Cardiac Autonomic and Anxiety Regulation Via Closed-loop nEurofeedback in Recurrent Pregnancy Loss

Summary

The goal of this clinical trial is to learn whether right dorsolateral prefrontal cortex (right DLPFC)-targeted fNIRS-BCI online closed-loop neurofeedback, delivered with slow-wave acoustic cueing, can reduce anxiety symptoms and improve cardiac autonomic regulation in women with recurrent pregnancy loss (RPL) and comorbid anxiety (women aged 18-45 years, right-handed, currently not pregnant or in a missed miscarriage state).

The main questions it aims to answer are:

Does real neurofeedback increase the proportion of participants who achieve an anxiety treatment response (defined as ≥50% reduction in Hamilton Anxiety Rating Scale \[HAMA\] total score from baseline) compared with sham feedback, at end of treatment and at 3-month follow-up? Is the intervention safe and well tolerated, as reflected by between-group differences in adverse events during the training period? Do brain and autonomic measures show between-group differences during the first formal session, including right DLPFC HbO downregulation, interhemispheric DLPFC synchronisation, heart rate (HR), and heart rate variability (HRV) indices? Researchers will compare real right DLPFC neurofeedback to sham feedback (identical procedures and displays but weakened coupling to real-time neural activity) to see if real neurofeedback improves anxiety outcomes and brain-heart autonomic regulation.

Participants will:

Complete screening, baseline clinical assessments, and physical examination Be randomly assigned (1:1) to real neurofeedback or sham feedback Complete 3 days of adaptation training followed by 3 weeks of training (15 sessions; one weekday session per day; \~20 minutes each) using a block design with slow-wave acoustic cueing (1 Hz amplitude-modulated tone; 20 s rest + 40 s cueing per block; 20 blocks/session) Undergo fNIRS recording in all sessions, with ECG recorded in session 1 only (for HR/HRV analyses) Receive matched, guideline-informed cognitive-behavioural therapy (CBT) during the intervention period Complete anxiety-related assessments at baseline, \~1 hour after the final session, and 3 months after treatment, with adverse events monitored throughout the intervention period

Conditions

• Recurrent Pregnancy Loss
• Anxiety

Interventions

DEVICE

Right DLPFC fNIRS-BCI closed-loop neurofeedback (real feedback)

This device-based intervention delivers fNIRS-BCI online closed-loop neurofeedback targeting the right dorsolateral prefrontal cortex (right DLPFC) with slow-wave acoustic cueing. Participants complete a 3-day adaptation phase followed by 3 weeks of formal training (15 weekday visits; about 20 minutes per visit). Each visit includes 20 blocks (60 seconds per block: 20 seconds rest + 40 seconds slow-wave acoustic cueing with a \~60 dB, 1 Hz sinusoidally amplitude-modulated pure tone). During each cueing period, real-time right DLPFC HbO activity estimated from fNIRS is displayed as a visual activation bar, and participants apply volitional strategies to downregulate activity below a concealed threshold line (T = -3.3; approximating p = 0.001). fNIRS is recorded in all visits; ECG is recorded on the first formal training day only for HR/HRV mechanistic measures.

DEVICE

Right DLPFC fNIRS-BCI neurofeedback (sham feedback)

This device-based sham intervention uses the same fNIRS-BCI neurofeedback interface, slow-wave acoustic cueing, and training schedule as the real-feedback arm. Participants complete a 3-day adaptation phase followed by 3 weeks of formal training (15 weekday visits; about 20 minutes per visit) using 20 blocks per visit (60 seconds per block: 20 seconds rest + 40 seconds slow-wave acoustic cueing with a \~60 dB, 1 Hz sinusoidally amplitude-modulated pure tone). fNIRS is recorded in all visits; ECG is recorded on the first formal training day only for HR/HRV measures. The displayed activation bar and concealed threshold line are configured to substantially weaken effective coupling to the participant's instantaneous neural activity (threshold setting: T = -1; approximating p = 0.31), making reliable volitional control unlikely while preserving blinding.

Sponsors & Collaborators

• Shenyang Medical College

  lead OTHER

Principal Investigators

• Lin Tao, MM · Shenyang Medical College

• Yun-En Liu, MD · Shenyang Medical College

• Fei Meng, MD · Central Hospital Affiliated to Shenyang Medical Collage

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-12-29

Primary Completion

2026-10-30

Completion

2026-10-30

Countries

• China

Study Locations