Otoacoustic emissions in African mole-rats.

African mole-rats display highly derived hearing that is characterized by low sensitivity and a narrow auditory range restricted to low frequencies < 10 kHz. Recently, it has been suggested that two species of these rodents do not exhibit distortion product otoacoustic emissions (DPOAE), which was interpreted as evidence for a lack of cochlear amplification. If true, this would make them unique among mammals. However, both theoretical considerations on the generation of DPOAE as well as previously published experimental evidence challenge this assumption. We measured DPOAE and stimulus-frequency otoacoustic emissions (SFOAE) in three species of African mole-rats (Ansell's mole-rat - Fukomys anselli; Mashona mole-rat - Fukomys darlingi; naked mole-rat - Heterocephalus glaber) and found unexceptional otoacoustic emission values. Measurements were complicated by the remarkably long, narrow and curved external ear canals of these animals, for which we provide a morphological description. Both DPOAE and SFOAE displayed the highest amplitudes near 1 kHz, which corresponds to the region of best hearing in all tested species, as well as to the frequency region of the low-frequency acoustic fovea previously described in Ansell's mole-rat. Thus, the cochlea in African mole-rats shares the ability to generate evoked otoacoustic emission with other mammals.

Performance of ear canal sound measurements in detecting dural arteriovenous fistulas.

OBJECTIVE: Patients with pulsatile tinnitus (PT) are often referred for digital subtraction angiography (DSA) to exclude cranial dural arteriovenous fistula (DAVF). Because DSA is not without risk, the authors studied the sensitivity and specificity of an automated detection algorithm that analyses external ear canal sound measurements to evaluate the presence of DAVF in PT patients. METHODS: Between 2015 and 2021, external ear canal sound measurements of 72 PT patients were collected prospectively at our tertiary tinnitus clinic preceding referral of these patients to the neurosurgical department for counseling about DSA. The measurements were analyzed with an algorithm that objectifies a pulsatile sound as a PT coherence index (PTCI) per frequency band. RESULTS: Ultimately, DSA was performed in 49 PT patients. DAVF was revealed in 15 patients (31%). PTCI cutoff values of 0.7 (at 250 Hz) and 0.6 (at 1000 Hz) resulted in sensitivity of 100% (78%-100%) and specificities of 62% (44%-78%) and 68% (49%-83%), respectively, for detecting DAVF on DSA. CONCLUSIONS: Analysis of external ear canal sound measurements in PT patients showed 100% sensitivity for detecting DAVF on DSA. This analysis can potentially be used as a screening tool to help clinicians and PT patients to decide on the necessity of DSA. Retrospectively, the use of sound measurement in our cohort would have narrowed the indication for DSA to 23 of 49 cases (47%) without missing a DAVF.

The effect of preoperative oral nutritional supplementation on surgical site infections among adult patients undergoing elective surgery: A systematic review and meta-analysis.

INTRODUCTION: Mixed findings are reported on the effect of oral nutritional supplements in reducing Surgical Site Infections (SSIs). MATERIAL AND METHODS: PubMED, EMBASE and Cochrane were searched. Studies from inception to July 2022 were included if they involved adults undergoing elective surgery and compared preoperative macronutrient oral nutritional supplements to placebo/standard diet. RESULTS: Of 372 unique citations, 19 were included (N â€‹= â€‹2480): 13 RCTs (N â€‹= â€‹1506) and 6 observational studies (N â€‹= â€‹974). Moderate-certainty evidence suggested that nutritional supplements SSI risk (OR 0.54, 95% C.I. 0.40-0.72, N â€‹= â€‹2718 participants). In elective colorectal surgery, this risk-reduction was 0.43 (95% C.I. 0.26-0.61, N â€‹= â€‹835 participants) and among patients who received Impact 0.48 (95% C.I. 0.32-0.70, N â€‹= â€‹1338). CONCLUSION: Oral nutritional supplements prior to adult elective surgery may significantly reduce SSIs, with an overall 50% protective effect. This protective effect persisted in subgroup analysis of colorectal surgery patients and the use of Impact.

Hyperacusis is associated with smaller gray matter volumes in the supplementary motor area.

