Tinnitus Retraining Therapy was developed in the late 1980’s by Pawel Jastreboff, Ph.D., Sc.D. first began developing his theory of the Neurophysiologic Model of Tinnitus and Tinnitus Retraining Therapy (TRT) in the late 1980’s while working at Yale University. The first publication of the Neurophysiological Model of Tinnitus can be found in 1990 in the journal Neuroscience Research, with his colleague Dr. Jonathan Hazel and Tinnitus Retraining Therapy (TRT) first published in the British Journal of Audiology (1993). Brenda Berge, Doctor of Audiology has been treating patients since completing her graduate school education, but returned to take additional training personally with the Drs. Jastreboff in 2009 for TRT and an Advanced Certification training in 2012.
The Neurophysiological Model of Tinnitus reveals the physiological and psychological foundations that affect this abnormal neurological feedback loop, akin to ‘Phantom Limb’ of the ear:
Fundamentally, the symptom occurs due to a loss of sensory cells (outer hair cells of the cochlea) resulting in this symptom, being akin to ‘phantom limb’ syndrome of the ear. The processing of information occurs on several levels beginning from the lack of stimulation from the ear up to the auditory nervous system (due to lack of outer hair cell functioning or reduced outer hair cell functioning), through the sub-cortical regions of the brain (which are akin to the ‘autopilot’ portion of the brain that without conscious awareness keeps our heart pumping blood, keeps our respiratory system running, etc) which is where the ‘error message’ occurs, until it reaches the patient’s conscious level of Perception (awareness), then causes them to Evaluate the symptom (then the emotional reaction to that evaluation, and not being able to find the source of the sound) is the abnormal neurological feedback loop that occurs, and can become distressing for some patients.
- The auditory system is closely connected with the part of the brain that controls emotions (limbic system) and the automatic response of the body to danger (autonomic nervous system).
- Connections within the nervous system are continuously modified, resulting in the enhancement of significant signals and a decrease of neuronal response to irrelevant signals.
- Sounds that occur in the absence of the patient being able to assess or attribute originating from a sound source that they can evaluate (as being threatening or not) results in a subconscious reaction of the body’s self protective reflex of a “fight or flight” response. The persistence of this sound(s) results in enhancement of its perception and a resistance of the perception to be suppressed by other signals. The repetition of this signal of an unattributable source becomes associated with negative reinforcement, causing the patient emotional frustration, upset or in rare cases distress (per Hoffman, 2004).
This processing of information results in continuous changes of the connections within the brain that are involved in transmitting signals from the ear to the cortex. Repeated activations by a sound not associated with anything of significance will result in decreased activation of the cortical and limbic areas. However, hounds that occur that the human cannot attribute and cognitively identified with a particular sound source get processed as a signal alerting ‘danger’ to the subcortical centres in the brain, which then activate the emotional response and autonomic nervous system which disrupts other aspects of a patient’s quality of life. Sounds associated to ‘danger’ (those which cannot be evaluated, will be enhanced and will strongly activate the cortical areas and emotional response. Our brain sorts sounds according to their significance, giving important sounds high priority and filtering out, or habituating, insignificant sounds. The rules controlling sorting priorities are in flux and change throughout an individual’s lifetime. TRT postulates that with the proper training one can enhance their perception of some sounds while training their brain to filter out other sounds.
This is the basis of TRT, training the brain to habituate tinnitus sounds and classifying them to represent a neutral, insignificant signal. To achieve this it is necessary to fulfill two basic conditions:
- Removal of the negative association attached to tinnitus perception.
- Preservation of tinnitus detection, but not constant evaluation with the elimination of the emotional ‘reaction’ is necessary for treatment.
Signals that induce fear or indicate danger cannot and should not be habituated. We must not habituate sounds that provide warning signals. The decreased negative association of tinnitus is achieved through directive counseling. The patient is taught the basic function of the auditory system and the brain relative to tinnitus that decreases the reaction of the autonomic nervous system.
The second condition is less obvious but equally important. In order to retrain the neuronal networks, it is imperative that tinnitus be detected. Retraining cannot be achieved for a signal that is masked or undetectable. Thus, for habituation oriented therapy, masking of tinnitus is counterproductive. Low level, broad band sound is used to facilitate tinnitus habituation.
Silence actually enhances tinnitus, therefore patients undergoing TRT are advised to avoid silence. They should immerse themselves in a low level, emotionally neutral sound environment.
Dr. Jastreboff’s website and contact information can be found at http://www.tinnitus-pjj.com/.
Brenda Berge, Doctor of Audiology has been treating patients with tinnitus since graduating with her Au.D., but undertook to train directly with Drs. P & M. Jastreboff in 2009, and their Advanced Training certificate in 2012. She does comprehensive tinnitus evaluations to help find the source and co-morbid conditions and exacerbating factors of the patient’s tinnitus to develop a treatment plan that is specified to each patient based upon their full medical file. She is specifically interested in the Collaborative Care Model for patients who experience their tinnitus secondary to concussion or Post Concussion Syndrome onset, to explore and assist patients in finding treatment that is most efficacious, based upon emerging medical information, as it becomes available in the clinical literature.