Asked by: Alison Shields, Buckinghamshire
Often when we are tired, our eyes feel itchy and rubbing them stimulates the tear ducts to release lubricating fluid. But there is also a weird connection between the ophthalmic nerve that serves the face, scalp and eyes, and the vagus nerve that runs to the heart. Rubbing your face or pressing your eyes triggers the ‘oculocardiac reflex’, which lowers the heart rate. This can help you relax when you are tired or stressed.
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