Phantom auditory perception (tinnitus): mechanisms of generation and perception

The role of hidden hearing loss in tinnitus: Insights from early markers of peripheral hearing damage

Since the presence of tinnitus is not always associated with audiometric hearing loss, it has been hypothesized that hidden hearing loss may act as a potential trigger for increased central gain along the neural pathway leading to tinnitus perception. In recent years, the study of hidden hearing loss has improved with the discovery of cochlear synaptopathy and several objective diagnostic markers. This study investigated three potential markers of peripheral hidden hearing loss in subjects with tinnitus: extended high-frequency audiometric thresholds, the auditory brainstem response, and the envelope following response. In addition, speech intelligibility was measured as a functional outcome measurement of hidden hearing loss. To account for age-related hidden hearing loss, participants were grouped according to age, presence of tinnitus, and audiometric thresholds. Group comparisons were conducted to differentiate between age- and tinnitus-related effects of hidden hearing loss. All three markers revealed age-related differences, whereas no differences were observed between the tinnitus and non-tinnitus groups. However, the older tinnitus group showed improved performance on low-pass filtered speech in noise tests compared to the older non-tinnitus group. These low-pass speech in noise scores were significantly correlated with tinnitus distress, as indicated using questionnaires, and could be related to the presence of hyperacusis. Based on our observations, cochlear synaptopathy does not appear to be the underlying cause of tinnitus. The improvement in low-pass speech-in-noise could be explained by enhanced temporal fine structure encoding or hyperacusis. Therefore, we recommend that future tinnitus research takes into account age-related factors, explores low-frequency encoding, and thoroughly assesses hyperacusis.

Tinnitus mechanisms and the need for an objective electrophysiological tinnitus test

Tinnitus, the perception of sound with no external auditory stimulus, is a complex, multifaceted, and potentially devastating disorder. Despite recent advances in our understanding of tinnitus, there are limited options for effective treatment. Tinnitus treatments are made more complicated by the lack of a test for tinnitus based on objectively measured physiological characteristics. Such an objective test would enable a greater understanding of tinnitus mechanisms and may lead to faster treatment development in both animal and human research. This review makes the argument that an objective tinnitus test, such as a non-invasive electrophysiological measure, is desperately needed. We review the current tinnitus assessment methods, the underlying neural correlates of tinnitus, the multiple tinnitus generation theories, and the previously investigated electrophysiological measurements of tinnitus. Finally, we propose an alternate objective test for tinnitus that may be valid in both animal and human subjects.

Investigating the effectiveness of music therapy combined with binaural beats on chronic tinnitus: A randomized controlled trial

BACKGROUND

Binaural beat stimulation (BBS) involve presenting two sinusoidal waves with specific frequency differences to induce neural changes in the brain, often used for mental state induction and symptom reduction. However, there are limited studies on its effectiveness for tinnitus. This study aimed to assess the effectiveness of combining binaural beats with music containing nature sounds for chronic tinnitus.

METHODS

A total of 30 men, aged 45.87 on average (SD = 8.09), who had chronic tinnitus and symmetrical mild to moderate hearing loss, were included in this study. The participants were randomly assigned to two groups: MT group (Music therapy; n = 15), which received relaxing music containing the sound of sea waves, and MT + BBS group (Music therapy plus binaural beats; n = 15), which received the same music combined with alpha frequency (8 Hz) binaural beats. The therapy sessions were conducted twice a day for 15 min, over a period of 4 weeks. Outcome measures, including the Tinnitus Handicap Inventory (THI), Tinnitus Functional Index (TFI), Hospital Anxiety and Depression Scale (HADS), Visual Analog Scale (VAS) and the pitch and loudness of tinnitus were administered before, immediately after, and during the three-month follow-up period.

RESULTS

The findings revealed improvements in loudness and annoyance VAS, as well as THI total and all subscale scores in both groups (p < 0.001). Additionally, TFI total score showed improvement in both groups (MT: p = 0.001; MT + BBS: p < 0.001) except for the sense of control subscale in both groups and the cognitive subscale in the MT group after the treatment and during the three-month follow-up period. Furthermore, both groups exhibited a decrease in scores for both subscales of HADS. However, there were no significant differences between the two groups in any of the measurement outcomes (p > 0.05), except for the emotional subscale scores of TFI (p = 0.049) and the functional subscale scores of THI (p = 0.034). In other words, during the follow-up period, the MT + BBS group exhibited lower scores in these two subscales compared to the MT group.

CONCLUSION

Although our study failed to demonstrate the superiority of combining binaural beats with music, both groups experienced significant improvements. This suggest that there are potential benefits to be gained from these types of stimuli. Given the sustained effect of both methods and the even greater improvements in follow-up observed in the binaural beats group for some scales, it seems that the changes in neural response and brain waves caused by our stimulations are persistent. This necessitates further research involving brain mapping, especially with longer follow-up durations.

Outcome measures of brainwave entrainment using delta wave stimulation in individuals with tinnitus having normal hearing sensitivity

OBJECTIVE

The current study aimed to evaluate the efficacy of delta frequency binaural beats stimulation in treatment of individuals with tinnitus having normal hearing sensitivity.

METHOD

Twenty-four individuals who reported bothersome tinnitus in the presence of clinically normal hearing were grouped into two (I and II). The group was provided with delta frequency binaural beats and II was provided with white noise stimulation (both of 20 min duration) for 30 days. Post 30 days, the re-assessment of tinnitus handicap, depression, anxiety, and quality of life parameters were performed and compared with that of pre-treatment scores.

RESULTS

A considerable reduction of tinnitus handicap scores, depression and anxiety levels were observed for both the groups, except for the quality-of-life parameters. However, few of the participants showed limited or negligible improvement post-treatment. On comparison of reduction of scores observed across the groups, there was a higher reduction of scores observed for group I when compared to group II.

CONCLUSION

The current study was an initial attempt to study the efficacy of binaural beats in treatment of individuals with tinnitus having normal hearing. Apart from a few individuals, the delta wave stimulation acted as a helpful tool in improving tinnitus borne distress symptoms in such patients with normal hearing. The results of the present study put forward the scope of adapting binaural beats stimulation for the treatment of individuals presenting with tinnitus having normal hearing sensitivity. This technique could be adopted into clinical practice after extensive research involving an extended treatment duration on a larger population.

Tinnitus update: what can be done for the ringing?

