The labyrinth holds the organs of balance and hearing. It’s made up of 2 parts: Bony labyrinth Membranous labyrinth The membranous labyrinth is encased in bone and contains a fluid called endolymph. When the head moves, the endolymph also moves. This causes nerve receptors in the membranous labyrinth to signal the brain about the body's motion. Too much endolymph buildup in the labyrinth can interfere with the normal balance and hearing signals between the inner ear and the brain. This is Ménière disease. Fluid buildup in this area may be caused by: Allergies Abnormal immune system response Abnormal fluid drainage caused by a blockage Head injury Genetics Migraine headaches Viral infection