Causal Dynamics of Human Amygdala-Prefrontal Circuits During Fear Extinction Learning
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 40
- 试验地点
- 1
- 主要终点
- Broadband high-frequency power (70-170 Hz) in amygdala-prefrontal circuits
研究概览
简要总结
The goal of this clinical trial is to understand how brain circuits involving the amygdala and prefrontal cortex contribute to fear learning and extinction. Fear extinction is the process by which a fear response decreases when a threat is no longer present. The study will include participants with epilepsy who are undergoing stereoelectroencephalography (SEEG) monitoring as part of their clinical care. The main questions this study aims to answer are: How do the amygdala and prefrontal cortex interact during fear learning and extinction? Do different parts and hemispheres of the amygdala have different roles in fear learning and extinction? How does electrical stimulation of the amygdala affect these brain circuits and fear extinction? Participants will complete tasks involving fear learning and extinction while researchers record brain activity from clinically implanted electrodes. Researchers will also use electrical stimulation via these electrodes to study how amygdala activity affects other brain regions and fear extinction.
详细描述
The ability to reduce fear responses through extinction when threats are no longer present is essential for mental health. Deficits in extinction underlie fear-related disorders such as post-traumatic stress disorder (PTSD). A critical gap remains in understanding the neural mechanisms underlying fear extinction, which poses a major barrier to developing more effective therapeutic interventions. The amygdala (AMY)-prefrontal circuits are critical in fear extinction. In animal models, the lateral nucleus of the amygdala (LA) receives sensory inputs and initiates fear learning, while the basal nucleus of the amygdala (BA) integrates regulatory inputs from the ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortex (dACC) for appropriate fear response. However, due to species-specific differences between animal and human neurobiology, the nucleus-specific contributions of the amygdala and their interactions with the vmPFC and dACC in human fear extinction and regulation remain poorly understood. Clinically indicated stereoelectroencephalography (SEEG) electrodes, which allow direct recording and stimulation of amygdala-prefrontal circuits, provide a unique opportunity to address this gap. The objective of this study is to determine the causal dynamics of amygdala-prefrontal circuits involved in fear extinction learning in participants with epilepsy undergoing SEEG monitoring. The study will address three aims: (1) Determine the intrinsic and stimulation-induced dynamics of human amygdala-prefrontal circuits. The study will characterize cause pathways and circuit-level interactions in amygdala-vmPFC-dACC circuits using intracranial recordings and electrical stimulation. (2) Characterize nucleus-specific and hemispherical lateralized dynamics of amygdala-prefrontal circuits during fear extinction. The study will examine the neural dynamics of the LA, BA, and left and right amygdala-prefrontal circuits during fear extinction and regulation. (3) Determine the effects of theta-burst stimulation of amygdala nuclei on fear extinction. Theta-burst stimulation will be applied to the LA and BA during extinction learning to examine how targeted stimulation modulates fear-related neural circuits and behavior.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •At least 18 years of age.
- •Able to understand the nature of the task.
- •Able to provide informed consent themselves or provide consent through their legally authorized representative.
- •Undergoing clinically indicated intracranial electrode implantation with coverage of at least one fear-related brain region, including the amygdala, hippocampus, cingulate cortex, insula, or prefrontal cortex.
排除标准
- •Under the age of
- •Unable to understand the nature of the task.
- •Unable to provide informed consent themselves or provide consent through their legally authorized representative.
- •No clinically indicated intracranial electrode coverage in any fear-related brain region, including the amygdala, hippocampus, cingulate cortex, insula, or prefrontal cortex
研究组 & 干预措施
Amygdala-prefrontal in Fear Extinction
Participants will undergo direct intracranial electrical stimulation and complete a Pavlovian fear conditioning and extinction task while neural activity is recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes. Electrical stimulation, including single-pulse and/or high-frequency stimulation, will be delivered through the intracranial electrodes to investigate amygdala-prefrontal circuit dynamics. Participants may also receive theta-burst stimulation of the amygdala during extinction learning.
干预措施: Direct intracranial electrical stimulation (Other)
Amygdala-prefrontal in Fear Extinction
Participants will undergo direct intracranial electrical stimulation and complete a Pavlovian fear conditioning and extinction task while neural activity is recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes. Electrical stimulation, including single-pulse and/or high-frequency stimulation, will be delivered through the intracranial electrodes to investigate amygdala-prefrontal circuit dynamics. Participants may also receive theta-burst stimulation of the amygdala during extinction learning.
干预措施: Fear conditioning (Behavioral)
结局指标
主要结局
Broadband high-frequency power (70-170 Hz) in amygdala-prefrontal circuits
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Broadband high-frequency power (70-170 Hz) will be quantified from local field potentials recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes in the amygdala and prefrontal cortex. Broadband high-frequency power will be assessed during fear processing and during intracranial electrical stimulation to characterize local neural activity within amygdala-prefrontal circuits. For stimulation recordings, stimulation artifacts will be removed using appropriate artifact-removal methods, for example, MPARRM (matching pursuit-based artifact reconstruction and removal method) for single-pulse stimulation and LIBRA (linear baseline-integrated removal of artifacts) for high-frequency stimulation.
Oscillatory power at the stimulation frequency during intracranial electrical stimulation
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Oscillatory power at the stimulation frequency will be quantified from local field potentials recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes in the amygdala and prefrontal cortex. Power at the stimulation frequency will be assessed during intracranial electrical stimulation to quantify stimulation-induced oscillatory entrainment within amygdala-prefrontal circuits. For theta-burst stimulation, theta-band activity (4-8 Hz) will be assessed.
Amplitude of cortico-cortical evoked potentials in amygdala-prefrontal circuits
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Cortico-cortical evoked potential (CCEP) amplitude will be quantified from local field potentials recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes following single-pulse intracranial electrical stimulation. CCEP amplitude will be used to assess effective connectivity between the amygdala and prefrontal cortex.
Theta/gamma band power in amygdala-prefrontal circuits
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Theta (4-8 Hz) and gamma (30-50 Hz) band power will be quantified from local field potentials recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes in the amygdala and prefrontal cortex. Theta/gamma-band power will be assessed during fear conditioning and extinction to characterize oscillatory neural activity within amygdala-prefrontal circuits.
Cross-frequency coupling in amygdala-prefrontal circuits
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Cross-frequency coupling will be quantified from local field potentials recorded through clinically implanted stereoelectroencephalography (SEEG) electrodes in the amygdala and prefrontal cortex. Coupling between neural activity across different frequency bands, including phase-amplitude coupling between lower-frequency oscillations and high-frequency activity, will be assessed during resting state and fear processing to characterize cross-frequency neural interactions within amygdala-prefrontal circuits.
Skin conductance response amplitude during fear conditioning and extinction
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Skin conductance response (SCR) amplitude will be quantified during fear conditioning and extinction to assess autonomic responses to conditioned stimuli.
Pupil diameter during fear conditioning and extinction
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Pupil diameter will be quantified from eye-tracking recordings during fear conditioning and extinction to assess autonomic responses to conditioned stimuli.
Button press reaction time during fear conditioning and extinction
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Button press reaction time will be quantified during fear conditioning and extinction to assess behavioral responses to conditioned stimuli.
Subjective unpleasantness rating during fear conditioning and extinction
时间窗: During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.
Participants will rate the unpleasantness of the conditioned stimuli during fear conditioning and extinction. Ratings will be used to quantify subjective emotional responses to the conditioned stimuli.
次要结局
- Heart rate during fear conditioning and extinction(During research sessions, up to 2 hours per day for up to 4 days during the participant's hospital stay.)