Physicians will frequently encounter patients who report tinnitus. Tinnitus is a symptom whereby there is the perception of sound or sounds in the ear or head in the absence of an external source of sound. Most individuals experiencing tinnitus will have a neutral reaction to the percept, but in a small proportion of patients, tinnitus can be a debilitating symptom. When it causes burden, patients can be affected in multiple different facets of life, including impairment in sleep, hearing cognition and psychological and psychiatric well-being, often resulting in high healthcare utilisation and societal costs. Hence, chronic, disabling tinnitus is a complex condition with multifactorial causes and multiple perpetuating biopsychosocial factors. Despite efforts to increase knowledge about its pathophysiology and research into treatments, little impact on real-world clinical practice has been seen. There are no proven effective pharmacological treatments or complementary medicines specifically for chronic, disabling tinnitus. Despite this, there is a role for treating this condition through a multidisciplinary approach specifically targeting comorbid active psychiatric conditions, using hearing aids in appropriate clinical settings such as in those with a coassociated confirmed hearing loss, and specialised cognitive behavioural therapy for patients reporting bothersome tinnitus. Cognitive behavioural therapy remains the most valuable evidence-based intervention in this regard. This narrative review attempts to summarise the current understanding in terms of pathophysiology, assessment and treatment of tinnitus for the internal physician who may encounter patients with disabling, chronic tinnitus.

Background and Rationale for a Transitional Intervention for Debilitating Hyperacusis

PURPOSE

This report provides the experimental, clinical, theoretical, and historical background that motivated a patented transitional intervention and its implementation and evaluation in a field trial for mitigation of debilitating loudness-based hyperacusis (LH).

BACKGROUND AND RATIONALE

Barriers for ameliorating LH, which is differentiated here from other forms of hyperacusis, are delineated, including counterproductive management and treatment strategies that may exacerbate the condition. Evidence for hyper-gain central auditory processes as the bases for LH and the associated LH-induced distress and stress responses are presented. This presentation is followed by an overview of prior efforts to use counseling and therapeutic sound as interventional tools for recalibrating the hyper-gain LH response. We also consider previous efforts to use output-limiting sound-protection devices in the management of LH. This historical background lays the foundation for our transitional intervention protocol and its implementation and evaluation in a field trial.

CONCLUSIONS

The successful implementation and evaluation of a transitional intervention, which we document in the outcomes of a companion proof-of-concept field trial in this issue, build on our prior efforts and those of others to understand, manage, and treat hyperacusis. These efforts to overcome significant barriers and vexing long-standing challenges in the management and treatment of LH, as reviewed here, are the pillars of the transitional intervention and its primary components, namely, counseling combined with protective sound management and therapeutic sound, which we detail in separate reports in this issue.

Bridging the Gap between Psychophysiological and Audiological Factors in the Assessment of Tinnitus: An EEG Investigation in the Beta Band

BACKGROUND

Despite substantial progress in investigating its psychophysical complexity, tinnitus remains a scientific and clinical enigma. The present study, through an ecological and multidisciplinary approach, aims to identify associations between electroencephalographic (EEG) and psycho-audiological variables.

METHODS

EEG beta activity, often related to stress and anxiety, was acquired from 12 tinnitus patients (TIN group) and 7 controls (CONT group) during an audio cognitive task and at rest. We also investigated psychological (SCL-90-R; STAI-Y; BFI-10) and audiological (THI; TQ12-I; Hyperacusis) variables using non-parametric statistics to assess differences and relationships between and within groups.

RESULTS

In the TIN group, frontal beta activity positively correlated with hyperacusis, parietal activity, and trait anxiety; the latter is also associated with depression in CONT. Significant differences in paranoid ideation and openness were found between groups.

CONCLUSIONS

The connection between anxiety trait, beta activity in the fronto-parietal cortices and hyperacusis provides insights into brain functioning in tinnitus patients, offering quantitative descriptions for clinicians and new multidisciplinary treatment hypotheses.

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.

Prevalence and management outcomes of tonic tensor tympani syndrome in an ENT audiology tinnitus clinic in Singapore

OBJECTIVE

Tonic tensor tympani syndrome is found in a subset of tinnitus patients who experience intra-aural and peri-aural symptoms, in addition to their tinnitus, in the absence of clinically detectable pathology. As the syndrome has not been widely reported, this study aims to determine its prevalence and evaluate the effectiveness of current management.

METHODS

The tinnitus management clinic records of patients over the past six years were assessed to identify tonic tensor tympani syndrome patients and track their progress based on patient-reported Tinnitus Handicap Index scores. Patients with reversible ear pathology and temporomandibular joint disorder were excluded.

RESULTS

It was found that 13 per cent of the tinnitus management patients fulfilled the criteria for tonic tensor tympani syndrome and 94 per cent of those who returned for follow up showed an improvement in their Tinnitus Handicap Index grades.

CONCLUSION

This study suggests that tonic tensor tympani syndrome is a significant problem among tinnitus patients and current tinnitus management strategies contribute effectively to helping such patients habituate to their symptoms.

Associations Between Traumatic Brain Injury and Severity of Tinnitus-Related Functional Impairment Among US Military Veterans: A National, Population-Based Study

OBJECTIVE

To describe associations between a history of traumatic brain injury (TBI) and the severity of tinnitus-related functional impairment among a national, stratified random sample of veterans diagnosed with tinnitus by the Department of Veterans Affairs (VA) healthcare system.

SETTING

A multimodal (mailed and internet) survey administered in 2018. Participants: VA healthcare-using veterans diagnosed with tinnitus; veterans with comorbid TBI diagnosis were oversampled.

DESIGN

A population-based survey.

MAIN MEASURES

TBI history was assessed using International Classification of Diseases (ICD) diagnosis codes in veterans' VA electronic health records. The severity of participants' overall tinnitus-related functional impairment was measured using the Tinnitus Functional Index. Population prevalence and 95% confidence intervals (CIs) were estimated using inverse probability weights accounting for sample stratification and survey nonresponse. Veterans' relative risk ratios of very severe or moderate/severe tinnitus-related functional impairment, versus none/mild impairment, were estimated by TBI history using bivariable and multivariable multinomial logistic regression.

RESULTS

The population prevalence of TBI was 5.6% (95% CI: 4.8-6.4) among veterans diagnosed with tinnitus. Veterans with a TBI diagnosis, compared with those without a TBI diagnosis, had 3.6 times greater likelihood of rating their tinnitus-related impairment as very severe (95% CI: 2.1-6.3), and 1.5 times greater likelihood of rating their impairment as moderate/severe (95% CI: 1.0-2.4), versus none/mild.

