Comparison of Heart Rate Variability Measurement on the Arm and Chest in Transcutaneous Auricular Vagus Nerve Stimulation

Heart rate variability is defined as the change in beat-to-beat interval, and the sympathetic and parasympathetic nervous system influences the change in beat-to-beat interval through cardiovascular connections. Heart rate variability measurement can be obtained by different methods. However, which method is more effective is controversial. The aim of this study was to investigate the differences between heart rate variability parameters measured on the chest, right arm and left arm.

Healthy participants aged 18-45 years will be included in the study. The inclusion criteria will be determined as being 18 years of age or older and not having any acute or chronic disease. Exclusion criteria will be determined as being previously involved in any neuromodulation intervention, smoking or alcohol use, and regular medication use.

Participants included in the study will be randomised into three groups and transcutaneous vagus nerve stimulation will be applied. The duration of treatment will be 20 minutes and single session stimulation will be performed. Current intensity, current passage time and frequency will be planned to be the same in each patient. Before and after stimulation, heart rate variability will be measured over the chest in the first group, over the right arm in the second group and over the left arm in the third group. Then, heart rate variability parameters (time-dependent, frequency-dependent) will be compared between the groups.