Depression Disorder, fMRI Research, Heart-Brain Coupling
Conditions
Keywords
Functional Connectivity, Individualized treatment, Transcranial magnetic stimulation
Brief summary
This study focuses on individuals with depressive tendencies and investigates the regulatory effects of Transcranial Magnetic Stimulation (TMS)-guided by personalized functional connectivity mapping-on heart-brain coupling in this population, while also exploring the underlying mechanisms.Participants will undergo 3T functional magnetic resonance imaging (fMRI) scans, followed by four different types of neurostimulation: stimulation targeting individualized Dorsolateral Prefrontal Cortex (DLPFC) -Subgenual Anterior Cingulate Cortex (sgACC) functional connectivity, stimulation targeting individualized DLPFC-insula functional connectivity, standard F3 targeting, and sham stimulation. The order of these stimulation sessions will be randomized. Researchers will simultaneously record the participants' electroencephalogram (EEG) and electrocardiography (ECG) signals before and after stimulation, and will record ECG in real-time during the stimulation. The primary objective of this study is to investigate the effects of DLPFC targeting specificity on metrics such as heart-brain coupling in individuals with depressive tendencies, thereby providing a basis for future research on objective assessment and personalized interventions for depression.
Detailed description
This is an exploratory, randomized, single-blind, sham-controlled, within-subject crossover study designed to investigate the regulatory effects-and underlying mechanisms-of TMS (based on individualized functional connectivity targeting) on heart-brain coupling in individuals with depressive tendencies. Participants will undergo structural and functional neuroimaging using a 3T MRI scanner. The imaging protocol includes a structural T1-weighted scan and a functional blood-oxygen-level-dependent (BOLD) scan, used for structural image registration and functional connectivity analysis to identify TMS stimulation targets. In this study targeting individuals with depressive tendencies, each participant will undergo four distinct stimulation conditions: individualized DLPFC-sgACC functional connectivity targeting, individualized DLPFC-insula functional connectivity targeting, standard F3 targeting, and sham stimulation. The order of these four conditions will be balanced using a Latin square design to minimize sequence effects, learning effects, and carry-over effects between conditions; a minimum interval of 5 days will be maintained between experimental sessions. High-frequency Repetitive transcranial magnetic stimulation (rTMS) will be used for the intervention, with the following parameters: stimulation frequency of 10 Hz, intensity at 90% of resting motor threshold (RMT), 2-second stimulation duration, 8-second inter-train interval, 20 pulses per train, and 45 repetitions (totaling 900 pulses), resulting in a total session duration of approximately 7.5 minutes. Primary measures include: Phase-Amplitude Coupling (PAC), which reflects real-time information exchange between the central and autonomic nervous systems and serves as a key biomarker for the functional status of the "brain-heart axis"; TMS-induced Heart-Brain Coupling (HBC), which quantifies the rhythmic effects of TMS and provides direct evidence regarding the engagement of the prefrontal-vagal pathway; Heartbeat-Evoked Potentials (HEP), an EEG component extracted via time-locking to the ECG R-peak, which precisely reflects cortical processing of cardiac afferent signals and interoceptive function; and Heart Rate Variability (HRV), which reflects the balance of sympathetic and parasympathetic regulation. Secondary measures include EEG power spectra, fMRI data, heart rate (HR), and clinical assessment scales.
Interventions
DEVICEDLPFC-insula TMS
Transcranial magnetic stimulation was applied to the dorsolateral prefrontal cortex (DLPFC); the specific insular subregion exerting the greatest negative influence on the left DLPFC was identified based on Granger causality connectivity. Stimulation parameters were as follows: frequency of 10 Hz, intensity of 90% of the resting motor threshold (RMT), a 2-second stimulation duration followed by an 8-second inter-stimulus interval, and 45 repeated sequences (each comprising 20 pulses) for a total of 900 pulses, resulting in a total session duration of approximately 7.5 minutes.
DEVICEDLPFC-sgACC TMS
Transcranial magnetic stimulation was applied to the dorsolateral prefrontal cortex, with individualized targeting of the region in the left dorsolateral prefrontal cortex showing the strongest negative functional correlation with the subgenual anterior cingulate cortex. The stimulation parameters were: frequency of 10 Hz, intensity of 90% of the resting motor threshold (RMT), 2-second stimulation duration, and 8-second inter-stimulus interval; each sequence comprised 20 pulses, with 45 sequences repeated for a total of 900 pulses, resulting in a total session duration of approximately 7.5 minutes.
DEVICE10-20 F3 TMS
Transcranial magnetic stimulation was applied to the dorsolateral prefrontal cortex, targeting the F3 site based on the international 10-20 system. The stimulation parameters were as follows: frequency of 10 Hz, intensity of 90% RMT, 2-second stimulation duration, 8-second inter-train interval, and 20 pulses per train; a total of 45 trains were delivered (900 pulses in total), with a single session lasting approximately 7.5 minutes.
