[Functional neuroimaging options for tinnitus]. / Möglichkeiten der funktionellen Bildgebung bei Tinnitus.

BACKGROUND: The pathophysiology behind tinnitus is still not well understood. Different imaging methods help in the understanding of the complex relationships that lead to the perception of tinnitus. OBJECTIVE: Herein, different functional imaging methods that can be used in the study of tinnitus are presented. MATERIALS AND METHODS: Considering the recent literature on the subject, the relevant imaging methods used in tinnitus research are discussed. RESULTS AND CONCLUSION: Functional imaging can reveal correlates of tinnitus. Due to the still limited temporal and spatial resolution of current imaging modalities, a conclusive explanation of tinnitus remains elusive. With increasing use of functional imaging, additional important insights into the explanation of tinnitus will be gained in the future.

[German-language versions of the Tinnitus Functional Index : Comparison of the two validated German-language versions of the Tinnitus Functional Index for Switzerland and Germany]. / Deutschsprachige Versionen des Tinnitus Functional Index : Vergleich der beiden validierten deutschsprachigen Versionen des Tinnitus Functional Index für die Schweiz und für Deutschland.

BACKGROUND: Two validated German-language versions of the Tinnitus Functional Index (TFI) exist, one for Switzerland and one for Germany. The TFI is considered to be a possible new standard questionnaire for evaluation of tinnitus severity and tinnitus treatment. OBJECTIVE: Considering the standardization taking place in tinnitus evaluation, our aim was to compare the two German-language TFI versions and to recommend only one TFI version in the German-speaking area. MATERIALS AND METHODS: The two German-language TFI versions were compared in a multicenter and randomized online questionnaire study with a crossover design. RESULTS: The total score of the two TFI versions did not differ in the total population. However, when further divided in terms of population and order of presentation of the TFI versions, there were significant differences in some cases, albeit with only moderate effect sizes. This suggests that the two versions are slightly different but still comparable. In factor analysis for the TFI version for Germany, in the entire population as well as in the Swiss population, six factors could be extracted. In contrast, for the German and Swiss TFI versions, only five factors could be extracted in the German population, and for the Swiss TFI version, only five factors in the Swiss population. CONCLUSION: The two German-language versions of the TFI are well comparable with each other. However, the factor analysis rather argues for use of the TFI version for Germany in the entire German-speaking region.

[The professional ear user-implications for the prevention, diagnosis, and treatment of ear diseases]. / Der "Professional Ear User" ­ Implikationen für die Prävention, Diagnostik und Therapie von Ohrerkrankungen.

BACKGROUND: Perfect hearing is crucial to the practice of various professions, such as instrument makers, musicians, sound engineers, and other professions not related to music, such as sonar technicians. For people of these occupational groups, we propose the term "professional ear user" (PEU) in analogy to "professional voice user". PEUs have special requirements for their hearing health, as they have well-known above-average auditory perceptual abilities on which they are professionally dependent. OBJECTIVE: The purpose of this narrative review is to summarize selected aspects of the prevention, diagnosis, and treatment of ear disorders in PEUs. RESULTS AND CONCLUSION: Prevention of hearing disorders and other ear diseases includes protection from excessive sound levels, avoidance of ototoxins and nicotine, and a safe manner of cleaning the outer auditory canal. Diagnosing hearing disorders in PEUs can be challenging, since subclinical but relevant changes in hearing cannot be reliably objectified by conventional audiometric methods. Moreover, the fact that a PEU is affected by an ear disease may influence treatment decisions. Further, physicians must be vigilant for non-organic ear diseases in PEUs. Lastly, measures to promote comprehensive ear health in PEUs as part of an educational program and to maintain ear health by means of a specialized otolaryngology service are discussed. In contrast to existing concepts, we lay the attention on the entirety of occupational groups that are specifically dependent on their ear health in a professional setting. In this context, we suggest avoiding a sole focus on hearing disorders and their prevention, but rather encourage the maintenance of a comprehensive ear health.

Accounting for Heterogeneity: Mixed-Effects Models in Resting-State EEG Data in a Sample of Tinnitus Sufferers.

