@togetherunprocessed: The sternum overlies the thymus gland and the anterior vagal trunk, with chest wall mechanoreceptors transmitting vibration signals through the thoracic spinal cord to brainstem vagal nuclei. Rhythmic tapping produces low-frequency vibration that stimulates these pathways similarly to the mechanism underlying therapeutic chest percussion used in respiratory physiotherapy. Research on tapping-based interventions including EFT demonstrates measurable cortisol reduction and heart rate variability improvement following sustained rhythmic stimulation of chest wall points.