What effect do ear infections have on hearing?
When sounds, which are vibrations in the air, enter the ear canal, they in turn make the eardrum and ossicles vibrate. The ciliated cells in the cochlea transform the vibrations into nerve pulses, which transmit the message through the auditory nerve to the brain.
When there is an infection in the ear, liquid accumulates behind the eardrum. This liquid, which can be very thin or thick like honey, blocks the transmission of sound waves.
A child with an ear infection might have trouble distinguishing certain word sounds or hearing speech, especially when there’s ambient noise. Ear infections can also cause a language delay in young children. For school-age children, the problems that can be seen in class are decreased listening attention, difficulty understanding instructions, difficulty grasping the sound a letter makes when learning to read and write, and/or difficulty participating in activities requiring communication.
Some studies have shown that, in the long term, sensory privation caused by liquid behind the eardrum can lead to immature central auditory pathways and potentially to auditory synaptopathy (bad connection between neurons in the central auditory system).
If your child appears to have trouble hearing or seems to have pain in the ear, they need to see a doctor (family doctor or ENT) and have their hearing tested.
BY MÉLANIE BRIÈRE, Audiologist, Polyclinique de l’Oreille