What is Tinnitus?
Tinnitus is an auditory perception that is not produced by an external sound. Tinnitus is not the same for everyone! People describe it as a hissing, roaring, chirping, buzzing, clanging or ringing sound. Tinnitus may range from high to low pitch, consist of multiple tones or sound like noise with no tonal quality at all. It may be constant, intermittent, or pulsed. It may begin suddenly or may come on gradually. Tinnitus is not a disease, but a symptom common to many problems, both physiological and psychological.
Approximately 50 million U.S. residents have experienced more than momentary tinnitus, with 2.5 million reporting feeling debilitated by it. As many as 10-12 million have sought help while 1 million new cases of tinnitus are identified per year.
Side effects of tinnitus may include sleep difficulties, fatigue, stress, trouble relaxing, difficulty concentrating, irritability and other mood disorders (Bauer and Bozoski, 2008). These side effects may impair one’s quality of life.
Tinnitus may be triggered or originate from within the auditory system or from related auditory structures. It may be a pointer to underlying pathological conditions or may be established on the basis of history. About half of sufferers do not have an identifiable onset point for their tinnitus (Bauer and Brozoski, 2008). It is therefore essential for a patient to receive a full medical evaluation for an extensive differential diagnosises. Underlying medical conditions must be identified and treated. Common causes include but are not limited to, acute acoustic trauma, Meniere’s disease attacks, chronic noise trauma, intoxications, acoustic neuromas, presbycusis (age-related hearing loss), and sudden deafness. Tinnitus may also be found in patients with normal hearing. Stouffer and Tyler (1990) found the primary diagnosis (35.8%) to be unknown.
Where is it coming from?
The neural generator for tinnitus was traditionally believed to reside in the cochlea (inner ear). Animal studies have found that following damage of the cochlear hair cells (cells that help us hear sound) due to noise exposure or ototoxic drugs that often induce tinnitus, there is no change and sometimes a reduction in spontaneous auditory nerve (hearing nerve) activity. Further, surgical sectioning of the auditory nerve fails to suppress tinnitus, and in >50% of the patients it made it worse. Also, surgical removal of the nerve often leads to the emergence of tinnitus in the ear that is surgically disconnected from the brain.
Sound evoked functional MRI studies have found activation in the Inferior Colliculi (Melcher, Levine, Bergevin, & Norris, 2009). Other studies have strongly suggested the limbic system and autonomic nervous system play a major role in the perception of tinnitus. The central auditory nervous system processes environmental sounds by identifying, sorting, and routing their associated neural signals. Sound can carry an emotional meaning and activate the limbic system, and/or cause behavioral reactions associated with the autonomic nervous system. Patients with tinnitus react the same way to external sounds as they do to their perceived tinnitus. Therefore, emotional responses increase the likelihood of paying attention to the tinnitus (Henry, Jastreboff, Jastreboff, Schechter, & Fausti, 2002). For example, if you are going to sleep one night and hear an unknown noise, your awareness and hearing sensitivity becomes heightened to listening for the sound again.
I have tinnitus, what can I do?
If there are no medical origins and tinnitus has become stressful, debilitating, and disruptive to your everyday activities, a therapy treatment may be beneficial. Our doctorate level audiologists trained in tinnitus treatment will provide a full audiological and tinnitus evaluation to determine the type of therapy that is most appropriate for you. Below is a list of common therapies.