Course of hearing loss and occurrence of tinnitus

PLoS ONE, 2012

Background: Different mechanisms have been proposed to be involved in tinnitus generation, among them reduced lateral inhibition and homeostatic plasticity. On a perceptual level these different mechanisms should be reflected by the relationship between the individual audiometric slope and the perceived tinnitus pitch. Whereas some studies found the tinnitus pitch corresponding to the maximum hearing loss, others stressed the relevance of the edge frequency. This study investigates the relationship between tinnitus pitch and audiometric slope in a large sample.

International Journal of Audiology, 2011

International journal of audiology, 2014

Objective: Psychoacoustic measures of tinnitus, in particular dominant tinnitus pitch and its relationship to the shape of the audiogram, are important in determining and verifying pathophysiological mechanisms of the condition. Our previous study postulated that this relationship might vary between different groups of people with tinnitus. For a small subset of participants with narrow tinnitus bandwidth, pitch was associated with the audiometric edge, consistent with the tonotopic reorganization theory. The current study objective was to establish this relationship in an independent sample. Design: This was a retrospective design using data from five studies conducted between 2008 and 2013. Study sample: From a cohort of 380 participants, a subgroup group of 129 with narrow tinnitus bandwidth were selected. Results: Tinnitus pitch generally fell within the area of hearing loss. There was a statistically significant correlation between dominant tinnitus pitch and edge frequency; hi...

European Archives of Oto-Rhino-Laryngology, 2014

Tinnitus is the phantom perception of sounds. No single theory explaining the cause of tinnitus enjoys universal acceptance, however, it is usually associated with hearing loss. The aim of this study was to investigate the relationship between tinnitus pitch and audiometry, minimum masking levels (MML), tinnitus loudness, and distortion product otoacoustic emissions (DPOAE). This was a retrospective analysis of participant's records from the University of Auckland Hearing and Tinnitus Clinic database. The sample consisted of 192 participants with chronic tinnitus (more than 18 months) who had comprehensive tinnitus assessment from March 2008 to January 2011. There were 116 males (mean = 56.5 years, SD = 12.96) and 76 females (mean = 58.7 years, SD = 13.88). Seventy-six percent of participants had a tinnitus pitch C8 kHz. Tinnitus pitch was most often matched to frequencies at which hearing threshold was 40-60 (T50) dBHL. There was a weak but statistically significant positive correlation between tinnitus pitch and T50 (r = 0.15 at p \ 0.05). No correlation was found between tinnitus pitch and DPOAEs, MML, audiometric edge and worst threshold. The strongest audiometric predictor for tinnitus pitch was the frequency at which threshold was approximately 50 dBHL. We postulate that this may be due to a change from primarily outer hair cell damage to lesions including inner hair cells at these levels of hearing loss.

Serbian Journal of Experimental and Clinical Research

Chronic tinnitus is often associated with hearing impairment, but it cannot be asserted that only hearing loss causes tinnitus. Audiograms of patients with tinnitus show that hearing loss occurred more often at high frequencies than at low frequencies. The aim of this study was to analyse the audiogram shapes of patients with chronic tinnitus and to identify the relationship between the shape of the audiogram and intensity and duration of tinnitus. This investigation was a cross case series study conducted at a general hospital in Kraljevo on patients with chronic subjective tinnitus. The study included 43 patients of both genders and of different ages. We used audiometry (measuring the threshold of hearing for frequencies from 250, 500, 1000, 2000, 4000 and 8000 Hz) and tympanometry. Each patient reported the intensity of tinnitus in each ear on a visual analogue scale (VAS1) and stated the duration of tinnitus for each ear. Our research showed that patients with chronic tinnitus h...

Hearing Research, 2006

A broad consensus within the neuroscience of tinnitus holds that this audiologic condition is triggered by central deafferentation, mostly due to cochlear damage. The absence of audiometrically detectable hearing loss however poses a challenge to this rather generalizing assumption. The aim of this study was therefore to scrutinize cochlear functioning in a sample of tinnitus subjects audiometrically matched to a normal hearing control group. Two tests were applied: the Threshold Equalizing Noise (TEN) test and a pitch scaling task. To perform well on both tasks relatively normal functioning of inner hair cells is a requirement. In the TEN test the tinnitus group revealed a circumscribed increment of thresholds partially overlapping with the tinnitus spectrum. Abnormal slopes were observed in the pitch scaling task which indicated that tinnitus subjects, when presented with a high-frequency stimulus, relied heavily on input derived from lower-frequency inner hair cells (off-frequency listening). In total both results argue for the presence of a deafferentation also in tinnitus subjects with audiometrically normal thresholds and therefore favour the deafferentation assumption posed by most neuroscientific theories.

International Archives of Otorhinolaryngology, 2015

Introduction Tinnitus is one of the symptoms that affects individuals suffering from noise induced hearing loss. This condition can be disabling, leading the affected individual to turn away from work. Objective This literature review aims to analyze the possible association between gender and tinnitus pitch and loudness, the degree of hearing loss and the frequencies affected in subjects with noise-induced hearing loss. Methods This contemporary cohort study was conducted through a cross-sectional analysis. The study sample consisted of adults with unilateral or bilateral tinnitus, who had been diagnosed with noise-induced hearing loss. The patients under analysis underwent an otorhinolaryngological evaluation, pure tone audiometry, and acuphenometry. Results The study included 33 subjects with noise-induced hearing loss diagnoses, of which 22 (66.7%) were men. Authors observed no statistical difference between gender and loudness/pitch tinnitus and loudness/pitch in subjects with bilateral tinnitus. Authors found an inverse relation between tinnitus loudness with intensity greater hearing threshold and the average of the thresholds and the grade of hearing loss. The tinnitus pitch showed no association with higher frequency of hearing threshold. Conclusion Data analysis shows that, among the individuals evaluated, the greater the hearing loss, the lower the loudness of tinnitus. We did not observe an association between hearing loss and tinnitus pitch.

International Archives of Otorhinolaryngology, 2016

Frontiers in Neurology, 2017

Frontiers in Aging Neuroscience