CONCLUSIONS

These findings suggest an important role of TBI in the severity of tinnitus-related functional impairment among veterans. This knowledge can help inform the integration of tinnitus management services into the care received by veterans with TBI.

Current understanding of subjective tinnitus in adults

PURPOSE

An up-to-date overview of epidemiology, etiology and pathophysiological mechanisms, diagnostic and evaluation methods, current treatment status and future directions of subjective tinnitus in adults.

METHODS

Review of current evidence-based literature on subjective tinnitus in adults.

RESULTS

The prevalence of subjective tinnitus in the adult population is estimated to be around 14%, and it tends to increase with age. Subjective tinnitus is a complex condition with multiple factors contributing to its origin. However, the exact causes and underlying mechanisms remain unknown. Potential causes may include hearing loss, dysfunction in the somatosensory system, and auditory cortical dysfunction, although severe underlying pathology is rare. Currently, diagnosis primarily relies on patient self-reported medical history and physician-based clinical assessment due to the lack of objective testing. Various treatment and management options have been proposed, but their effectiveness varies, and there is no universally agreed-upon treatment option.

CONCLUSIONS

Tinnitus is a complex and heterogeneous disease with a high incidence rate and a tendency to increase with age. A holistic perspective is needed to understand the generation, perception, and emotional responses to tinnitus. Diagnosis requires a comprehensive assessment based on medical history and relevant examinations, identification of concurrent psychosomatic comorbidities, and active pursuit of objective diagnostic methods. At the same time, on the basis of existing treatment plans and combining emerging technologies, we will develop new personalized, precise, and combined treatment plans.

Unveiling the Role of Oxidative Stress in Cochlear Hair Cell Death: Prospective Phytochemical Therapeutics against Sensorineural Hearing Loss

Hearing loss represents a multifaceted and pervasive challenge that deeply impacts various aspects of an individual's life, spanning psychological, emotional, social, and economic realms. Understanding the molecular underpinnings that orchestrate hearing loss remains paramount in the quest for effective therapeutic strategies. This review aims to expound upon the physiological, biochemical, and molecular aspects of hearing loss, with a specific focus on its correlation with diabetes. Within this context, phytochemicals have surfaced as prospective contenders in the pursuit of potential adjuvant therapies. These compounds exhibit noteworthy antioxidant and anti-inflammatory properties, which hold the potential to counteract the detrimental effects induced by oxidative stress and inflammation-prominent contributors to hearing impairment. Furthermore, this review offers an up-to-date exploration of the diverse molecular pathways modulated by these compounds. However, the dynamic landscape of their efficacy warrants recognition as an ongoing investigative topic, inherently contingent upon specific experimental models. Ultimately, to ascertain the genuine potential of phytochemicals as agents in hearing loss treatment, a comprehensive grasp of the molecular mechanisms at play, coupled with rigorous clinical investigations, stands as an imperative quest.

Conceptual framework for tinnitus: a cognitive model in practice

Tinnitus is a conscious attended awareness perception of sourceless sound. Widespread theoretical and evidence-based neurofunctional and psychological models have tried to explain tinnitus-related distress considering the influence of psychological and cognitive factors. However, tinnitus models seem to be less focused on causality, thereby easily misleading interpretations. Also, they may be incapable of individualization. This study proposes a Conceptual Cognitive Framework (CCF) providing insight into cognitive mechanisms involved in the predisposition, precipitation, and perpetuation of tinnitus and consequent cognitive-emotional disturbances. The current CCF for tinnitus relies on evaluative conditional learning and appraisal, generating negative valence (emotional value) and arousal (cognitive value) to annoyance, distress, and distorted perception. The suggested methodology is well-defined, reproducible, and accessible, which can help foster future high-quality clinical databases. Perceived tinnitus through the perpetual-learning process can always lead to annoyance, but only in the clinical stage directly cause annoyance. In the clinical stage, tinnitus perception can lead indirectly to distress only with experiencing annoyance either with ("I n d - 1 C " = 1.87; 95% CI 1.18-2.72)["1st indirect path in the Clinical stage model": Tinnitus Loudness → Attention Bias → Cognitive-Emotional Value → Annoyance → Clinical Distress]or without ("I n d - 2 C "= 2.03; 95% CI 1.02-3.32)[ "2nd indirect path in the Clinical stage model": Tinnitus Loudness → Annoyance → Clinical Distress] the perpetual-learning process. Further real-life testing of the CCF is expected to express a meticulous, decision-supporting platform for cognitive rehabilitation and clinical interventions. Furthermore, the suggested methodology offers a reliable platform for CCF development in other cognitive impairments and supports the causal clinical data models. It may also enhance our knowledge of psychological disorders and complicated comorbidities by supporting the design of different rehabilitation interventions and comprehensive frameworks in line with the "preventive medicine" policy.

The association of subjective and objective sleep measures with chronic tinnitus

STUDY OBJECTIVES

Poor sleep is a prevalent complaint in the population with chronic tinnitus, but the relationship between the two is not well-characterized. The objective of this study was to understand how subjective and objective measures of sleep compare in patients with or without chronic tinnitus.

METHODS

This prospective cohort study included consecutive adult patients who presented to a sleep laboratory between January 19, 2017, and January 10, 2020. All patients underwent an in-laboratory nocturnal polysomnogram and filled out questionnaires including the Pittsburgh Sleep Quality Index (PSQI), Tinnitus Screener, and Tinnitus Handicap Inventory, among others.

RESULTS

The study included 1,968 participants, out of which 284 (14.4%) reported chronic tinnitus. Patients with chronic tinnitus were younger (51.6 years vs 54.1 years; P < .05) and more likely female (16.4% vs 11.7%; P < .005). They demonstrated worse subjective sleep quality (PSQI: 11.3 vs 9.5; P < .0005) and increased sleepiness (Epworth Sleepiness Scale: 9.8 vs 8.6; P < .005). In the objective sleep parameters only the total sleep time was increased in chronic tinnitus (311.5 vs 294.5 minutes; P < .05) and total arousals were decreased (41.7 vs 47; P < .005). Sleep stage N3 was higher in those with chronic tinnitus (14.9% vs 13.0%; P < .05). In multivariable analyses, as PSQI increases the odds of chronic tinnitus increases. This effect was modified by age: In those younger than 55 years of age, the odds of the presence of chronic tinnitus was 1.10 (95% confidence interval, 1.03, 1.17) times higher as PSQI increased.

CONCLUSIONS

Chronic tinnitus is associated with significant changes in qualitative sleep (higher PSQI) but no major differences in quantitative sleep measures were observed.