In neuroscience, neural oscillations and other features of brain activity recorded by electroencephalography (EEG) are typically statistically assessed on the basis of the study's population mean to identify possible blueprints for healthy subjects, or subjects with diagnosable neurological or psychiatric disorders. Despite some inter-individual similarities, there is reason to believe that a discernible portion of the individual brain activity is subject-specific. In order to encompass the potential individual source of variance in EEG data and psychometric parameters, we introduce an innovative application of linear mixed-effects models (LMM) as an alternative procedure for the analysis of resting-state EEG data. Using LMM, individual differences can be modelled through the assumptions of idiosyncrasy of all responses and dependency among data points (e.g., from the same subject within and across units of time) via random effects parameters. This report provides an example of how LMM can be used for the statistical analysis of resting-state EEG data in a heterogeneous group of subjects; namely, people who suffer from tinnitus (ringing in the ear/s). Results from 49 participants (38 male, mean age of 46.69 ± 12.65 years) revealed that EEG signals were not only associated with specific recording sites, but exhibited regional specific oscillations in conjunction to symptom severity. Tinnitus distress targeted the frequency bands beta3 (23.5-35 Hz) and gamma (35.5-45 Hz) in right frontal regions, whereas delta (0.5-4 Hz) exhibited significant changes in temporal-parietal sources. Further, 57.8% of the total variance in EEG power was subject-specific and acknowledged by the LMM framework and its prediction. Thus, a deeper understanding of both the underlying statistical and physiological patterns of EEG data was gained.

Investigating the Efficacy of an Individualized Alpha/Delta Neurofeedback Protocol in the Treatment of Chronic Tinnitus.

First attempts have demonstrated that the application of alpha/delta neurofeedback in the treatment of chronic tinnitus leads to a reduction of symptoms at the group level. However, recent research also suggests that chronic tinnitus is a decidedly heterogeneous phenomenon, one that requires treatment of distinct subgroups or even on an individual level. Thus, the purpose of this study was to evaluate an individually adjusted alpha/delta neurofeedback protocol. Following previous studies, the delta band fixed between 3 and 4 Hz was chosen as the frequency for inhibition. However, unlike the previous studies, the frequency range for the rewarded alpha band was not fixed between 8 and 12 Hz but rather individually determined according to each patient's specific alpha peak frequency (IAF). Twenty-six chronic tinnitus patients participated in 15 weekly neurofeedback training sessions and extensive pre- and post-tests, as well as follow-up testing 3 and 6 months after training. The main outcome measures were tinnitus-related distress measured with the Tinnitus Handicap Inventory (THI) and Tinnitus Questionnaire (TQ), tinnitus loudness, and pre- and post-training resting-state EEG activity in trained frequency bands. In Results, the neurofeedback protocol led to a significant reduction of tinnitus-related distress and tinnitus loudness. While distress remained on a low level even 6 months after the completion of training, loudness returned to baseline levels in the follow-up period. In addition, resting-state EEG activity showed an increase in the trained alpha/delta ratio over the course of the training. This ratio increase was related to training-induced changes of tinnitus-related distress as measured with TQ, mainly due to increases in the alpha frequency range. In sum, this study confirms the alpha/delta neurofeedback as a suitable option for the treatment of chronic tinnitus and represents a first step towards the development of individual neurofeedback protocols. This clinical trial was registered online at ClinicalTrials.gov (NCT02383147) and kofam.ch (SNCTP000001313).

Tinnitus functional index: validation of the German version for Switzerland.

