Inserting a small object into the ear canal to clean it is a common practice despite being discouraged by medical professionals. This activity triggers a unique physiological response that registers in the brain as intensely pleasurable or relieving. The satisfaction comes from stimulating nerve endings that are linked to distant parts of the body, creating an unexpected sensory experience that the brain quickly learns to crave.
Sensory Nerves Behind the Pleasure
The skin lining the ear canal is highly innervated with sensory nerve fibers. This area is one of the few places where branches of major cranial nerves are close enough to the surface to be easily stimulated. The primary player in the unique sensation is the auricular branch of the Vagus nerve, often referred to as Arnold’s nerve. This nerve connects the ear canal directly to the nervous system’s control center for various internal organs. Stimulating this nerve can result in Arnold’s nerve reflex, which may trigger a mild cough or a tickle sensation in the throat for some people. The Glossopharyngeal nerve also contributes fibers to the ear canal, adding to this widespread, intense feeling.
How the Brain Processes the Stimulus
The intense physical sensation created by stimulating the ear canal is processed in the brain’s reward circuitry. When the sensory nerves are activated, the brain interprets the stimulation as a form of relief, similar to scratching a persistent itch. This relief triggers the release of neurotransmitters, most notably dopamine, within the mesolimbic pathway, the brain’s central reward system. Dopamine reinforces the behavior that caused the pleasurable feeling. The nucleus accumbens is flooded with dopamine, which tells the brain to repeat the action, creating a positive reinforcement loop and turning the act of cleaning into a satisfying habit.
Why Cleaning Ears Can Be Dangerous
Inserting objects into the ear canal, such as cotton swabs, is discouraged by medical professionals due to the risk of injury. The ear is a self-cleaning organ, and cerumen, or earwax, naturally migrates out of the canal due to the movement of the jaw. Earwax is a protective substance that contains lubricating, antibacterial, and antifungal properties. Using an object to clean the ear often pushes the cerumen deeper into the canal, which can cause impaction against the eardrum. This blockage can result in pain, fullness, and temporary hearing loss. Inserting a cotton swab can cause micro-lacerations in the thin skin, increasing the risk of painful outer ear infections. Pushing too far can perforate the tympanic membrane (eardrum), causing severe pain, drainage, and conductive hearing loss.