Tinnitus is a symptom, not a disease. Most cases are due to damage to the microscopic endings of the sensory nerve in the inner ear, commonly from exposure to loud noise (as from amplified music or gunfire). Other causes include allergy, high or low blood pressure, a tumor, diabetes, thyroid dysfunction, and head or neck injury. In addition, some drugs, including aspirin and other anti-inflammatories, antibiotics, sedatives, and antidepressants can also cause tinnitus. If so, changing drugs or lowering the dosage usually helps.
There are many different conditions and disorders that affect nerve channels leading to the ears, which can cause someone to hear abnormal ringing or other sounds in their ears. These conditions usually cause other symptoms at the same time (such as dizziness, hearing loss, headaches, facial paralysis, nausea and loss of balance), which doctors use as clues to uncover the underlying cause of tinnitus.
Muscular tinnitus can be caused by several degenerative diseases that affect the head and neck including amyotrophic lateral sclerosis or multiple sclerosis. Myoclonus can also cause muscular tinnitus, especially palatal myoclonus, which is characterized by abnormal contractions of the muscles of the roof of the mouth. Spasms of the stapedial muscle (which attaches to the stapes bone or stirrup), which is the smallest muscle in the body, and tensor tympani muscle, both of which are located in the middle ear, have also been associated with objective tinnitus. Myoclonus or muscle spasms may be caused by an underlying disorder such as a tumor, tissue death caused by lack of oxygen (infarction), or degenerative disease, but it is most commonly a benign and self-limiting problem.
CBT could potentially help people with tinnitus deal with fears that their tinnitus might be caused by brain damage or might lead to deafness. During CBT, they might learn that the condition is common and that it is not associated with brain damage or deafness. They might also be exposed to the sound in a safe environment, so that it has less of an impact on their daily life. CBT also involves techniques such as applied relaxation and mindfulness training.
When there does not seem to be a connection with a disorder of the inner ear or auditory nerve, the tinnitus is called nonotic (i.e. not otic). In some 30% of tinnitus cases, the tinnitus is influenced by the somatosensory system, for instance people can increase or decrease their tinnitus by moving their face, head, or neck. This type is called somatic or craniocervical tinnitus, since it is only head or neck movements that have an effect.