Two ears are better than one The human brain requires information from both ears in order to accurately perceive the sounds of our environment. Because the human auditory system is designed to pick up sounds from both ears, many people find that they hear better with two hearing aids than they do with only one. Therefore, when a hearing loss is identified in both ears a bilateral hearing aid fitting is recommended. A bilateral hearing aid fitting is when a hearing aid is worn in both ears. The primary benefits to a bilateral hearing aid fitting include improved sound localization, and improved listening in noise.