Hyperacusis is a disorder in loudness perception characterized by increased sensitivity to ordinary environmental sounds and associated with otologic conditions, including hearing loss and tinnitus (the phantom perception of sound) as well as neurologic and neuropsychiatric conditions. Hyperacusis is believed to arise centrally in the brain; however, the underlying causes are unknown. To gain insight into differences in brain morphology associated with hyperacusis, we undertook a retrospective case-control study comparing whole-brain gray matter morphology in participants with sensorineural hearing loss and tinnitus who either scored above or below the threshold for hyperacusis based on a standard questionnaire. We found that participants reporting hyperacusis had smaller gray matter volumes and cortical sheet thicknesses in the right supplementary motor area (SMA), independent of anxiety, depression, tinnitus burden, or sex. In fact, the right SMA volumes extracted from an independently defined volume of interest could accurately classify participants. Finally, in a subset of participants where functional data were also available, we found that individuals with hyperacusis showed increased sound-evoked responses in the right SMA compared to individuals without hyperacusis. Given the role of the SMA in initiating motion, these results suggest that in hyperacusis the SMA is involved in a motor response to sounds.

Effects of Physical Interventions on Subjective Tinnitus, a Systematic Review and Meta-Analysis.

Increasingly, patients suffering from subjective tinnitus seek help from physical therapists. Numerous randomised controlled trials (RCTs) have investigated the effect of physical interventions commonly used in physical therapy practice on subjective tinnitus. This systematic review and meta-analysis aimed to analyse the effects of physical interventions on tinnitus loudness, tinnitus annoyance, and scores on the Tinnitus Handicap Index (THI). Four databases were searched from inception up to March 2022. A total of 39 RCTs were included in the systematic review, and 23 studies were appropriate for meta-analyses. Risk of bias assessments were also performed. Interventions analysed in at least five studies were summarised, including transcutaneous electrical nerve stimulation (TENS), laser therapy, and acupuncture. Random-effects meta-analysis models were used, and effect sizes were expressed as Hedge's standardised mean differences (SMD) with 95%CI's. The quality of three-quarters of the studies was limited due to insufficient allocation concealment, lack of adequate blinding, and small sample sizes. Large, pooled effects sizes were found for acupuncture (SMD: 1.34; 95%CI: 0.79, 1.88) and TENS (SMD: 1.17; 95%CI: 0.48, 1.87) on THI as well as for acupuncture on tinnitus loudness (VAS Loudness (SMD: 0.84; 95%CI: 0.33, 1.36) and tinnitus annoyance (SMD: 1.18; 95%CI: 0.00, 2.35). There is some evidence that physical interventions (TENS and acupuncture, but not laser therapy) may be effective for tinnitus. However, the lack of high-quality studies and the risk of bias in many studies prohibits stronger conclusions.

Hallucinations in Hearing Impairment: How Informed Are Clinicians?

BACKGROUND AND HYPOTHESIS: Patients with hearing impairment (HI) may experience hearing sounds without external sources, ranging from random meaningless noises (tinnitus) to music and other auditory hallucinations (AHs) with meaningful qualities. To ensure appropriate assessment and management, clinicians need to be aware of these phenomena. However, sensory impairment studies have shown that such clinical awareness is low. STUDY DESIGN: An online survey was conducted investigating awareness of AHs among clinicians and their opinions about these hallucinations. STUDY RESULTS: In total, 125 clinicians (68.8% audiologists; 18.4% Ear-Nose-Throat [ENT] specialists) across 10 countries participated in the survey. The majority (96.8%) was at least slightly aware of AHs in HI. About 69.6% of participants reported encountering patients with AHs less than once every 6 months in their clinic. Awareness was significantly associated with clinicians' belief that patients feel anxious about their hallucinations (ß = .018, t(118) = 2.47, P < .01), their belief that clinicians should be more aware of these hallucinations (ß =.018, t(118) = 2.60, P < .01), and with confidence of clinicians in their skills to assess them (ß = .017, t(118) = 2.63, P < .01). Clinicians felt underequipped to treat AHs (Median = 31; U = 1838; PFDRadj < .01). CONCLUSIONS: Awareness of AHs among the surveyed clinicians was high. Yet, the low frequency of encounters with hallucinating patients and their belief in music as the most commonly perceived sound suggest unreported cases. Clinicians in this study expressed a lack of confidence regarding the assessment and treatment of AHs and welcome more information.

Comparison between two self-guided tinnitus pitch matching methods.