BACKGROUND: Different standardized questionnaires are used to assess tinnitus severity, making comparisons across studies difficult. These questionnaires are also used to measure treatment-related changes in tinnitus although they were not designed for this purpose. To solve these problems, a new questionnaire - the Tinnitus Functional Index (TFI) - has been established. The TFI is highly responsive to treatment-related change and promises to be the new gold standard in tinnitus evaluation. The aim of the current study was to validate a German version of the TFI for a German-speaking population in Switzerland. METHODS: At the ENT department of the University Hospital Zurich, 264 subjects completed an online survey including the German version for Switzerland of TFI, Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and sociodemographic variables. Internal consistency of the TFI was calculated with Cronbach's alpha coefficient. Pearson correlation coefficients were used for the test-retest reliability of the TFI and to investigate convergent and discriminant validity between the THI and the BDI and BAI, respectively. Factor analysis was assessed using a principal component analysis with oblique rotation. The different factors extracted were then compared with the original questionnaire. RESULTS: The German version of the TFI for Switzerland showed an excellent internal consistency (Cronbach's alpha of 0.97) and an excellent test-retest reliability of 0.91. The convergent validity with THI was high (r = 0.86). The discriminant validity with BAI and BDI showed moderate results (BAI: r = 0.60 and BDI: r = 0.65). In the factor analysis only five factors with one main factor could be extracted instead of eight factors as described in the original version. Nevertheless, relations to the original eight subscales could be demonstrated. CONCLUSION: The German version of the TFI for Switzerland is a suitable instrument for measuring the impact of tinnitus. The reliability and validity of this version are comparable with the original version of the TFI. Although this study showed only five factors in the factor analysis, relations to the original eight subscales were identified. Therefore, the German version of the TFI for Switzerland can deliver relevant information regarding the different tinnitus domains. TRIAL REGISTRATION: Clinical trial registration number on clinicaltrial.gov: NCT01837368 .

[Validation of the German Version of Tinnitus Functional Index (TFI)]. / Validierung der deutschen Version des Tinnitus Functional Index (TFI).

Tinnitus belongs to seriously debilitating auditory conditions and is often complicated by comorbidities such as insomnia, difficulties with concentration, depression, frustration and irritability. To facilitate the grading of symptoms and the effects of therapeutic strategies, we validated a German-version Tinnitus Functional Index (TFI) in 229 subjects suffering from chronic tinnitus. Outcome validity was assessed using the Tinnitus Questionnaire (TQ, German adaptation by Goebel u. Hiller [1998]). Construct validity was assessed using the "Hamburger Allgemeine Depressionsskala" (HADS). The German TFI featured excellent internal consistency (total score Cronbach's α=0.93). Factor analysis disclosed eight TFI subscales as proposed earlier by Meikle et al. [2012]. Intercorrelations were strong both between the TFI and the TQ (r=0.83), and between the TFI and the HADS (depression r=0.49, anxiety r=0.51). The German-version TFI qualifies as a rapid and statistically robust tool for grading the impact of tinnitus on daily living and for the measurements of therapeutic effects. Regarding depressive symptomatology, sensitivity of the TFI was comparable to that of the TQ.

Validation of PRISM (Pictorial Representation of Illness and Self Measure) as a novel visual assessment tool for the burden of suffering in tinnitus patients.

BACKGROUND: Chronic subjective tinnitus is a frequent condition that affects the subject's quality of life. The lack of objective measures of tinnitus necessitates the use of self-reporting and often time-consuming questionnaires for evaluating tinnitus severity. The Pictorial Representation of Illness and Self Measure (PRISM) is a two dimensional pictorial method to assess the burden of suffering. Patients illustrate their burden of suffering by the distance from a "self" to an illness circle, whereby a shorter distance indicates a higher burden of suffering. The aim of this prospective observational study was to validate the burden of suffering measured with PRISM in tinnitus patients by comparing it with different standardized questionnaires currently used in tinnitus evaluation. METHODS: A total of 188 patients filled out an online-based survey including sociodemographic variables and the following questionnaires: Tinnitus Handicap Inventory (THI), Tinnitus Questionnaire (TQ), WHO Quality of Life-Questionnaire (WHOQOL-BREF), and the Beck Depression Inventory (BDI). The subtle differences in the burden of suffering were accessed by using PRISM as an iPad version. Based on PRISM performance patients could easily be assigned in three groups, these being mildly, moderately, or severely affected akin to the standard questionnaires. RESULTS: The burden of suffering measured with PRISM correlated with the tinnitus severity (THI and TQ), depressive symptoms (BDI), and health related quality of life (WHOQOL-BREF) (all p ≤ 0.001). In the three PRISM groups tinnitus severity (THI and TQ), and depressive symptoms (BDI) differed significantly (all p ≤ 0.01). CONCLUSION: PRISM is an easily understood and time saving method for the assessment of burden of suffering in tinnitus patients. In daily clinical practice PRISM can help to identify patients with decompensated tinnitus that require more intensive treatment.

