with earplugs in last night, and the sound of my heart beat woke me up this morning, why would i be able to hear my heart beating because i have earplugs in any one know?
Essentially, the rebounding resonance of the systolic mitral valve is the same ocisloscopic pattern of the frequential modulation of the reboundation echo of the BBC station to which you were tuned.
Seriously though, the carotid artery, quite a large artery, is routed almost over the inner ear. When wearing sound restricting devices, eliminating outside sound, one hears the pulsing of the blood through this artery.