DEVICEsham TMS
A form of sham transcranial magnetic stimulation-either inactive or sensory-matched-designed to simulate the sensation of stimulation associated with device activation without delivering therapeutic frequencies.
Sponsors
Xidian University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
一、Inclusion criteria for the depressed group: 1. Aged 18-30 years; 2. Recent feelings of low mood and presence of depressive symptoms; 3. Physically healthy, with no history of neurological disorders; 4. No participation in other neuromodulation experiments within the past month; 5. Normal hearing and normal (or corrected-to-normal) vision; 6. PHQ-9 score \> 5 and BDI-II score \> 13; 7. Avoidance of staying up late, alcohol consumption, and excessive caffeine intake prior to the experiment; 8. Able and willing to cooperate with the completion of scale assessments. 二、Inclusion criteria for healthy participants: (1) Aged 18-30 years; (2) No significant symptoms of depression and no history of neuropsychiatric disorders; (3) Physically healthy with no history of neurological disorders; (4) No participation in other neuromodulation experiments within the past month; (5) Normal hearing and normal (or corrected-to-normal) vision; (6) PHQ-9 score \< 5 and BDI-II score \< 13; (7) Avoidance of staying up late, alcohol consumption, and excessive caffeine intake prior to the experiment; (8) Able and willing to cooperate with the completion of scale assessments.
Exclusion criteria
1. History of head trauma (including neurosurgery), stroke, elevated intracranial pressure, or other brain-related disorders; 2. History of epileptic seizures or family history of epilepsy; 3. Receipt of TMS or other neuromodulation stimulation within the past month; 4. Presence of intracranial or internal metallic foreign bodies, electrodes made of silver or gold, or metal prostheses; 5. Presence of devices potentially affected by TMS, such as pacemakers, drug pumps, cochlear implants, or implanted brain stimulators; 6. Severe or recent cardiac, pulmonary, or hematopoietic system disorders, or other neurological diseases; 7. Clinically diagnosed moderate-to-severe depressive disorder; 8. Substance abuse, alcohol dependence, etc.; 9. Current active suicidal ideation or suicidal behavior; Refusal to sign the informed consent form.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| TMS-induced heart-brain coupling | Perioperative. During the 7-minute-22-second treatment period under each stimulation condition. | By linking the stimulation rhythm to the inter-beat interval and quantifying the rhythmic effects of TMS, direct evidence is provided regarding the engagement of the prefrontal-vagal pathway. |
| Phase-amplitude coupling | Perioperative period. Specifically, within 10 minutes before and after each stimulus condition. | It reflects the real-time exchange of information between the central nervous system and the autonomic nervous system, serving as an important biomarker of the functional status of the "brain-heart axis." |
| Heartbeat-evoked potentials | Perioperative period. Specifically, within 10 minutes before and after each stimulus condition. | An EEG component extracted via time-locking to the cardiac R-peak. It precisely reflects the cerebral cortex's processing of cardiac afferent signals and interoceptive function. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| EEG power spectrum | Perioperative period. Specifically, within 10 minutes before and after each stimulus condition. | It describes the distribution of power (energy) of EEG signals as a function of frequency. By transforming complex time-domain EEG signals into the frequency domain, it reveals energy distribution across different frequency bands, thereby helping to identify changes in the brain's functional state under various conditions. |
| Functional connectivity of brain networks | Baseline. During the 6-minute-30-second fMRI scan. | The analysis of functional connectivity in brain networks aims to reveal the mechanisms of coordinated activity among brain regions and dynamic individual differences, thereby providing an objective scientific basis for the diagnosis, elucidation of pathological mechanisms, and precision treatment of neuropsychiatric disorders. |
| Transient Assessment Scale | Baseline and Perioperative. | Patient Health Questionnaire -9 items, with a total score range of 0-27 points. The higher the score, the more severe the depressive symptoms may be. The Beck Depression Inventory (BDI-II) has a total score range of 0-63, with higher scores indicating more severe depressive symptoms. The State Trait Anxiety Inventory (STAI) is a psychological assessment tool used to measure anxiety, divided into two subscales: state anxiety and trait anxiety. The total score of each subscale ranges from 20 to 80 points, with higher scores indicating higher levels of anxiety. The Pittsburgh Sleep Quality Index (PSQI) is used to evaluate sleep quality in clinical and basic research, with a total score ranging from 0 to 21 on the PSQI scale. The higher the score, the worse the sleep quality. |
Countries
China
Contacts
CONTACTXue-Juan, Yang
Outcome results
None listed