Changes in motor cortex excitability associated with temporal repetitive transcranial magnetic stimulation in tinnitus: hints for cross-modal plasticity?

BACKGROUND: Motor cortex excitability was found to be changed after repetitive transcranial magnetic stimulation (rTMS) of the temporal cortex highlighting the occurrence of cross-modal plasticity in non-invasive brain stimulation. Here, we investigated the effects of temporal low-frequency rTMS on motor cortex plasticity in a large sample of tinnitus patients. In 116 patients with chronic tinnitus different parameters of cortical excitability were assessed before and after ten rTMS treatment sessions. Patients received one of three different protocols all including 1 Hz rTMS over the left temporal cortex. Treatment response was defined as improvement by at least five points in the tinnitus questionnaire (TQ). Variables of interest were resting motor threshold (RMT), short-interval intra-cortical inhibition (SICI), intracortical facilitation (ICF), and cortical silent period (CSP). RESULTS: After rTMS treatment RMT was decreased by about 1% of stimulator output near-significantly in the whole group of patients. SICI was associated with significant changes with respect to treatment response. The group of treatment responders showed a decrease of SICI over the course of treatment, the group of non-responders the reverse pattern. CONCLUSIONS: Minor RMT changes during rTMS treatment do not necessarily suggest the need for systematic re-examination of the RMT for safety and efficacy issues. Treatment response to rTMS was shown to be related to changes in SICI that might reflect modulation of GABAergic mechanisms directly or indirectly related to rTMS treatment effects.

Trauma-associated tinnitus.

BACKGROUND: Up to 53% of individuals suffering from traumatic brain injuries develop tinnitus. OBJECTIVE: To review the current literature on trauma-associated tinnitus in order to provide orientation for the clinical management of patients with trauma-associated tinnitus. MATERIALS: A systematic literature search has been conducted in PubMed database applying the search terms posttraumatic tinnitus and trauma-associated tinnitus. Results have been complemented by related studies, book chapters, and the authors' clinical experience. RESULTS: Not only mechanical, pressure-related, or noise-related head traumata but also neck injuries and emotional trauma can cause tinnitus. Exact diagnosis is essential. Disorders such as ossicular chain disruption, traumatic eardrum perforation, or perilymphatic fistula can be surgically treated. It should also be considered that pulsatile tinnitus can be a sign of life-threatening disorders such as carotid cavernous fistulas, arteriovenous malformations, and carotid dissections. Also, posttraumatic stress disorder should be taken into consideration as a potential contributing factor. CONCLUSIONS: There is an evident mismatch between the high incidence of trauma-associated tinnitus and scarce literature on the topic. A consistent and-at best-standardized assessment of tinnitus- and hearing-related sequelae of trauma is recommended both for the improvement of clinical care and for a deeper understanding of the various pathophysiological mechanisms of trauma-associated tinnitus.

Is there a link between tinnitus and temporomandibular disorders?

STATEMENT OF PROBLEM: The frequent concurrence of tinnitus and temporomandibular joint and masticatory muscle disorders (TMD) has led to the assumption that a possible relationship exists between these 2 conditions. PURPOSE: The present prospective clinical study was conducted to assess the possible association between tinnitus and TMD and to investigate the effect of stomatognathic therapy on tinnitus distress. MATERIAL AND METHODS: The prevalence of TMD and tinnitus was investigated in a consecutive series of 951 patients at the Department of Prosthetic Dentistry at the University Medical Center Regensburg, Germany. Patients with TMD and simultaneous tinnitus were included in the prospective clinical trial (n=25). Baseline examination comprised a detailed functional analysis, diagnosis of temporomandibular joint and masticatory muscle disorder, and a tinnitus questionnaire. All the participants received individual dental functional therapy (oral splints, physiotherapy). The effects of functional therapy on TMD and tinnitus symptoms were examined 3 to 5 months after the initiation of dental functional therapy. Means (standard deviations) were calculated, and 1-way ANOVA was used to investigate statistical differences (α=.05). The differences of the 2 binary outcomes were compared with the Pearson χ(2) test, and the relative risk was calculated. RESULTS: Prevalence of tinnitus was found to be 8 times higher in participants with TMD (30 of 82 [36.6%]) than in participants without TMD (38 of 869 [4.4%]). All the participants with unilateral TMD and unilateral tinnitus showed these conditions on the same side. Stomatognathic therapy improved tinnitus symptoms in 11 of 25 participants (44%). CONCLUSIONS: The results of this study and the prospective clinical trial showed a significant correlation between tinnitus and TMD. The observed treatment outcome suggests that dental functional therapy may have a positive effect on TMD-related tinnitus.

