The acronym for 'autonomous sensory meridian response'. Basically low-grade euphoria that is experienced as a tingling sensation that begins at the scalp and moves down the spine. A genre of videos intended to induce ASMR has emerged, over 15 million of which had been published on YouTube by 2021, most of which serve to help listeners fall asleep. ASMR videos often use a binaural microphone for the best results.