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.
Aged 18-30 years;
Recent feelings of low mood and presence of depressive symptoms;
Physically healthy, with no history of neurological disorders;
No participation in other neuromodulation experiments within the past month;
History of head trauma (including neurosurgery), stroke, elevated intracranial pressure, or other brain-related disorders;
History of epileptic seizures or family history of epilepsy;
Receipt of TMS or other neuromodulation stimulation within the past month;
Presence of intracranial or internal metallic foreign bodies, electrodes made of silver or gold, or metal prostheses;
Crossover
DLPFC-insula TMS
DeviceTranscranial 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.
DLPFC-sgACC TMS
DeviceTranscranial 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.
10-20 F3 TMS
DeviceTranscranial 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.
sham TMS
DeviceA 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.
TMS-induced heart-brain coupling
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
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
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.
EEG power spectrum
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
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
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.
Click on the lead sponsor to view all of their trials.