Tinnitus: Clinical Insights in Its Pathophysiology-A Perspective.

Tinnitus, the perception of sound without a corresponding external sound source, and tinnitus disorder, which is tinnitus with associated suffering, present a multifaceted clinical challenge due to its heterogeneity and its incompletely understood pathophysiology and especially due to the limited therapeutic options. In this narrative review, we give an overview on various clinical aspects of tinnitus including its heterogeneity, contributing factors, comorbidities and therapeutic pathways with a specific emphasis on the implications for its pathophysiology and future research directions. Tinnitus exhibits high perceptual variability between affected individuals (heterogeneity) and within affected individuals (temporal variability). Hearing loss emerges as predominant risk factor and the perceived pitch corresponds to areas of hearing loss, supporting the compensatory response theory. Whereas most people who have tinnitus can live a normal life, in 10-20% tinnitus interferes severely with quality of life. These patients suffer frequently from comorbidities such as anxiety, depression or insomnia, acting as both risk factors and consequences. Accordingly, neuroimaging studies demonstrate shared brain networks between tinnitus and stress-related disorders shedding light on the intricate interplay of mental health and tinnitus. The challenge lies in deciphering causative relationships and shared pathophysiological mechanisms. Stress, external sounds, time of day, head movements, distraction, and sleep quality can impact tinnitus perception. Understanding these factors provides insights into the interplay with autonomic, sensory, motor, and cognitive processes. Counselling and cognitive-behavioural therapy demonstrate efficacy in reducing suffering, supporting the involvement of stress and anxiety-related networks. Hearing improvement, especially through cochlear implants, reduces tinnitus and thus indirectly validates the compensatory nature of tinnitus. Brain stimulation techniques can modulate the suffering of tinnitus, presumably by alteration of stress-related brain networks. Continued research is crucial for unravelling the complexities of tinnitus. Progress in management hinges on decoding diverse manifestations, identifying treatment-responsive subtypes, and advancing targeted therapeutic approaches.

The Current State of Tinnitus Diagnosis and Treatment: a Multidisciplinary Expert Perspective.

Tinnitus, the perception of sound without an external source, affects 15% of the population, with 2.4% experiencing significant distress. In this review, we summarize the current state of knowledge about tinnitus management with a particular focus on the translation into clinical practice. In the first section, we analyze shortcomings, knowledge gaps, and challenges in the field of tinnitus research. Then, we highlight the relevance of the diagnostic process to account for tinnitus heterogeneity and to identify all relevant aspects of the tinnitus in an individual patient, such as etiological aspects, pathophysiological mechanisms, factors that contribute most to suffering, and comorbidities. In the next section, we review available treatment options, including counselling, cognitive-behavioral therapy (CBT), hearing aids and cochlear implants for patients with a relevant hearing loss, sound generators, novel auditory stimulation approaches, tinnitus retraining therapy (TRT), pharmacological treatment, neurofeedback, brain stimulation, bimodal stimulation, Internet- and app-based digital approaches, and alternative treatment approaches. The evidence for the effectiveness of the various treatment interventions varies considerably. We also discuss differences in current respective guideline recommendations and close with a discussion of how current pathophysiological knowledge, latest scientific evidence, and patient perspectives can be translated in patient-centered care.

Auditory Cortical Plasticity in Patients with Single-Sided Deafness Before and After Cochlear Implantation.