CITATION

Weingarten JA, Islam A, Dubrovsky B, Gharanei M, Coelho DH. The association of subjective and objective sleep measures with chronic tinnitus. J Clin Sleep Med. 2024;20(3):399-405.

What is the role of the hippocampus and parahippocampal gyrus in the persistence of tinnitus?

The hippocampus and parahippocampal gyrus have been implicated as part of a tinnitus network by a number of studies. These structures are usually considered in the context of a "limbic system," a concept typically invoked to explain the emotional response to tinnitus. Despite this common framing, it is not apparent from current literature that this is necessarily the main functional role of these structures in persistent tinnitus. Here, we highlight a different role that encompasses their most commonly implicated functional position within the brain-that is, as a memory system. We consider tinnitus as an auditory object that is held in memory, which may be made persistent by associated activity from the hippocampus and parahippocampal gyrus. Evidence from animal and human studies implicating these structures in tinnitus is reviewed and used as an anchor for this hypothesis. We highlight the potential for the hippocampus/parahippocampal gyrus to facilitate maintenance of the memory of the tinnitus percept via communication with auditory cortex, rather than (or in addition to) mediating emotional responses to this percept.

A Pilot Study to Evaluate a Residual Inhibition Technique in Hearing Aids for Suppression of Tinnitus

Tinnitus acoustic therapy is defined as any use of sound where the intent is to alter the tinnitus perception and/or the reactions to tinnitus in a clinically beneficial way. The parameters of sound that may cause beneficial effects, however, are currently only theorized with limited data supporting their effectiveness. Residual inhibition is the temporary suppression or elimination of tinnitus that is usually observed following appropriate auditory stimulation. Our pilot study investigated the effects of a therapeutic acoustic stimulus that was individually customized to maximize residual inhibition of tinnitus and extend its duration to determine if there could be a sustained suppression of the tinnitus signal (i.e., reduced tinnitus loudness) and a reduction in the psychological and emotional reactions to tinnitus. This pilot study had two objectives: (1) to evaluate the feasibility of residual inhibition technique therapy through daily use of hearing aids and (2) to determine its effects by measuring reactionary changes in tinnitus with the Tinnitus Functional Index (TFI) and perceptual changes in tinnitus loudness. A total of 20 adults (14 males, 6 females; mean age: 58 years, SD = 12.88) with chronic tinnitus were enrolled in a four-visit study that consisted of the following: (1) baseline visit and initiation of the intervention period, (2) a 1-month postintervention visit, (3) 2-month postintervention visit and initiation of a wash-out period, and (4) a 3-month visit to assess the wash-out period and any lasting effects of the intervention. The intervention consisted of fitting bilateral hearing aids and creating an individualized residual inhibition stimulus that was streamed via Bluetooth from a smartphone application to the hearing aids. The participants were instructed to wear the hearing aids and stream the residual inhibition stimulus all waking hours for the 2-month intervention period. During the wash-out period, the participants were instructed to use the hearing aids for amplification, but the residual inhibition stimulus was discontinued. At all visits, the participants completed the TFI, study-specific self-report measures to document perceptions of tinnitus, a psychoacoustic test battery consisting of tinnitus loudness and pitch matching, and a residual inhibition test battery consisting of minimum masking and minimum residual inhibition levels. At the end of the trial, participants were interviewed about the study experience and acceptability of the residual inhibition treatment technique. Repeated measures analyses of variance (ANOVA) were conducted on the two main outcomes (TFI total score and tinnitus loudness) across all four visits. The results showed a significant main effect of visit on the TFI total score ( p  < 0.0001). Specifically, the results indicated a significant reduction in TFI total scores from baseline to the 1-month post-intervention period, which remained stable across the 2-month post-intervention period and the wash-out period. The ANOVA results did not show a significant change in tinnitus loudness as a function of visit ( p  = 0.480). The majority of the participants reported a positive experience with the study intervention at their exit interview. This pilot study demonstrated that residual inhibition as a sound therapy for tinnitus, specifically through the daily use of hearing aids, was feasible and acceptable to individuals suffering from chronic tinnitus. In addition, participants showed improvement in reactions to tinnitus as demonstrated by sustained reduction in TFI scores on average over the course of the treatment period. Achieving residual inhibition may also provide patients a feeling of control over their tinnitus, and this may have a synergistic effect in reducing the psychological and emotional distress associated with tinnitus. There was no significant reduction in long-term tinnitus loudness resulting from the residual inhibition treatment; however, the current pilot study may not have had sufficient power to detect such a change. The combination of tinnitus suppression and improved psychosocial/emotional reactions to tinnitus may result in a better quality of life in both the short and long term. A larger-scale study is needed to determine the validity of using residual inhibition as a clinical therapy option and to ascertain any effects on both perception and reactions to tinnitus.

Focal tDCS of auditory cortex in chronic tinnitus: A randomized controlled mechanistic trial

OBJECTIVE

The goal of this pilot study was to understand how focal transcranial direct current stimulation (tDCS) targeting auditory cortex changes brain function in chronic tinnitus using magnetic resonance imaging (MRI).

METHODS

People with chronic tinnitus were randomized to active or sham tDCS on five consecutive days in this mechanistic trial (n = 10/group). Focal 4x1 tDCS (central anode, surround cathodes) targeted left auditory cortex, with single-blind 2 mA current during twenty-minute sessions. Arterial spin-labeled and blood oxygenation level dependent MRI occurred immediately before and after the first tDCS session, and tinnitus symptoms were measured starting one week before the first tDCS session and through four weeks after the final session.

RESULTS

Acute increases in cerebral blood flow and functional connectivity were noted in auditory cortex after the first active tDCS session. Reduced tinnitus loudness ratings after the final tDCS session correlated with acute change in functional connectivity between an auditory network and mediodorsal thalamus and prefrontal cortex. Reduced tinnitus intrusiveness also correlated with acute change in connectivity between precuneus and an auditory network.

CONCLUSIONS

Focal auditory-cortex tDCS can influence function in thalamus, auditory, and prefrontal cortex, which may associate with improved tinnitus.

SIGNIFICANCE

With future refinement, tDCS targeting auditory cortex could become a viable intervention for tinnitus.

