ASMR, at its core, is a sensory experience characterized by a pleasant tingling sensation that typically begins in the scalp and moves down the back of the neck and upper spine. It's a response to certain triggers, often auditory or visual, and it can evoke a feeling of deep relaxation and even euphoria in some individuals. Think of it as a kind of brain massage, triggered by sounds like whispers, tapping, or the rustling of paper.