The relationship between tinnitus pitch and parameters of audiometry and distortion product otoacoustic emissions

Comparisons of Audiologic Characteristics in Patients with Continuous and Intermittent Tinnitus

BACKGROUND

No studies to date have compared audiologic characteristics in patients with continuous and intermittent tinnitus. The present study classified tinnitus patients into continuous and intermittent groups based on tinnitus duration and compared their audiologic characteristics.

METHODS

This study enrolled 604 patients with tinnitus from January 2019 to December 2022. Clinical manifestations, PTA results, the frequency and loudness of tinnitus, ABR, DPOAE, and TEOAE tests were compared in patients with continuous and intermittent tinnitus.

RESULTS

Of the 604 patients, 231 (38.2%) had continuous and 373 (61.8%) had intermittent tinnitus. There were no significant between-group differences in otologic symptoms, tinnitus onomatopoeia. PTA showed that hearing thresholds, except at 125 Hz, were significantly higher in patients with continuous rather than intermittent tinnitus. The loudness of tinnitus was significantly greater in patients with continuous rather than intermittent tinnitus. ABR tests showed that the absolute latency of wave V was significantly longer in continuous than in intermittent tinnitus. Signal-to-noise ratios on TEOAE tests were significantly lower in patients with continuous rather than intermittent tinnitus at all frequencies tested (1, 1.5, 2, 3, and 4 kHz). Response rates to sound stimuli at all frequencies, except for 1 kHz, were significantly lower on DPOAE tests in patients with continuous rather than intermittent tinnitus.

CONCLUSIONS

Continuous tinnitus is more common in males, more persistent over time, and is associated with a higher rate of hearing loss. In contrast, intermittent tinnitus is more common in women, appears acutely, and is associated with a relatively lower rate of hearing loss. Based on the findings of the current paper, it seems that audiologic characteristics may differ between patients with continuous and intermittent tinnitus.

Predictive coding and stochastic resonance as fundamental principles of auditory phantom perception

Mechanistic insight is achieved only when experiments are employed to test formal or computational models. Furthermore, in analogy to lesion studies, phantom perception may serve as a vehicle to understand the fundamental processing principles underlying healthy auditory perception. With a special focus on tinnitus-as the prime example of auditory phantom perception-we review recent work at the intersection of artificial intelligence, psychology and neuroscience. In particular, we discuss why everyone with tinnitus suffers from (at least hidden) hearing loss, but not everyone with hearing loss suffers from tinnitus. We argue that intrinsic neural noise is generated and amplified along the auditory pathway as a compensatory mechanism to restore normal hearing based on adaptive stochastic resonance. The neural noise increase can then be misinterpreted as auditory input and perceived as tinnitus. This mechanism can be formalized in the Bayesian brain framework, where the percept (posterior) assimilates a prior prediction (brain's expectations) and likelihood (bottom-up neural signal). A higher mean and lower variance (i.e. enhanced precision) of the likelihood shifts the posterior, evincing a misinterpretation of sensory evidence, which may be further confounded by plastic changes in the brain that underwrite prior predictions. Hence, two fundamental processing principles provide the most explanatory power for the emergence of auditory phantom perceptions: predictive coding as a top-down and adaptive stochastic resonance as a complementary bottom-up mechanism. We conclude that both principles also play a crucial role in healthy auditory perception. Finally, in the context of neuroscience-inspired artificial intelligence, both processing principles may serve to improve contemporary machine learning techniques.

Does the tinnitus pitch correlate with the frequency of hearing loss?

BACKGROUND

The tonotopic model of tinnitus claims that the tinnitus pitch corresponds to the audiometric edge; the homeostatic model suggests that it falls within the hearing loss (HL) area. The existing evidence mostly supports the homeostatic model, but the relationship between the tinnitus pitch and the HL frequencies has been insufficiently explored.

AIMS/OBJECTIVE

To investigate the association between the tinnitus pitch and the audiometric profile in the largest study population to date.

MATERIALS AND METHODS

Three hundred and ninety-three patients with tonal or narrow-band tinnitus participated. HL frequencies included 30, 40, 50 (F50), 60 dB, and maximum HL. We defined edge frequencies in four different ways according to the existing studies. We assessed the association between all estimated frequencies and the tinnitus pitch using t-tests, Spearman's correlation, and multiple regression.

RESULTS

All calculated frequencies differed significantly from the tinnitus pitch except for F50. None were correlated with the tinnitus pitch. F50 was the only significant predictor among the estimated frequencies in multiple regression.

CONCLUSIONS

The tinnitus pitch fell within the HL area, and was mildly associated with F50.

SIGNIFICANCE

Our results support the homeostatic tinnitus model, and provide reliable evidence that tinnitus pitch does not correspond to the audiometric edge.