Rehabilitation Service Needs and Preferences among Veterans with Tinnitus: A Qualitative Study

Tinnitus is prevalent among military Veterans, yet there is a gap between the demand and the provision of services for tinnitus rehabilitation services within the Veterans Health Administration (VHA). We sought to understand tinnitus rehabilitation service needs and preferences among Veterans with bothersome tinnitus who use Veterans Affairs (VA) services. We conducted semistructured telephone interviews in 2019 with Veterans diagnosed with tinnitus, who reported it as bothersome. Veterans were purposively sampled to represent national VA users, with and without comorbid traumatic brain injury (TBI), and who were or were not interested in tinnitus rehabilitation services. Qualitative data were analyzed using a modified grounded theory approach. Among 40 Veterans interviewed (32 men, 8 women; 50% with TBI), 72.5% endorsed being somewhat/very likely to be interested in tinnitus rehabilitation services while 27.5% were very/somewhat unlikely. Themes related to Veterans' interest in tinnitus rehabilitation services included barriers and facilitators to participation and preferences for receiving tinnitus services (e.g., individual vs. group-based; in-person vs. remote access). Our findings highlight factors that influence Veterans' reported need and preferences for, and readiness to engage in, rehabilitation services for tinnitus. Personalized or otherwise adaptable approaches to program delivery may help ensure maximal uptake among Veterans.

The Impact of Tinnitus Severity on Work Functioning among U.S. Military Veterans with Tinnitus

Tinnitus is highly prevalent among military Veterans. Severe tinnitus can be associated with negative impacts on daily life. Veterans with severe tinnitus may also have greater difficulties in functional roles, including work. However, few studies have explicitly explored this relationship. Traumatic brain injury (TBI), also prevalent among Veterans, is associated with tinnitus and can additionally impair work functioning. This quantitative investigation used a population-based survey to assess the relationship between tinnitus severity, measured using the Tinnitus Functional Index (TFI), and the impact of tinnitus on work, measured using a composite score from the Tinnitus History Questionnaire, among a stratified random sample of VA healthcare-using Veterans diagnosed with tinnitus, with and without comorbid TBI. Analyses were weighted to account for sampling design and Veteran non-response; multiple imputation was used to account for missing data. Results indicated that for every 1-point increase in TFI score, there was an average 8% increase in the odds of reporting a high level of impact on work functioning (OR: 1.08; 95% CI: 1.06, 1.11). Veterans with a comorbid TBI diagnosis, compared with those without, were more likely to have high tinnitus-related impact on work functioning (OR: 2.69, 95% CI: 1.85, 3.91), but the relationship between tinnitus severity and the impact of tinnitus on work functioning did not differ by TBI status. These data can help researchers and clinicians understand complex symptoms experienced by Veterans with tinnitus, with and without TBI, supporting the improved provision of clinical services to these patients.

Neural response properties predict perceived contents and locations elicited by intracranial electrical stimulation of human auditory cortex

Intracranial electrical stimulation (iES) of auditory cortex can elicit sound experiences with a variety of perceived contents (hallucination or illusion) and locations (contralateral or bilateral side), independent of actual acoustic inputs. However, the neural mechanisms underlying this elicitation heterogeneity remain undiscovered. Here, we collected subjective reports following iES at 3062 intracranial sites in 28 patients (both sexes) and identified 113 auditory cortical sites with iES-elicited sound experiences. We then decomposed the sound-induced intracranial electroencephalogram (iEEG) signals recorded from all 113 sites into time-frequency features. We found that the iES-elicited perceived contents can be predicted by the early high-γ features extracted from sound-induced iEEG. In contrast, the perceived locations elicited by stimulating hallucination sites and illusion sites are determined by the late high-γ and long-lasting α features, respectively. Our study unveils the crucial neural signatures of iES-elicited sound experiences in human and presents a new strategy to hearing restoration for individuals suffering from deafness.

Multimodal assessment of tinnitus using functional near-infrared spectroscopy and psychophysiological measures

OBJECTIVE

To use a multimodal approach to classify individuals with tinnitus from controls, and individuals with mild versus severe tinnitus.

DESIGN

We have previously shown feasibility of a non-invasive imaging technique called functional near-infrared spectroscopy (fNIRS) to detect tinnitus-related changes in cortical activity and classify individuals with tinnitus from controls, as well as individuals with mild versus severe tinnitus. In this study we have used a multimodal approach by recording heart rate, heart rate variability and skin conductance, in addition to fNIRS signals, from individuals with tinnitus and controls.

STUDY SAMPLE

Twenty-seven participants with tinnitus and 21 controls were recruited.

RESULTS

Our findings show, addition of heart rate measures can improve accuracy of classifying tinnitus severity, in particular loudness as rated subjectively. The f1-score, a measure of classification accuracy, increased from 0.73 to 0.86 when using a support vector machine classifier for differentiating low versus high tinnitus loudness.

CONCLUSIONS

Subjective tinnitus is a condition that can only be described by the individual experiencing it, as there are currently no objective measures to determine tinnitus presence and severity, or assess the effectiveness of treatments. Objective measurement of tinnitus is a critical step in developing reliable treatments for this debilitating condition.

Heterogeneous correlate and potential diagnostic biomarker of tinnitus based on nonlinear dynamics of resting-state EEG recordings

Tinnitus is a heterogeneous condition of hearing a rattling sound when there is no auditory stimulus. This rattling sound is associated with abnormal synchronous oscillations in auditory and non-auditory cortical areas. Since tinnitus is a highly heterogeneous condition with no objective detection criteria, it is necessary to search for indicators that can be compared between and within participants for diagnostic purposes. This study introduces heterogeneous though comparable indicators of tinnitus through investigation of spontaneous fluctuations in resting-state brain dynamics. The proposed approach uses nonlinear measures of chaos theory, to detect tinnitus and cross correlation patterns to reflect many of the previously reported neural correlates of tinnitus. These indicators may serve as effective measures of tinnitus risk even at early ages before any symptom is reported. The approach quantifies differences in oscillatory brain dynamics of tinnitus and normal subjects. It demonstrates that the left temporal areas of subjects with tinnitus exhibit larger lyapunov exponent indicating irregularity of brain dynamics in these regions. More complex dynamics is further recognized in tinnitus cases through entropy. We use this evidence to distinguish tinnitus patients from normal participants. Besides, we illustrate that certain anticorrelation patterns appear in these nonlinear measures across temporal and frontal areas in the brain perhaps corresponding to increased/decreased connectivity in certain brain networks and a shift in the balance of excitation and inhibition in tinnitus. Additionally, the main correlations are lost in tinnitus participants compared to control group suggesting involvement of distinct neural mechanisms in generation and persistence of tinnitus.

