Tinnitus remains a symptom that affects the lives of millions of people. Research is directed not only at its treatment, but also at understanding why it occurs. Research by doctors at the University at Buffalo, The State University of New York, Dalhousie University (Canada), and Southeast China University have published research using electrophysiology and functional MRI to better understand what parts of the brain are involved in hearing and the production of tinnitus. Their research has found that much larger areas of the brain are involved with the process of hearing than previously believed, which may help direct future diagnostic and therapeutic options.
Tinnitus usually comes in the form of a high-pitched tone in one or both ears, but can also sound like a clicking, roaring or whooshing sound. While tinnitus isn't fully understood, it is known to be a sign that something is wrong in the auditory system: the ear, the auditory nerve that connects the inner ear to the brain, or the parts of the brain that process sound. Something as simple as a piece of earwax blocking the ear canal can cause tinnitus, but it can also arise from a number of health conditions. For example, when sensory cells in the inner ear are damaged from loud noise, the resulting hearing loss changes some of the signals in the brain to cause tinnitus.
We occasionally recommend neuropsychological testing using a simple screening questionnaire -- depression, anxiety, and OCD (obsessive compulsive disorder) are common in persons with tinnitus. This is not surprising considering how disturbing tinnitus may be to ones life (Holmes and Padgham, 2009). Persons with OCD tend to "obsess" about tinnitus. Treatment of these psychological conditions may be extremely helpful.
Supporting the idea that central reorganization is overestimated as "the" cause of tinnitus, a recent study by Wineland et al showed no changes in central connectivity of auditory cortex or other key cortical regions (Wineland et al, 2012). Considering other parts of the brain, Ueyama et al (2013) reported that there was increased fMRI activity in the bilateral rectus gyri, as well as cingulate gyri correlating with distress. Loudness was correlated with values in the thalamus, bilateral hippocampus and left caudate. In other words, the changes in the brain associated with tinnitus seem to be associated with emotional reaction (e.g. cingulate), and input systems (e.g. thalamus). There are a few areas whose role is not so obvious (e.g. caudate). This makes a more sense than the Wineland result, but of course, they were measuring different things. MRI studies related to audition or dizziness must be interpreted with great caution as the magnetic field of the MRI stimulates the inner ear, and because MRI scanners are noisy.
Michael Chrostowski, PhD is the founder of Sound Options Tinnitus Treatments Inc. His dedication to improving the lives of tinnitus sufferers drives his vision of providing effective, affordable and accessible treatments for the many tinnitus sufferers he has met throughout his research career. With over 8 years of research in the field of tinnitus and collaborations with leaders in the field, Dr. Chrostowski was able to make use of cutting-edge research to develop software that can customize an effective and personal treatment for tinnitus. Dr. Chrostowski received a BASc in electrical and computer engineering at the University of Toronto and a PhD in neuroscience at McMaster University.
Tinnitus habituation therapies, such as tinnitus retraining therapy (TRT), involve using low level sounds in a graduated fashion to decrease the perception of tinnitus. This differs from use of masking devices such as described earlier. TRT involves a wearable device that an affected individual can adjust so that the level of sound emitting from the device is about equal to or matches the tinnitus sound. This may be called the “mixing point” because the sound from the device and the tinnitus sound begin to mix together. An affected individual must repeatedly adjust the device so that the sound is at or just below the mixing point. TRT is supported by counseling with a trained professional who can teach the individual the proper techniques to maximize the effectiveness of TRT. Eventually, by following this method, affected individuals no longer need the external sound generating device. Affected individuals will become accustomed to the tinnitus sound (habituation), except when they choose to focus on it. Even then the sound will not be bothersome or troubling. The theory is akin to a person’s ability to ignore sounds such as the hum of air conditioner, the refrigerator motor turning on, or raindrops falling on the roof when driving a car in the rain.
Between 2007 and 2011, the researchers recruited 492 Dutch adults who had been diagnosed with tinnitus. The patients had to fulfil several criteria, including having no underlying disease that was causing their tinnitus, no other health issues that precluded their participation, and to have received no treatment for their tinnitus in the five previous years. Some 66% of adults originally screened for the study participated after screening.
Ringing-in-the-ears or a fullness-of-the-head sensation are the most common symptoms of tinnitus. While ringing is the most common experience, the noise can also sound like a buzzing, hissing or whizzing sound. It can range from a low pitch to a high pitch and may be soft or loud at times. For some, tinnitus seems to get louder at night, just before sleep when no other sounds are competing with it. Tinnitus can remain constant or come and go intermittently. In severe cases, the ringing in the ears is loud enough to interfere with work or daily activity, whereas those with mild tinnitus can experience soft ringing that is no more than a minor annoyance.