Introduction: Tinnitus pitch matching is a procedure by which the frequency of an external sound is manipulated in such a way that its pitch matches the one of the tinnitus. The correct measure of the tinnitus pitch plays an important role in the effectiveness of any sound-based therapies. To date, this assessment is difficult due to the subjective nature of tinnitus. Some of the existing pitch matching methods present a challenge for both patients and clinicians, and require multiple adjustments of frequency and loudness, which becomes increasingly difficult in case of coexisting hearing loss. In this paper, we present the comparison in terms of reliability between two self-guided pitch matching methods: the method of adjustment (MOA) and the multiple-choice method (MCM). Methods: 20 participants with chronic tinnitus and hearing loss underwent the two assessments in two different sessions, 1 week apart. Measures of intraclass correlation (ICC) and difference in octaves (OD) within-method and within-session were obtained. Results: Both methods presented good reliability, and the obtained values of ICC and OD suggested that both methods might measure a different aspect of tinnitus. Discussion: Our results suggest that a multiple-choice method (MCM) for tinnitus pitch matching is as reliable in a clinical population as more conventional methods.

Performance of an Automated Detection Algorithm to Assess Objective Pulsatile Tinnitus.

OBJECTIVES: In this paper we describe an automated detection algorithm that objectively detects pulsatile tinnitus (PT) and investigate its performance. DESIGN: Sound measurements were made with a sensitive microphone placed in the outer ear canal in 36 PT-patients referred to our tertiary clinic, along with a registration of the heart rate. A novel algorithm expressed the coherence between the recorded sound and heart rate as a pulsatility index. This index was determined for 6 octave bands of the recorded sound. We assessed the performance of the detection algorithm by comparing it with the judgement of 3 blinded observers. RESULTS: The algorithm showed good agreement compared with the majority judgement of the blinded observers (ROC AUC 0.83). Interobserver reliability for detecting PT in sound recordings by the three blinded observers was substantial (Fleiss's κ=0.64). CONCLUSIONS: The algorithm may be a reliable alternative to subjective assessments of in-canal sound measurements in PT-patients, thus providing clinicians with an objective measure to differentiate between subjective and objective pulsatile tinnitus.

A Combined Image- and Coordinate-Based Meta-Analysis of Whole-Brain Voxel-Based Morphometry Studies Investigating Subjective Tinnitus.

Previous voxel-based morphometry (VBM) studies investigating tinnitus have reported structural differences in a variety of spatially distinct gray matter regions. However, the results have been highly inconsistent and sometimes contradictory. In the current study, we conducted a combined image- and coordinate-based meta-analysis of VBM studies investigating tinnitus to identify robust gray matter differences associated with tinnitus, as well as examine the possible effects of hearing loss on the outcome of the meta-analysis. The PubMed and Web of Science databases were searched for studies published up to August 2021. Additional manual searches were conducted for studies published up to December 2021. A whole-brain meta-analysis was performed using Seed-Based d Mapping with Permutation of Subject Images (SDM-PSI). Fifteen studies comprising 423 individuals with tinnitus and either normal hearing or hearing loss (mean age 50.94 years; 173 females) and 508 individuals without tinnitus and either normal hearing or hearing loss (mean age 51.59 years; 234 females) met the inclusion criteria. We found a small but significant reduction in gray matter in the left inferior temporal gyrus for groups of normal hearing individuals with tinnitus compared to groups of hearing-matched individuals without tinnitus. In sharp contrast, in groups with hearing loss, tinnitus was associated with increased gray matter levels in the bilateral lingual gyrus and the bilateral precuneus. Those results were dependent upon matching the hearing levels between the groups with or without tinnitus. The current investigation suggests that hearing loss is the driving force of changes in cortical gray matter across individuals with and without tinnitus. Future studies should carefully account for confounders, including hearing loss, hyperacusis, anxiety, and depression, to identify gray matter changes specifically related to tinnitus. Ultimately, the aggregation of standardized individual datasets with both anatomical and useful phenotypical information will permit a better understanding of tinnitus-related gray matter differences, the effects of potential comorbidities, and their interactions with tinnitus.

Cerebellar Gray Matter Volume in Tinnitus.