PURPOSE: This study investigated neuroplastic changes induced by postlingual single-sided deafness (SSD) and the effects of a cochlear implantation for the deaf ear. Neural processing of acoustic signals from the normal hearing ear to the brain was studied before and after implantation using a positron emission tomography (PET)/CT scanner. METHODS: Eight patients with postlingual SSD received a cochlear implant (CI) in a prospective clinical trial. Dynamic imaging was performed in a PET/CT scanner using radioactively labeled water ([15O]H2O) to localize changes in the regional cerebral blood flow (rCBF) with and without an auditory task of logatomes containing speech-like elements without meaningful context. The normal hearing ear was stimulated before implantation and after the use of the cochlear implant for at least 8 months (mean 13.5, range 8.1-26.6). Eight age- and gender-matched subjects with normal hearing on both sides served as healthy control subjects (HCS). RESULTS: When the normal hearing ear of SSD patients was stimulated before CI implantation, the [15O]H2O-PET showed a more symmetrical rCBF in the auditory regions of both hemispheres in comparison to the HCS. The use of CI increased the asymmetry index (AI) in six of eight patients indicating an increase of activity of the contralateral hemisphere. Non-parametric statistics revealed a significant difference in the AI between patients before CI implantation and HCS (p < .01), which disappeared after CI implantation (p = .195). CONCLUSION: The functional neuroimaging data showed a tendency towards normalization of neuronal activity after CI implantation, which supports the effectiveness of CI in SSD patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01749592, December 13, 2012.

Neural correlates of tinnitus duration and distress: a positron emission tomography study.

Cerebral (18)F-deoxyglucose positron emission tomography (FDG-PET) has shown altered auditory pathway activity in tinnitus. However, the corresponding studies involved only small samples and analyses were restricted to the auditory cortex in most studies. Evidence is growing that also limbic, frontal, and parietal areas are involved in the pathophysiology of chronic tinnitus. These regions are considered to mediate perceptual, attentional, and emotional processes. Thus, the aim of the present study was the systematic evaluation of metabolic brain activity in a large sample of tinnitus patients. Ninety one patients with chronic tinnitus underwent FDG-PET. The effects of tinnitus severity (assessed by a tinnitus questionnaire score), duration and laterality were evaluated with statistical parametric mapping (SPM) in whole brain analyses. In addition, region of interest analyses were performed for primary auditory areas. Tinnitus duration correlated positively with brain metabolism in right inferior frontal, right ventro-medial prefrontal, and right posterior cingulate cortex. Tinnitus distress correlated positively with activation of left and right posterior inferior temporal gyrus as well as left and right posterior parahippocampal-hippocampal interface. Region of interest analysis demonstrated an overactivation of left in contrast to right Heschl's gyrus independently from tinnitus laterality and anatomical hemispheric differences. Tinnitus duration and distress were associated with areas involved in attentional and emotional processing. This is in line with recent findings indicating the relevance of higher order areas in the pathophysiology of tinnitus. Earlier results of asymmetric activation of the auditory cortices in tinnitus were confirmed, i.e., left-sided overactivation was found independently from tinnitus laterality.

Neurofeedback for tinnitus treatment: an innovative method with promising potential.

This scientific commentary refers to 'Does it matter what is trained? A randomized controlled trial evaluating the specificity of alpha/delta ratio neurofeedback in reducing tinnitus symptoms 'by Jensen et al. (https://doi.org/10.1093/braincomms/fcad185).

Tinnitus Guidelines and Their Evidence Base.

Evidence-based medicine (EBM) is generally accepted as the gold standard for high-quality medicine and, thus, for managing patients with tinnitus. EBM integrates the best available scientific information with clinical experience and patient values to guide decision-making about clinical management. To help health care providers and clinicians, the available evidence is commonly translated into medical or clinical guidelines based on a consensus. These involve a systematic review of the literature and meta-analytic aggregation of research findings followed by the formulation of clinical recommendations. However, this approach also has limitations, which include a lack of consideration of individual patient characteristics, the susceptibility of guideline recommendations to material and immaterial conflicts of interest of guideline authors and long latencies till new knowledge is implemented in guidelines. A further important aspect in interpreting the existing literature is that the absence of evidence is not evidence of absence. These circumstances could result in the decoupling of recommendations and their supporting evidence, which becomes evident when guidelines from different countries differ in their recommendations. This opinion paper will discuss how these weaknesses can be addressed in tinnitus.