Usefulness of Yoga in the management of tinnitus during COVID-19: A narrative review

The emergence of Coronavirus disease 2019 (COVID- 19) has resulted in an unprecedented global health crisis. Tinnitus is the most commonly reported symptom when the COVID-19 impacts the auditory-vestibular system. There are a variety of management strategies for amelioration of tinnitus including Yoga. The present review deals with three issues: one, occurrence of tinnitus in persons affected by COVID-19; two, the impact of COVID-19 situation on tinnitus severity; and three, the potential of Yoga as an intervention strategy. Literature search was carried out through search engines like PubMed, Cochrane, Web of Science and Google scholar using keywords like 'tinnitus', 'COVID-19' and 'Yoga'. The relevant studies were identified and the findings summarized in a narrative manner. Based on the evidence obtained in the present review, the authors propose that yoga can be used as an effective strategy in overcoming the psychosocial factors associated with COVID-19 particularly in this pandemic and related lockdown situation. It is also proposed here that teleyoga can serve as a practical, feasible and safe mode for providing therapeutic services for tinnitus-related issues particularly in the present pandemic situation.

The effect of music therapy on tinnitus: A systematic review

OBJECTIVES

Tinnitus is a common otological symptom affecting almost all aspects of life, especially the quality of daily life. The present study aims to analyze music therapy effect on tinnitus patients. This paper mainly analyzes 3 kinds of music therapy: Heidelberg model of music therapy (HMOMT), standard music therapy (SMT), and tailor-made notched music training (TMNMT). To provide a reference for the follow-up treatment of tinnitus, whether to take and what kind of music therapy.

METHOD

A systematic literature search was performed in PubMed, Cochrane Library, EMBASE, Web of Science, and MEDLINE to obtain potential studies from their inception to May 2023 in all languages. Two researchers independently screened the studies, extracted data, and assessed the quality of the included studies. We included all randomized and non-randomized controlled trials that used music therapy to treat patients with tinnitus. We used fixed-effects and random-effect models to analyze data based on the heterogeneity results. The data analysis was performed by using Stata 12.0.

RESULTS

A total of 19 studies with 904 cases were included. Compared with before treatment, music therapy significantly reduces the tinnitus questionnaire score and tinnitus handicap inventory score. HMOMT, SMT, and TMNMT all significantly decrease tinnitus scores. Although the order of effectiveness of the 3 drugs is TMNMT > SMT > HMOMT, there is no statistical significance (P > .5).

CONCLUSION

This meta-analysis of accumulated clinical trial data suggests that music therapy can relieve tinnitus symptoms and loudness. Among music therapies, SMT is recommended first for tinnitus based on cost, efficacy, and convenience. At the same time, TMNMT and HMOMT can be used as alternative therapies for specific cases.

Evidence of cochlear neural degeneration in normal-hearing subjects with tinnitus

Tinnitus, reduced sound-level tolerance, and difficulties hearing in noisy environments are the most common complaints associated with sensorineural hearing loss in adult populations. This study aims to clarify if cochlear neural degeneration estimated in a large pool of participants with normal audiograms is associated with self-report of tinnitus using a test battery probing the different stages of the auditory processing from hair cell responses to the auditory reflexes of the brainstem. Self-report of chronic tinnitus was significantly associated with (1) reduced cochlear nerve responses, (2) weaker middle-ear muscle reflexes, (3) stronger medial olivocochlear efferent reflexes and (4) hyperactivity in the central auditory pathways. These results support the model of tinnitus generation whereby decreased neural activity from a damaged cochlea can elicit hyperactivity from decreased inhibition in the central nervous system.

Neural Plasticity in Tinnitus Mechanisms

Basic work into neuroplasticity mechanisms in both invertebrate and vertebrate brains, followed by the development of the first animal model of tinnitus, and coupled with clinical studies of tinnitus, meant that, by 1990, Jastreboff [...].

Prevalence of tinnitus and hyperacusis in 9-12-year-old children

OBJECTIVES

To estimate the prevalence of tinnitus and hyperacusis in children aged 9-12 years in Flanders, as well as to explore the associations with hearing abilities and listening behaviours.

DESIGN

A cross-sectional survey was undertaken in four different Flemish schools. The questionnaire was distributed among 415 children, with a response rate of 97.3%.

RESULTS

The prevalence of permanent tinnitus was 10.5% and of hyperacusis was 3.3%. The hyperacusis prevalence was higher in girls (p < .05). Some children reported effects of tinnitus in terms of anxiety (20.1%), sleep (36.5%), and concentration (24.8%). When listening to personal listening devices, 33.5% of the children reported to listen for at least 1 h at 60% or higher of the volume range. Moreover, 54.9% of children stated to never wear hearing protection.

CONCLUSIONS

Tinnitus and hyperacusis are prevalent in children aged 9-12 years. Some of these children might be overlooked and, as such, not receiving the required follow-up or counselling. Development of guidelines for the assessment of these auditory symptoms in children would help to determine the prevalence numbers with greater accuracy. Sensibility campaigns for safe listening are warranted, as more than half of the children never use hearing protection.

An MR spectroscopy study of temporal areas excluding primary auditory cortex and frontal regions in subjective bilateral and unilateral tinnitus

Previous studies indicate changes in neurotransmission along the auditory pathway in subjective tinnitus. Most authors, however, investigated brain regions including the primary auditory cortex, whose physiology can be affected by concurrent hearing deficits. In the present MR spectroscopy study we assumed increased levels of glutamate and glutamine (Glx), and other Central Nervous System metabolites in the temporal lobe outside the primary auditory cortex, in a region involved in conscious auditory perception and memory. We studied 52 participants with unilateral (n = 24) and bilateral (n = 28) tinnitus, and a control group without tinnitus (n = 25), all with no severe hearing losses and a similar hearing profile. None of the metabolite levels in the temporal regions of interest were found related to tinnitus status or laterality. Unexpectedly, we found a tendency of increased concentration of Glx in the control left medial frontal region in bilateral vs unilateral tinnitus. Slightly elevated depressive and anxiety symptoms were also shown in participants with tinnitus, as compared to healthy individuals, with the bilateral tinnitus group marginally more affected. We discuss no apparent effect in the temporal lobes, as well as the role of frontal brain areas, with respect to hearing loss, attention and psychological well-being in chronic tinnitus. We furthermore elaborate on the design-related and technical obstacles of MR spectroscopy.

Current and Emerging Therapies for Chronic Subjective Tinnitus

IMPORTANCE

Chronic subjective tinnitus, the perception of sound without an external source for longer than six months, may be a greatly debilitating condition for some people, and is associated with psychiatric comorbidities and high healthcare costs. Current treatments are not beneficial for all patients and there is a large need for new therapies for tinnitus.