Tinnitus is the perception of sound without an external source. The flocculus (FL) and paraflocculus (PFL), which are small lobules of the cerebellum, have recently been implicated in its pathophysiology. In a previous study, the volume of the (P)FL-complex correlated with tinnitus severity in patients that had undergone cerebellopontine angle (CPA) tumor removal. In this study, the relation between tinnitus and gray matter volume (GMV) of the (P)FL-complex, GMV of the other cerebellar lobules and GMV of the cerebellar nuclei is investigated in otherwise healthy participants. Data was processed using the SUIT toolbox, which is dedicated to analysis of imaging data of the human cerebellum. GMV of all cerebellar lobules and nuclei were similar between tinnitus and non-tinnitus participants. Moreover, no relation was present between tinnitus severity, as measured by the Tinnitus Handicap Inventory, and (P)FL-complex GMV, tonsil GMV, or total cerebellar cortical GMV. These results suggest that in otherwise healthy participants, in contrast to participants after CPA tumor removal, no relation between the GMV of neither the (P)FL-complex nor other cerebellar lobules and tinnitus presence and severity exists. These findings indicate that a relation only exists when the (P)FL-complex is damaged, for instance by a CPA tumor. Alternatively, it is possible that differences in (P)FL-complex GMVs are too small to detect with a voxel-based morphometry study. Therefore, the role of the (P)FL-complex in tinnitus remains to be further studied.

Carbamazepine induces upward frequency shifts of spontaneous otoacoustic emissions.

In three subjects, we measured spontaneous otoacoustic emissions (SOAEs) when they were using carbamazepine (CBZ), and compared this to the SOAE measurement when they were not using CBZ. We observed 14 SOAEs showing a consistent upward shift of center frequency, related to CBZ intake. On average, the magnitude of the frequency shift increased with increasing frequency. The magnitude of the shift was 30-104 Hz, at frequencies ranging from 1.3 to 2.3 kHz, corresponding to a shift between 2.3 and 4.5%. Compared to other causes and manipulations known to change SOAE frequency, these shifts are relatively large. The underlying mechanism is most likely an increased stiffness of the cochlear partition. This would also explain the downward pitch shift due to CBZ, which has been reported by subjects with absolute pitch.

Relationship between irregularities in spontaneous otoacoustic emissions suppression and psychophysical tuning curves.

The suppression of spontaneous otoacoustic emissions (SOAEs) allows the objective evaluation of cochlear frequency selectivity by determining the suppression tuning curve (STC). Interestingly, some STCs have additional sidelobes at the high frequency flank, which are thought to result from interaction between the probe tone and the cochlear standing wave corresponding to the SOAE being suppressed. Sidelobes are often in regions of other neighboring SOAEs but can also occur in the absence of any other SOAE. The aim of this study was to compare STCs and psychoacoustic tuning curves (PTCs). Therefore, STCs and PTCs were measured in: (1) subjects in which the STC had a sidelobe, and (2) subjects without STC sidelobes. Additionally, PTCs were measured in subjects without SOAEs. Across participant groups, the quality factor Q10dB of the PTCs was similar, independently from whether SOAEs were present or absent. Thus, the presence of an SOAE does not provide enhanced frequency selectivity at the emission frequency. Moreover, both PTC and STC show irregularities, but these are not related in a straightforward way. This suggests that different mechanisms cause these irregularities.

The Role of Inflammation in Tinnitus: A Systematic Review and Meta-Analysis.

Subjective tinnitus is the perception of sound without the presence of an external source. Increasing evidence suggests that tinnitus is associated with inflammation. In this systematic review, the role of inflammation in subjective tinnitus was studied. Nine animal and twenty human studies reporting inflammatory markers in both humans and animals with tinnitus were included. It was established that TNF-α and IL-1ß are increased in tinnitus, and that microglia and astrocytes are activated as well. Moreover, platelet activation may also play a role in tinnitus. In addition, we elaborate on mechanisms of inflammation in tinnitus, and discuss potential treatment options targeting inflammatory pathways.

A retrospective cross-sectional study on tinnitus prevalence and disease associations in the Dutch population-based cohort Lifelines.

