Étude sur l'hypersensibilité auditive
The Tinnitus and Hyperacusis Research Laboratory is nested within the International Laboratory for Brain, Music, and Sound Research located at Université de Montréal, Montréal, Canada, which is jointly affiliated to Université de Montréal and McGill University. We conduct fundamental and clinical research and develop instruments to better characterize normal hearing as well as hearing pathologies.
Our research focuses on two hearing problems increasingly recognized as major public health issues, namely tinnitus and hyperacusis, and their co-morbidities.
Tinnitus – defined as a sound perceived in the ears or head in the absence of an external sound source – presents with variable pitch (humming, whistling) and loudness (soft or loud) qualities. Tinnitus affects approximately 10 to 12 % of the general population, with prevalence rates increasing up to about 30% after age 50  and even higher among workers with occupational hearing loss. Our laboratory develops psychoacoustical methods to better characterize tinnitus, in order to improve its diagnosis and study how the tinnitus percept is modified by intervention.
Although tinnitus is well tolerated by most of the affected people, 1 to 2 % experience severe distress. Why this is so is poorly understood. The notion that non-auditory factors play a critical role in tinnitus-related distress is a central theme of our research program, emphasizing theaffective (distress) dimensions of tinnitus. Accordingly, our research also focuses on tinnitus co-morbidities such as stress [2-3] and sleep problems [4, 5], and how they can either modulate or be modulated, by the presence of tinnitus- a typical (and intriguing) chicken and egg conundrum.
Hyperacusis is defined as abnormally excessive intolerance to common sounds in the environment, in spite of normal or near-normal hearing. For instance, a hyperacusis sufferer cannot tolerate certain sounds perceived as normal by others, nor tolerate noisy environments. In other words, the person becomes hypersensitive to, and behaviourally ill affected by environmental sounds. Remarkably, there is no consensus concerning the prevalence of hyperacusis, partly because of a lack of objective criteria and variable definition from one study to another.
Tinnitus and hyperacusis can be viewed as pathologies of loudness perception, which is the attribute of an auditory percept that can be ordered on a scale from quiet to loud. We are interested in exploring how normal loudness is encoded in the brain and how it can be modulated in normal hearing listeners. In order to better understand the mechanisms of normal loudness, tinnitus and hyperacusis, and to plan intervention studies, our laboratory recruits highly qualified people from a wide range of disciplines: we recruit and welcome graduate students with an Audiology, Neuroscience, Psychology, Music, Engineering, and Life Sciences background.
- Shargorodsky, J., G.C. Curhan, and W.R. Farwell, Prevalence and characteristics of tinnitus among US adults. Am J Med, 2010. 123(8): p. 711-8.
- Simoens, V.L. and S. Hébert, Cortisol suppression and hearing thresholds in tinnitus after low-dose dexamethasone challenge.BMC Ear Nose Throat Disord, 2012. 12: p. 4.
- Hébert, S., B. Canlon, and D. Hasson, Emotional Exhaustion as a Predictor of Tinnitus. Psychother Psychosom, 2012. 81(5): p. 324-326.
- Hébert, S., S. Fullum, and J. Carrier, Polysomnographic and quantitative electroencephalographic correlates of subjective sleep complaints in chronic tinnitus. J Sleep Res, 2011. 20(1 Pt 1): p. 38-44.
- Hébert, S. and J. Carrier, Sleep Complaints in Elderly Tinnitus Patients: A Controlled Study. Ear Hear, 2007. 28(5): p. 649-655.