Tinnitus, commonly described as whistles, clicks and hissing sounds is experienced by approximately 7 million Canadians. Fully half of which note that they are bothered by it, with nearly 1 million commenting that it is truly debilitating.
In the 1980’s Dr. Pawel Jastreboff, a world leader in tinnitus research, developed Tinnitus Retraining Therapy (TRT). It is based upon the neurophysiological model of tinnitus, which conceptualizes it as “a neural signal that can have varying effects on the central nervous system.”
Although not well known in the medical community or by those suffering with it, TRT has been soundly proven to greatly mitigate the effects of tinnitus, even for those who feel that it is having a catastrophic effect on their mental health and general well-being. TRT protocols include an audiological examination, educational counseling and sound therapy.
Approximately 80% of individuals who do experience tinnitus will need little in the way of intervention, but for the other 20%, successful TRT can be completed within a few weeks. Those with debilitating effects, however, may require up to a year of treatment to mitigate the effects. (A. Davis & Refaie, 2000; P. J. Jastreboff & Hazell, 2004)
The treatment plan that Murray Hearing Centre charts with the those affected by it begins with a full hearing test, which assesses for hearing loss and locates the tinnitus frequencies. The counseling aspect is designed to remove the negative associations which the people apply to their tinnitus, including fear and anger. At this point a ‘teacher/student’ relationship is formed which will lead them -in an unhurried and companionate manner- through a lesson-set in understanding the neurophysiological model and the benefits of sound therapy.
The latter is dispensed through very inconspicuous daytime worn (hearing aid style) sound generators. Nighttime, due to a lack of ambient sounds, can be torturous for as high quality restful sleep becomes an almost unattainable goal. Bedside masking devices will greatly aid in this.
The clinical goals of TRT are twofold: Habituation of the reactions to the tinnitus signal and secondly, habituation of its perception, or basically 'getting used to getting used to it, then ignoring it.' These objectives are accomplished through the neural mechanism of habituation, a natural learning process, whereby constant exposure to the generator’s innocuous sound stimulus acts to decrease the response to the tinnitus. This is a result of tinnitus being ‘reclassified’ to the status of a meaningless auditory signal within the subconscious; akin to the constant hiss of a computer fan.
The first and most important goal of TRT is habituation of the reactions to tinnitus, which predominantly involves the sympathetic part of the autonomic nervous system. It is this system that mediates the stress-related response and is controlled by the limbic system that mediates emotions.
Habituation of the perception of the tinnitus is the second goal, whereby tinnitus becomes an insignificant neural stimulus that will follow automatically once habituation of the reaction is achieved to a sufficient degree. When both goals are met, people will still be aware of the tinnitus, but only for small percentages of their waking hours and at best, it is only mildly bothersome.
Neural and Learning Principles of TRT
Tinnitus is a brain-centered neural signal that those suffering with it consciously perceives as sound which can lead to a negative emotional response. TRT reduces this response by training the brain to process it instead as an irrelevant auditory signal. In people who are bothered by it, this signal has been conditioned to trigger a negative reaction from stress-inducing thoughts, memories or experiences associated with the tinnitus. The key lays in the limbic and autonomic systems which are partly responsible for emotion.
Guidelines for Assessment and Treatment
The issue of referring tinnitus patients is largely a matter of professional perspective. There is no set consensus due to the diverse health care fields involved in managing tinnitus, including psychiatrists, ENT’s, family physicians, dentists and audiologists.
Numerous studies have recommended that the audiological field is to the
primary discipline for management, based upon its responsibility for hearing assessments, tinnitus surveys and sound therapy. If Meniere’s or an acoustic neuroma is suspected or sudden tinnitus experienced (with or with hearing loss) then an ENT referral is crucial.
By far the most common type is a subjective neural signal that is heard only by the patient. Objective tinnitus, also called somatosounds, may in some cases be heard by the examiner and can be triggered by TMJ, though most commonly it is of a pulsatile nature and is synchronous with the heartbeat. Objective tinnitus may be correctable with surgery and as such an ENT and/or dental referral is recommended.
Tinnitus patients are also disproportionately affected by depression and anxiety and if this is the case, it is essential that they receive proper care from a mental health provider. The Beck Depression Inventory is considered a standard assessment tool and can be completed in five minutes.
More so than any other tinnitus related problem is sleep disturbances
that again can be mitigated by bedside noise generators. Notwithstanding, all people reporting tinnitus should fill out the Tinnitus Handicap Inventory, that is completed at the hearing assessment.
There are five TRT/tinnitus categories:
‘0’ defines those with minimal problems and/or the onset of tinnitus is very recent. They may only require basic counseling, generally do not need sound generators and may not have hearing loss.
‘1’ defines those who require substantially more treatment than just basic counseling and are greatly affected in one area of their life, such as with sleep. Use of sound generators are generally beneficial.
‘2’ defines those who require an aggressive program and also report significant hearing loss which requires hearing aid/sound therapy hybrids.
‘3’ defines those with category ‘2’ affects and also experience recruitment, which is a decreased tolerance to moderately intense sounds; an average intensity telephone ring may be sufficient to illicit discomfort.
‘4’ is the most difficult to treat and is usually found in those within category ‘3’, who have subsequently had their tinnitus exacerbated from exposure to loud sounds and/or neurological problems induced the likes of head injury or stroke.
Of the millions of people affected by tinnitus, most will ignore it (most of the time) as they have habituated to it. Others, however, will focus upon it and react negatively, leading to a vicious upwards spiraling cycle of all the ills associated with tinnitus.
It is never the tinnitus which causes the problem, rather it is the reaction to it. If those suffering can learn to stop the negative reactions (or habituation of reaction), then over time the perception (or habituation of perception) will diminish and it will cease being a problem.
Although the neural mechanisms of tinnitus are not yet fully understood, by applying what is known about neural auditory processing, TRT has proven itself to be very successful at hundreds of clinics, world-wide, for 30 years.
What the patient has ‘learned’ about tinnitus can be ‘unlearned.’ By retraining the autonomic and limbic systems to deactivate the response to these signals, via the sensory cortex, it blocks them from reaching the cortical areas of awareness and instead is relegated to the depths of the subconscious.
Tinnitus is no longer something that one must ‘just learn to live with.’