Tinnitus is a highly prevalent disorder with heterogenous presentation and limited treatment options. Better understanding of its prevalence and disease and lifestyle risk factor associations in the general population is necessary to identify the underlying mechanisms. To this end, we quantified the prevalence of tinnitus and identified disease and lifestyle risk factors associated with tinnitus within a general population cohort. For this study, we used the Lifelines population-based cohort study to perform a retrospective cross-sectional study. Lifelines is a large, multi-generational, prospective cohort study that includes over 167,000 participants (or 10% of the population) from the northern Netherlands. For this study, conducted between 2018 and 2021, data from the Lifelines population-based cohort study was used to perform a cross-sectional study. Adult participants (age ≥ 18 years) with data on tinnitus perception (collected once between 2011 and 2015) were included in this study. An elastic-net regression analysis was performed with tinnitus as the dependent variable and parameters of diseases and lifestyle risk factors (collected once between 2006 and 2014)-including hearing problems, cardiovascular disease, metabolic disorders, psychiatric disorders, thyroid disease, inflammatory disease, and functional somatic syndromes-as the independent variables. Among 124,609 participants, N = 8,011 (6.4%) reported perceiving tinnitus constantly (CT: constant tinnitus) and N = 39,625 (31.8%) reported perceiving tinnitus constantly or occasionally (AT: any tinnitus). Our analysis identified 38 parameters that were associated with AT and 48 parameters that were associated with CT. Our study identified established disease associates with tinnitus, including problems with hearing (OR 8.570 with CT), arrythmia (OR 1.742 with CT), transient ischemic attack (OR 1.284 with AT), diabetes mellitus (OR 1.014 with AT) and psychiatric disorders, including major depressive disorder (OR 1.506 with CT). Factors related to lifestyle associated with tinnitus included waist-hip ratio (OR 1.061 with CT) and smoking (OR 1.028 with AT). Novel disease associates with CT were identified for inflammatory diseases, including rheumatoid arthritis (OR 1.297) and ulcerative colitis (OR 1.588), thyroid disease (as evidenced by the use of thyroid medication) (OR 1.298), and functional somatic syndromes, including chronic fatigue syndrome (OR 1.568). In addition to validating established disease associates in a general population cohort, this study identified novel associations with tinnitus and several disease categories, including functional somatic syndromes, inflammatory diseases, and thyroid disease. Future work will be necessary to identify whether (common) mechanisms underly tinnitus and these associated disorders. Lifelines is an important new resource available for future studies investigating tinnitus in the general population.

Too Blind to See the Elephant? Why Neuroscientists Ought to Be Interested in Tinnitus.

A curative therapy for tinnitus currently does not exist. One may actually exist but cannot currently be causally linked to tinnitus due to the lack of consistency of concepts about the neural correlate of tinnitus. Depending on predictions, these concepts would require either a suppression or enhancement of brain activity or an increase in inhibition or disinhibition. Although procedures with a potential to silence tinnitus may exist, the lack of rationale for their curative success hampers an optimization of therapeutic protocols. We discuss here six candidate contributors to tinnitus that have been suggested by a variety of scientific experts in the field and that were addressed in a virtual panel discussion at the ARO round table in February 2021. In this discussion, several potential tinnitus contributors were considered: (i) inhibitory circuits, (ii) attention, (iii) stress, (iv) unidentified sub-entities, (v) maladaptive information transmission, and (vi) minor cochlear deafferentation. Finally, (vii) some potential therapeutic approaches were discussed. The results of this discussion is reflected here in view of potential blind spots that may still remain and that have been ignored in most tinnitus literature. We strongly suggest to consider the high impact of connecting the controversial findings to unravel the whole complexity of the tinnitus phenomenon; an essential prerequisite for establishing suitable therapeutic approaches.

Validation of a Dutch version of the Tinnitus Functional Index in a tertiary referral tinnitus clinic.

INTRODUCTION: Tinnitus is a condition with a subjective nature that requires self-report questionnaires for its assessment. Aspects such as quality of life, sleep or intrusiveness have been addressed by multiple tinnitus questionnaires, but the high responsiveness to treatment effects of the Tinnitus Functional Index (TFI) makes this questionnaire part of the standard practice in tinnitus screening. To date, the TFI has been translated to more than 20 languages and used in more than 22 countries. In this study, the TFI was translated to Dutch and validated through a clinical population in the Netherlands. METHODS: After a back-translation procedure, the Dutch TFI was filled-out by 377 patients in the tinnitus outpatient clinic at the Ear, Nose and Throat (ENT) department of the University Medical Center Groningen, in the Netherlands. Reliability and construct validity of the questionnaire were assessed by correlations with one other tinnitus questionnaire (Tinnitus Handicap Inventory, THI) and with three psychological functioning questionnaires (Rand-36, Cantril's ladder and the Hospital Anxiety and Depression Scale (HADS)). The eight-factor structure of the Dutch TFI was tested by means of exploratory factor analysis using three different models (ICM-CFA, ESEM and ESEM-CFA). RESULTS: The Dutch TFI showed a high internal consistency (α = 0.95), and construct validity was proven by moderate-to high-convergent correlations with the THI (r = 0.47-0.79) and by moderate convergent (r = 0.55-0.67) and good-to moderate-divergent (r = 0.12-0.47) correlations with the psychological functioning questionnaires. The eight-factor structure of the TFI was confirmed for the Dutch version by the three models. CONCLUSION: The Dutch version of the TFI is a reliable instrument for screening tinnitus impact in a clinical population, and its psychometric properties are comparable to the original TFI and other validated tinnitus questionnaires.