OBSERVATIONS

Unlike rarer cases of objective tinnitus, chronic subjective tinnitus often has no obvious etiology and a diverse pathophysiology. In the absence of objective testing, diagnosis is heavily based on clinical assessment. Management strategies include hearing aids, sound masking, tinnitus retraining therapy, cognitive behavioral therapy, and emerging therapies including transcranial magnetic stimulation and electrical stimulation.

CONCLUSIONS AND RELEVANCE

Although current treatments are limited, emerging diagnostics and treatments provide promising avenues for the management of tinnitus symptoms.

Acoustic differences in tinnitus between noise-induced and non-noise-induced hearing loss

BACKGROUND

Tinnitus, the perception of sound without external stimuli, varies across hearing loss types. The present study compared the acoustic characteristics of tinnitus in patients with noise-induced hearing loss (NIHL) and in those with hearing loss unrelated to noise exposure.

OBJECTIVE

This study compared the acoustic characteristics of tinnitus in patients with noise-induced and non-noise-induced hearing loss.

METHODS

A total of 403 patients with tinnitus were divided into those with noise-induced and non-noise-induced hearing loss. Patients were evaluated by pure tone audiometry (PTA), tinnitogram, transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and auditory brainstem evoked response (ABR) tests.

RESULTS

Patients with NIHL exhibited significantly higher hearing thresholds across all frequencies (125-8000 Hz) (p < .05) and reported significantly higher tinnitus intensity (p < .05). Otoacoustic emission tests showed that response rates were significantly lower (p < .05), and ABR tests found that latency periods were significantly more prolonged (p < .05), in patients with NIHL.

CONCLUSIONS

Tinnitus differs acoustically between patients with NIHL and those with non-noise-induced hearing loss, with specific patterns of intensity and auditory responses. These findings emphasize the need for tailoring the management of tinnitus according to the underlying type of hearing loss.

The Effectiveness of a Smartphone Application for Tinnitus Relief

BACKGROUND

There has been a growing interest in the provision of smartphone- or internet-based tinnitus management. Studies have shown a positive impact of the smartphone applications on tinnitus symptoms. However, research into a relatively long-term effect of these applications on tinnitus relief as well as sound preferences has been sparse. This study explored the potential benefit of a tinnitus application in tinnitus relief over a period of six months.

METHODS

Twenty-two participants with subjective tinnitus were enrolled in the study. Puretone audiometry, tinnitus pitch and loudness matching, stress assessment, and questionnaires were completed at the initial visit and three and six months after the first visit. The participants used the tinnitus application for six months.

RESULTS

A significant reduction in subjective tinnitus loudness and annoyance and subjective stress level was observed. The Tinnitus Handicap Inventory scores were also significantly decreased after six months. The participants also reported high satisfaction with the application. Music and environmental sounds were the most preferred sound stimuli.

CONCLUSIONS

The findings of this study demonstrate the potential benefit of the tinnitus application for tinnitus improvement.

The Analogy between Tinnitus and Chronic Pain: A Phenomenological Approach

Tinnitus is an auditory sensation without external acoustic stimulation or significance, which may be lived as an unpleasant experience and impact the subject's quality of life. Tinnitus loudness, which is generally low, bears no relation to distress. Factors other than psychoacoustic (such as psychological factors) are therefore implicated in the way tinnitus is experienced. The aim of this article is to attempt to understand how tinnitus can, like chronic pain, generate a 'crisis' in the process of existence, which may go as far as the collapse of the subject. The main idea put forward in the present article is that tinnitus may be compared to the phenomenon of pain from the point of view of the way it is experienced. Although the analogy between tinnitus and pain has often been made in the literature, it has been limited to a parallel concerning putative physiopathological mechanisms and has never really been explored in depth from the phenomenological point of view. Tinnitus is comparable to pain inasmuch as it is felt, not perceived: it springs up (without intention or exploration), abolishes the distance between the subject and the sensation (there is only a subject and no object), and has nothing to say about the world. Like pain, tinnitus is formless and abnormal and can alter the normal order of the world with maximum intensity. Finally, tinnitus and pain enclose the subject within the limits of the body, which then becomes in excess. Tinnitus may be a source of suffering, which affects not only the body but a person's very existence and, in particular, its deployment in time. Plans are thus abolished, so time is no longer 'secreted', it is enclosed in an eternal present. If the crisis triggered by tinnitus is not resolved, the subject may buckle and collapse (depression) when their resources for resisting are depleted. The path may be long and winding from the moment when tinnitus emerges to when it assaults existence and its eventual integration into a new existential norm where tinnitus is no longer a source of disturbance.

Focal transcranial direct current stimulation of auditory cortex in chronic tinnitus: A randomized controlled mechanistic trial

Objective

The goal of this pilot MRI study was to understand how focal transcranial direct current stimulation (tDCS) targeting auditory cortex changes brain function in chronic tinnitus.

Methods

People with chronic tinnitus were randomized to active or sham tDCS on five consecutive days in this pilot mechanistic trial (n=10/group). Focal 4×1 tDCS (central anode, surround cathodes) targeted left auditory cortex, with single-blind 2mA current during twenty-minute sessions. Arterial spin-labeled and blood oxygenation level dependent MRI occurred immediately before and after the first tDCS session, and tinnitus symptoms were measured starting one week before the first tDCS session and through four weeks after the final session.

Results

Acute increases in cerebral blood flow and functional connectivity were noted in auditory cortex after the first active tDCS session. Reduced tinnitus loudness ratings after the final tDCS session correlated with acute change in functional connectivity between an auditory network and mediodorsal thalamus and prefrontal cortex. Reduced tinnitus intrusiveness also correlated with acute change in connectivity between precuneus and an auditory network.

Conclusions

Focal auditory-cortex tDCS can influence function in thalamus, auditory, and prefrontal cortex, which may associate with improved tinnitus.

Significance

With future refinement, noninvasive brain stimulation targeting auditory cortex could become a viable intervention for tinnitus.