The ototoxic potential of cobalt from metal-on-metal hip implants: a pilot study on the patient-reported auditory, vestibular, and general neurological outcome

OBJECTIVE

This study aimed to systematically investigate the ototoxic potential of cobalt in patients with a metal-on-metal (MoM) hip implant, using objective auditory and vestibular assessments and a questionnaire. The results of the objective evaluation were published previously, whereas the current study focused on the questionnaire outcome and its relationship to the blood cobalt level. Design and study sample: Twenty patients (33-65 years) with a primary MoM hip implant and 20 non-implanted control subjects, matched for age, gender, and noise exposure, received a questionnaire to evaluate the presence of several hearing and balance symptoms (part 1) and general neurological issues (part 2).

RESULTS

Concerning part 1, the proportion of auditory-related symptoms in general (p = 0.022) and tinnitus (p = 0.047) was significantly higher in the MoM patient group, whereas no group difference was found for hyperacusis, increased listening effort, and decreased speech understanding. Concerning part 2, no significant group differences were detected. Within the MoM patient group, the questionnaire outcome was not significantly different between the low-exposure and high-exposure subgroups according to the blood Co level.

CONCLUSIONS

In line with our previous study, these results potentially imply Co-induced impairment to the auditory system, despite the lack of a clear dose-response relationship.

Cortical Tonotopic Map Changes in Humans Are Larger in Hearing Loss Than in Additional Tinnitus

Neural plasticity due to hearing loss results in tonotopic map changes. Several studies have suggested a relation between hearing loss-induced tonotopic reorganization and tinnitus. This large fMRI study on humans was intended to clarify the relations between hearing loss, tinnitus, and tonotopic reorganization. To determine the differential effect of hearing loss and tinnitus, both male and female participants with bilateral high-frequency hearing loss, with and without tinnitus, and a control group were included. In a total of 90 participants, bilateral cortical responses to sound stimulation were measured with loudness-matched pure-tone stimuli (0.25-8 kHz). In the bilateral auditory cortices, the high-frequency sound-evoked activation level was higher in both hearing-impaired participant groups, compared with the control group. This was most prominent in the hearing loss group without tinnitus. Similarly, the tonotopic maps for the hearing loss without tinnitus group were significantly different from the controls, whereas the maps of those with tinnitus were not. These results show that higher response amplitudes and map reorganization are a characteristic of hearing loss, not of tinnitus. Both tonotopic maps and response amplitudes of tinnitus participants appear intermediate to the controls and hearing loss without tinnitus group. This observation suggests a connection between tinnitus and an incomplete form of central compensation to hearing loss, rather than excessive adaptation. One implication of this may be that treatments for tinnitus shift their focus toward enhancing the cortical plasticity, instead of reversing it.SIGNIFICANCE STATEMENT Tinnitus, a common and potentially devastating condition, is the presence of a "phantom" sound that often accompanies hearing loss. Hearing loss is known to induce plastic changes in cortical and subcortical areas. Although plasticity is a valuable trait that allows the human brain to rewire and recover from injury and sensory deprivation, it can lead to tinnitus as an unwanted side effect. In this large fMRI study, we provide evidence that tinnitus is related to a more conservative form of reorganization than in hearing loss without tinnitus. This result contrasts with the previous notion that tinnitus is related to excessive reorganization. As a consequence, treatments for tinnitus may need to enhance the cortical plasticity, rather than reverse it.

Test-Retest Reproducibility of Response Duration in Tinnitus Patients With Positive Residual Inhibition

Purpose Functional imaging is often used to try to elucidate the pathophysiological mechanism of tinnitus. Residual inhibition, the temporary suppression of tinnitus after application of a masking noise, could be an interesting technique to modulate tinnitus perception in functional imaging paradigms. The purposes of this study were to primarily assess reproducibility of the (partial) positive residual inhibition response duration in patients with tinnitus and to explore its utility in experimental designs. Method Patients with tinnitus exhibiting a (partial) positive residual inhibition response or tinnitus reduction after a 1-min white noise presentation were selected from a broad consulting tinnitus population. In 27 patients, this response was tested 4 times: twice during initial testing and twice during a retest of the psychoacoustic tinnitus measures, 4-8 weeks after initial consultation. In 17 patients with stable residual inhibition responses, reproducibility of response duration, the duration of tinnitus reduction up to pretesting state, was analyzed. Results Initial testing showed a residual inhibition duration of 29.5 s on average. Test-retest reproducibility of response duration was shown to be reliable with an ICC(3, 4) of .871 (95% CI [0.733, 0.948]) and a standard error of measurement of 6.64 s. Conclusions This study indicates the good test-retest reproducibility of residual inhibition duration in our subset of 17 patients with stable (partial) positive residual inhibition. Residual inhibition is, therefore, a technique that can potentially be used for temporary tinnitus manipulation in experimental paradigms to unravel tinnitus pathophysiology.