Investigating the relation between minimum masking levels and hearing thresholds for tinnitus subtyping.

Heterogeneity of tinnitus imposes a challenge for its treatment. Identifying tinnitus subtypes might help to establish individualized diagnosis and therapies. The minimum masking level (MML) is a clinical tool defined as the minimum intensity of a masking sound required to cover tinnitus. Understanding the differences among masking patterns in patients could facilitate the task of subtyping tinnitus. Here, we studied the variability of hearing thresholds and MMLs among patients with tinnitus to identify tinnitus subgroups. A population of 366 consecutive patients from a specialized tinnitus clinic were included in the analysis. Hearing thresholds and MMLs were determined for octave frequencies from 0.25 to 8kHz, as well as for 3 and 6kHz. Subjects were divided into two groups according to whether their tinnitus was maskable (M, 329 subjects) or non-maskable (NM, 37 subjects). Hearing thresholds and tinnitus loudness did not differ significantly between both groups. The dimensionality of the data was reduced by means of principal component analysis (PCA), and the largest resulting components were used for clustering the data. The cluster analysis resulted in five clusters with differences in tinnitus pitch, lateralization, hearing thresholds and MML, as well as on age and gender. Clusters differed in contours of hearing thresholds and MML, describing patterns of low or high thresholds in combination with low or high MML. The clustering solution presented a low silhouette value (0.45), implying that the clustering is weak and could be artificial. The analysis pointed out the diversity across tinnitus patients. Our results suggest that there might be a continuum of patients' characteristics rather than discrete subgroups.

Macrostructural Changes of the Acoustic Radiation in Humans with Hearing Loss and Tinnitus Revealed with Fixel-Based Analysis.

Age-related hearing loss is the most prevalent sensory impairment in the older adult population and is related to noise-induced damage or age-related deterioration of the peripheral auditory system. Hearing loss may affect the central auditory pathway in the brain, which is a continuation of the peripheral auditory system located in the ear. A debilitating symptom that frequently co-occurs with hearing loss is tinnitus. Strikingly, investigations into the impact of acquired hearing loss, with and without tinnitus, on the human central auditory pathway are sparse. This study used diffusion-weighted imaging (DWI) to investigate changes in the largest central auditory tract, the acoustic radiation, related to hearing loss and tinnitus. Participants with hearing loss, with and without tinnitus, and a control group were included. Both conventional diffusion tensor analysis and higher-order fixel-based analysis were applied. The fixel-based analysis was used as a novel framework providing insight into the axonal density and macrostructural morphologic changes of the acoustic radiation in hearing loss and tinnitus. The results show tinnitus-related atrophy of the left acoustic radiation near the medial geniculate body. This finding may reflect a decrease in myelination of the auditory pathway, instigated by more profound peripheral deafferentation or reflecting a preexisting marker of tinnitus vulnerability. Furthermore, age was negatively correlated with the axonal density in the bilateral acoustic radiation. This loss of fiber density with age may contribute to poorer speech understanding observed in older adults.SIGNIFICANCE STATEMENT Age-related hearing loss is the most prevalent sensory impairment in the older adult population. Older individuals are subject to the cumulative effects of aging and noise exposure on the auditory system. A debilitating symptom that frequently co-occurs with hearing loss is tinnitus: the perception of a phantom sound. In this large DWI-study, we provide evidence that in hearing loss, the additional presence of tinnitus is related to degradation of the acoustic radiation. Additionally, older age was related to axonal loss in the acoustic radiation. It appears that older adults have the aggravating circumstances of age, hearing loss, and tinnitus on central auditory processing, which may partly be because of the observed deterioration of the acoustic radiation with age.