Frequency-Dependent Effects of Auricular Vagus Nerve Stimulation on Autonomic and Cardiovascular Parameters

Condition(s) studied

Investigational drug(s) / intervention(s)

Pulsetto FIT™ - Sham tcVNS: The Pulsetto FIT™ device is placed bilaterally on the cervical region (posterior margin of the sternocleidomastoid muscle). In the sham condition, the device displays normal operational lights but delivers no electrical stimulation (0 Hz; inactive mode). This condition is used for blinding and as the control comparator. Dose: 10 minutes

Pulsetto FIT™ - tcVNS 10 Hz: Bilateral transcutaneous cervical vagus nerve stimulation delivered via the Pulsetto FIT™ device at 10 Hz, 250 µs pulse width. Current intensity adjusted to a mild, non-painful tingling sensation, individualized for each participant. Dose: 10 minutes

Pulsetto FIT™ - tcVNS 25 Hz: Bilateral tcVNS using the Pulsetto FIT™ device at 25 Hz, 250 µs pulse width. Stimulation intensity set at a comfortable sensory level. Dose: 10 minutes

Pulsetto FIT™ - tcVNS 50 Hz: Bilateral cervical vagus nerve stimulation via Pulsetto FIT™ at 50 Hz, 250 µs pulse width. Intensity adjusted to a tolerable sensory level without discomfort. Dose: 10 minutes

Pulsetto FIT™ - tcVNS 100 Hz: Bilateral tcVNS delivered with the Pulsetto FIT™ device at 100 Hz, 250 µs pulse width. Highest stimulation frequency used in this protocol; current intensity individualized per participant comfort. Dose: 10 minutes

Study summary

This randomized, sham-controlled, crossover study investigates the acute autonomic effects of transcutaneous cervical vagus nerve stimulation (tcVNS) applied at five different frequencies (0 Hz/sham, 10 Hz, 25 Hz, 50 Hz, 100 Hz) in healthy adults. The primary objective is to determine how stimulation frequency modulates heart rate variability (HRV), blood pressure, and respiratory rate. The study aims to establish a frequency-specific dose-response model using validated physiological measurements.

Eligibility

Primary outcome measure(s)

• Heart Rate Variability (HRV) Changes (ΔRMSSD, ΔHF, ΔLF/HF) — Pre- vs Post-stimulation (5-min segments)(5-minute baseline, 5-minute stimulation, 5-minute post period)
  HRV is recorded using a validated high-resolution heart rate monitor (Polar H10) during a 5-minute resting baseline (T0) and a 5-minute post-stimulation period (T2). The following time- and frequency-domain parameters are analyzed: RMSSD, HF (ms²), and LF/HF ratio. Artefact correction is performed using standard HRV processing methods. Acute autonomic response is quantified by calculating change scores (Δ = post-pre) for each stimulation frequency.

Trial sites (1)

More SEFA HAKTAN HATIK trials in Turkey

Other trials for the same condition