Tinnitus to the inner ear can cause tinnitus, other apparent causes (e.g., temporomandibular joint dysfunction) are difficult to explain. It may be caused by increased neural activity in the auditory brainstem, where the brain processes sounds, causing some auditory nerve cells to become over-excited. The basis of this theory is that many with tinnitus also have hearing loss. Three reviews of 2016 emphasized the large range and possible combinations of pathologies involved in tinnitus, which in turn result in a great variety of symptoms demanding specifically adapted therapies. Even when tinnitus is the primary complaint, audiological evaluation is usually preceded by
Body dysmorphic disorder estimated to affect up to 2.4% of the population. It usually starts during adolescence and affects both men and women. The BDD subtype muscle dysmorphia, perceiving the body as too small, affects mostly males. Besides thinking about it, one repetitively checks and compares the perceived flaw, and can adopt unusual routines to avoid social contact that exposes it. Fearing the stigma of vanity, one usually hides the preoccupation. Commonly unsuspected even by psychiatrists, BDD has been underdiagnosed. Severely impairing quality of life via educational and occupational dysfunction and social isolation, BDD has high rates of suicidal thoughts and suicide attempts.