Most people who suffer from tinnitus also experience hearing loss to some degree. As they often accompany one another, the two conditions may be correlated. In fact, some researchers believe that subjective tinnitus can only occur if the auditory system has been previously damaged (source). The loss of certain sound frequencies due to hearing loss may change how the brain processes sound, causing it to adapt and fill in the gaps with tinnitus. The underlying hearing loss typically results from exposure to loud noises or advanced age:
Tinnitus can be caused by a variety of less common underlying conditions or injuries. If you have tinnitus, start your treatment path by seeking out a hearing healthcare professional who specializes in tinnitus diagnostics so they can help identify the underlying cause. If the common causes for tinnitus are ruled out, the practitioner will refer you to another specialist for further evaluation. Listed below are related medical specialties who might be able to help you determine the cause of your tinnitus. 
Spontaneous otoacoustic emissions (SOAEs), which are faint high-frequency tones that are produced in the inner ear and can be measured in the ear canal with a sensitive microphone, may also cause tinnitus.[6] About 8% of those with SOAEs and tinnitus have SOAE-linked tinnitus,[need quotation to verify] while the percentage of all cases of tinnitus caused by SOAEs is estimated at about 4%.[6]
TRT depends upon the natural ability of the brain to "habituate" a signal, to filter it out on a subconscious level so that it does not reach conscious perception. Habituation requires no conscious effort. People frequently habituate many auditory sounds -- air conditioners, computer fans, refrigerators, and gentle rain, among them. What they have in common is that they have no importance, so they are not perceived as ''loud.'' Thus, the brain can screen them out.
CBT involves working with a therapist or counselor, typically once per week, to identify and change negative thought patterns. CBT was initially developed as a treatment for depression and other psychological problems, but it seems to work well for people with tinnitus. Several studies and meta-reviews, including one published in the Korean Journal of Audiology, have found that CBT significantly improves irritation and annoyance that often comes with tinnitus.
A number of vital tasks carried out during sleep help maintain good health and enable people to function at their best. Sleep needs vary from individual to individual and change throughout your life. The National Institutes of Health recommend about 7-9 hours of sleep each night for older, school-aged children, teens, and most average adults; 10-12 for preschool-aged children; and 16-18 hours for newborns. There are two stages of sleep; 1) REM sleep (rapid-eye movement), and 2) NREM sleep (non-rapid-eye movement). The side effects of lack of sleep or insomnia include:
Loud noise exposure: Being exposed to occupational loud noise on a regular basis from heavy equipment, chain saws or firearms is a common cause of tinnitus. However, even if you don’t work in a noisy environment, you can still suffer the effects of noise exposure by listening to loud music through headphones, attending live music performances frequently and engaging in noisy hobbies.