The big drivers of hearing loss are pretty well-known. There’s getting older, which is the biggest one. Too much noise all at once (standing too close to fireworks going off, for example) and over a long period of time (a noisy work environment) are next in line.

But there are also some obscure paths that lead to hearing loss.

Let’s start with Benign Paroxysmal Positional Vertigo (BPPV) because it’s so easy to pronounce. The shortcut designation is ear rocks (otoconia to be methodological). This is a buildup of calcium carbonate crystals in the ear. It can be treated in a number of ways, from drug therapy to surgery to exercises meant to get the crystal formations to basically dislodge themselves from the inner ear.

Similarly, otosclerosis is a hardening of the tiny bones in the inner ear. Generally a hereditary trait, treatment options vary but rarely can prevent the loss of at least some hearing.

A still-mysterious condition is autoimmune inner ear disease (AIED), which is when — for reasons not understood — the body’s immune system decides to take on parts of the inner ear. Tinnitus, problems with balance, and hearing loss can result. Treatment is usually based on steroid therapy and blood filtration.

Labyrinthitis is an infection of the nerve system within the ear. There is swelling that interferes with signals being transmitted to the brain. Common symptoms include vertigo and nausea. It’s a serious condition. Quick treatment with antiviral or antibacterial therapies can stave off long-term complications.

Another syndrome that can cause vertigo is Ménière’s disease, which can also bring on tinnitus, ear-popping, and hearing degradation. Like AIED, what triggers it is still not well understood. A range of issues — fluid accumulation, infection, head trauma, genetic predisposition — play a role and treatment options vary widely from patient to patient.

Finally, acoustic neuroma — luckily an unusual disorder — is a benign tumor that breaks down the functioning of the inner ear, especially its communication with the brain. It usually means surgery.