Deficient central mechanisms in tinnitus: Exploring the impact on speech comprehension and executive functions.

Many individuals with chronic subjective tinnitus report significant problems in comprehending speech in adverse listening situations. A large body of studies has provided evidence to support the notion that deficits in speech-in-noise (SIN) are prevalent in the tinnitus population, while some studies have challenged these findings. Elemental auditory perception is usually only minimally or not impaired. In addition, deficits in cognitive functions, particularly executive functions, have also been observed in individuals with tinnitus. Given these previous findings, we theorize that deficient central mechanisms may be responsible for the reported speech comprehension problems in tinnitus. 25 participants suffering from chronic subjective tinnitus and 25 control participants, between 23 and 58 years of age, were examined in a cross-sectional design. The groups were case-matched for age, sex, education, and hearing loss. A large audiometric battery was used ranging from threshold and supra-threshold tasks to spoken sentence level speech tasks. Additionally, four cognitive tests were performed, primarily covering the area of executive functions. Tinnitometry and tinnitus-related questionnaires were applied to complement sample description and allow for secondary analyses. We hypothesized that tinnitus participants score lower in complex speech comprehension tasks and executive function tasks compared to healthy controls, while no group differences in elementary audiometric tasks were expected. As expected, individuals with chronic subjective tinnitus scored lower in the SIN and gated speech task, while there were no differences in the basic speech recognition threshold task and the other elementary auditory perception tasks. The cognitive tests revealed clear deficits in interference control in the Stroop task, but not in the Flanker task, in the tinnitus group. There were no differences in inhibition or working memory tasks. Our results clearly delineate differences between tinnitus individuals and control participants in two tests on speech intelligibility under adverse listening conditions. Further, the poorer performance in a task of interference control in individuals with tinnitus points towards an impaired central executive control in individuals with tinnitus. Taken together, our (partly) exploratory study provides novel evidence to the view that deficient central executive system in individuals with tinnitus probably account for impaired speech comprehension.

Radiological feature heterogeneity supports etiological diversity among patient groups in Meniere's disease.

We aimed to determine the prevalence of radiological temporal bone features that in previous studies showed only a weak or an inconsistent association with the clinical diagnosis of Meniere's disease (MD), in two groups of MD patients (n = 71) with previously established distinct endolymphatic sac pathologies; i.e. the group MD-dg (ES degeneration) and the group MD-hp (ES hypoplasia). Delayed gadolinium-enhanced MRI and high-resolution CT data were used to determine and compare between and within (affected vs. non-affected side) groups geometric temporal bone features (lengths, widths, contours), air cell tract volume, height of the jugular bulb, sigmoid sinus width, and MRI signal intensity alterations of the ES. Temporal bone features with significant intergroup differences were the retrolabyrinthine bone thickness (1.04 ± 0.69 mm, MD-hp; 3.1 ± 1.9 mm, MD-dg; p < 0.0001); posterior contour tortuosity (mean arch-to-chord ratio 1.019 ± 0.013, MD-hp; 1.096 ± 0.038, MD-dg; p < 0.0001); and the pneumatized volume (1.37 [0.86] cm3, MD-hp; 5.25 [3.45] cm3, MD-dg; p = 0.03). Features with differences between the affected and non-affected sides within the MD-dg group were the sigmoid sinus width (6.5 ± 1.7 mm, affected; 7.6 ± 2.1 mm, non-affected; p = 0.04) and the MRI signal intensity of the endolymphatic sac (median signal intensity, affected vs. unaffected side, 0.59 [IQR 0.31-0.89]). Radiological temporal bone features known to be only weakly or inconsistently associated with the clinical diagnosis MD, are highly prevalent in either of two MD patient groups. These results support the existence of diverse-developmental and degenerative-disease etiologies manifesting with distinct radiological temporal bone abnormalities.