Speech Comprehension and Its Relation to Other Auditory Parameters in Elderly Patients With Tinnitus

Deteriorated speech comprehension is a common manifestation of the age-related decline of auditory functions (presbycusis). It could be assumed that when presbycusis is accompanied by tinnitus, general hearing functions, and particularly comprehension of speech in quiet and speech in noise (SIN), will be significantly affected. In this study, speech comprehension ability and other parameters of auditory function were assessed in elderly subjects with (T, n = 25) and without (NT, n = 26) tinnitus, aiming for examination of both peripheral and central auditory processing. Apart from high-frequency audiograms in quiet and in background noise, speech recognition thresholds in silence or in competitive babble noise, and the ability to understand temporally gated speech (GS), we measured also sensitivity to frequency modulation (FM) and interaural delay, gap detection thresholds (GDT), or the difference limens of intensity. The results show that in elderly participants matched by age (mean ages around 68 years), cognitive status (median MoCA scores around 27), and hearing thresholds [median pure-tone averages (PTA) around 16 dB hearing loss (HL)], tinnitus per se has little influence on speech comprehension. The tinnitus patients also show similar GDT, sensitivity to interaural intensity difference, and sensitivity to FM as the NT subjects. Despite these similarities, nevertheless, significant differences in auditory processing have been found in the tinnitus participants: a worse ability to detect tones in noise, a higher sensitivity to intensity changes, and a higher sensitivity to interaural time differences. Additional correlation analyses further revealed that speech comprehension in the T subjects is dependent on the sensitivity to temporal modulation and interaural time delay (ITD), while these correlations are weak and non-significant in the NT subjects. Therefore, despite similarities in average speech comprehension and several other parameters of auditory function, elderly people with tinnitus exhibit different auditory processing, particularly at a suprathreshold level. The results also suggest that speech comprehension ability of elderly tinnitus patients relies more on temporal features of the sound stimuli, especially under difficult conditions, compared to elderly people without tinnitus.

Is there auditory impairment in Parkinson's disease?

ABSTRACT Objective: to describe the audiological profile of a group of patients with Parkinson's disease and to investigate the association between hearing loss and the disease. Methods: 50 individuals with and 46 without Parkinson's disease underwent Pure Tone Audiometry, Otoacoustic Emissions by Distortion Product, and auditory processing tests. The results of the patients were compared to those obtained in individuals without the disease, according to clinical and biological variables. Results: in individuals with Parkinson's disease, 82% presented hearing loss, 53.5% alterations in Otoacoustic Emissions by Distortion Product, 78%, alterations in temporal processing, and 12%, changes in binaural integration. Individuals with the disease had a greater impairment in the recognition of duration patterns when compared to those without the disease, with a worse performance in men and in individuals aged between 42 and 65 years old and Hoehn and Yahr I and II stages. Conclusions: the profile found corresponds to descending sensorineural hearing loss and alteration in otoacoustic emissions, temporal ordering and noise gaps detection.Only losses in temporal order are associated with the disease, especially in men, individuals under the age of 65 and in the initial stage.

The Association of Reactive Oxygen Species Levels on Noise Induced Hearing Loss of High Risk Workers in Dr. Soetomo General Hospital Surabaya, Indonesia

Excessive noise exposure could increase the production of reactive oxygen species in the cochlea, thus causing the risk of noise-induced hearing loss (NIHL). Noise is commonly found in the industrial sites. However, public places like hospital also can have noisy location which risk the workers of NIHL. To analyzed the correlation of reactive oxygen species and hearing impairment to employees at risk in the hospital. Participants were obtained by identifying the employees in hospital from 3813. They were examined for baseline characteristics, hearing loss and reactive oxygen species. Hearing loss was defined as audiometry and tympanometry level. The statistical test that used in this study is Chi square test (p < 0.05). The proportion of participant was 42.43 ± 10.72 years old in women (58.33%) and noise levels at Dr. Soetomo General Hospital was 98.15 ± 8.16 dB in range 85.39-112.90 dB. The prevalence of NIHL was 47.92% (audiometry) and 70.83% (otoacoustic emission). Reactive oxygen species estimated 5.55 ± 4.39 ng/ml. Statistical analysis of reactive oxygen species to audiometry (p = 0.993) and reactive oxygen species to otoacoustic emission (p = 0.647). Increased production of reactive oxygen species that cause hearing loss, but there was no correlation between reactive oxygen species and hearing loss in risk worker at the hospital.