms, but the brain targets to support this therapy in PTSD are under discovery. A recent analysis uncovered a brain circuit associated with improvement in anxiety and somatic symptoms following the rTMS treatment of depression. The left hemisphere region with the strongest fMRI functional connectivity with this circuit lies within anatomical area 8Av and the DMN. This association suggests that modulating the DMN through stimulation at left 8Av could be a novel rTMS approach for the treatment of anxiety and may help ameliorate anxiety symptoms in PTSD. This target would be novel since the vast majority of clinical trials of rTMS in PTSD have targeted the right frontal regions of the salience and frontoparietal networks instead of the DMN. One potential reason is that the most established nodes of the DMN do not lie directly below the scalp/skull and are thus unreachable by rTMS. In this proposal we test the overall hypothesis that left area 8Av can serve as a robust, direct brain target for the DMN thus facilitating therapy for PTSD and the many other disorders involving the DMN. We propose to use TMS-fMRI in 30 Veterans with PTSD to test the causal connections between left 8Av and other regions that could mediate a response. We will test the connectivity between 8Av and the inferior parietal lobe (IPL), a region in the DMN involved in context processing, and other nodes of the DMN (e.g., posterior cingulate, ventromedial prefrontal cortex). We have pilot data in which we found the functional connection between 8Av and the IPL to be abnormal relative to controls, and also that delivering rTMS to these regions ameliorates anxiety. We will also explore whether stimulation at 8Av modulates the anterior insula, a node of the salience network whose functional connectivity predicts benefit from prolonged exposure therapy in PTSD. We will measure the TMS induced BOLD response in these areas to stimulation of 8Av and compare this response to conventional seed-based resting-state fMRI functional connectivity analyses that could serve as an alternative marker for capacity for modulation. In addition we will deliver thetaburst rTMS stimulation and study how connectivity changes with respect to baseline. Our overall goal is to characterize left 8Av functional connectivity in PTSD, and explore the effects of rTMS stimulation parameters. This project will thus provide a mechanistic understanding of rTMS therapy at 8Av, and will reveal the effects of a novel connectivity-based atlas target.

项目摘要/摘要