Use of Some Relevant Parameters for Primary Prediction of Brain Activity in Idiopathic Tinnitus Based on a Machine Learning Application

INTRODUCTION

Tinnitus is one of the most common complaints, distressing about 15-24% of the adult population. Because of its pathophysiology heterogeneity, no curable treatment has been attained yet. Even though a neuromodulation management technique based on the tinnitus network model is currently being developed, it has not yet worked because the most involved brain areas still remain unpredictable from the patient's individual clinical and functional profile. A remarkable correlation between tinnitus network activity and the subjective measures of tinnitus like perceived loudness and annoyance and functional handicap is well established. Therefore, this study aimed to develop software for predicting the involved brain areas in the tinnitus network based on the subjective characteristics and clinical profile of patients using a supervised machine-learning method.

METHODS

The involved brain areas of 30 tinnitus patients ranging from 6 to 80 months in duration were recognized by using QEEG and sLORETA software. There was a correlation between subjective information and those areas of activities in all rhythms by which we wrote our software.

RESULTS

For verification and validation of the software, we compared and analyzed the results with SPSS data and the receiver operating characteristic (ROC) curves.

CONCLUSIONS

The findings of this study confirmed the effectiveness of the software in predicting the brain activity in tinnitus subjects; however, some other important parameters can be added to the model to strengthen its reliability and feasibility in clinical use.

Targeting the Limbic System: Insights into Its Involvement in Tinnitus

Tinnitus is originally derived from the Latin verb tinnire, which means "to ring". Tinnitus, a complex disorder, is a result of sentient cognizance of a sound in the absence of an external auditory stimulus. It is reported in children, adults, and older populations. Patients suffering from tinnitus often present with hearing loss, anxiety, depression, and sleep disruption in addition to a hissing and ringing in the ear. Surgical interventions and many other forms of treatment have been only partially effective due to heterogeneity in tinnitus patients and a lack of understanding of the mechanisms of tinnitus. Although researchers across the globe have made significant progress in understanding the underlying mechanisms of tinnitus over the past few decades, tinnitus is still deemed to be a scientific enigma. This review summarises the role of the limbic system in tinnitus development and provides insight into the development of potential target-specific tinnitus therapies.

The clinical effects of modified tinnitus relieving sound (MTRS) for chronic tinnitus: protocol for a randomized controlled trial

INTRODUCTION

Chronic subjective tinnitus has become an increasingly serious hazard that affects the health-related quality of life for millions of people. Due to the lack of curative treatment strategies, this study aims to introduce a novel acoustic therapy named the modified tinnitus relieving sound (MTRS) for tinnitus and to evaluate the efficacy of MTRS in comparison with unmodified music (UM) which served as a control.

METHODS AND ANALYSIS

A randomized, double-blinded, controlled, clinical trial will be carried out. Sixty-eight patients with subjective tinnitus will be recruited and randomly allocated into two groups in 1:1 ratio. The primary outcome is Tinnitus Handicapped Inventory (THI); the secondary outcomes are the Hospital Anxiety and Distress Scale (HADS; HADS subscales for Anxiety (HADS-A) and Depression (HADS-D)), Athens Insomnia Scale (AIS), the visual analog scale (VAS) for tinnitus, and tinnitus loudness matched by sensation level (SL). Assessment will be performed at baseline and at 1, 3, 9, and 12 months post-randomization. The sound stimulus will be persistent until 9 months after randomization, and be interdictory in the last three months. Data collected during the intervention process will be analyzed and compared to baseline.

ETHICS AND DISSEMINATION

This trial received ethical approval from the Institutional Review Board (IRB) of Eye & ENT Hospital of Fudan University (No. 2017048). The study results will be disseminated via academic journals and conferences.

FUNDING

This study is supported by the Shanghai Shenkang Development Program (SHDC12019119), the Excellent Doctors-Excellent Clinical Researchers Program (SYB202008), the Shanghai Rising-Star Program (23QC1401200), the Shanghai Rising Stars of Medical Talent Youth Development Program (2021-99), the National Natural Science Foundation of China (81800912), and the National Natural Science Foundation of Shanghai (21ZR1411800).

TRIAL REGISTRATION

ClinicalTrials.gov NCT04026932. Registered on 18 July 2019.

Hearing Aids Combined With Educational Counseling Versus Educational Counseling Alone for Tinnitus Treatment in Patients With Hearing Loss: A Longitudinal Follow-Up Study

PURPOSE

The effect of hearing aids (HAs) and educational counseling (EC) or their combination on tinnitus is ambiguous. This study aimed to investigate whether the combined use of HAs and EC is more effective than EC alone on tinnitus relief.

METHOD

A total of 72 adults with chronic, bothersome tinnitus and coexisting sensorineural hearing loss completed at least 1-month and 3-month follow-up. After receiving EC and HA prescriptions, 21 participants selected to purchase HAs (i.e., the HA + EC group), whereas the remaining 51 refused to use HAs despite recommendations (i.e., the EC group). Tinnitus severity was measured by Tinnitus Handicap Inventory (THI), Tinnitus Evaluation Questionnaire (TEQ), and Visual Analog Scale (VAS) for loudness. The primary outcome measure was THI, and tinnitus relief was defined as a 20-point or more reduction in THI. A generalized linear mixed model was used to confirm that the heterogeneity in baseline characteristics between groups did not interfere with the results.

RESULTS

The THI, TEQ, and VAS scores decreased significantly after treatments, and both groups yielded a similar trend of reduction. There were no significant differences in the incidence of tinnitus relief and time-to-event curves between the two groups. In addition, the length of follow-up did not affect treatment effectiveness.

CONCLUSION

There was insufficient evidence to support the superiority of the combined use of HA and EC for tinnitus over EC with no device.

Down-Regulation of Tinnitus Negative Valence via Concurrent HD-tDCS and PEI Technique: A Pilot Study

Around 30% of the general population experience subjective tinnitus, characterized by conscious attended awareness perception of sound without an external source. Clinical distress tinnitus is more than just experiencing a phantom sound, as it can be highly disruptive and debilitating, leading those affected to seek clinical help. Effective tinnitus treatments are crucial for psychological well-being, but our limited understanding of the underlying neural mechanisms and a lack of a universal cure necessitate further treatment development. In light of the neurofunctional tinnitus model predictions and transcranial electrical stimulation, we conducted an open-label, single-arm, pilot study that utilized high-definition transcranial direct current stimulation (HD-tDCS) concurrent with positive emotion induction (PEI) techniques for ten consecutive sessions to down-regulate tinnitus negative valence in patients with clinical distress tinnitus. We acquired resting-state functional magnetic resonance imaging scans of 12 tinnitus patients (7 females, mean age = 51.25 ± 12.90 years) before and after the intervention to examine resting-state functional connectivity (rsFC) alterations in specific seed regions. The results showed reduced rsFC at post-intervention between the attention and emotion processing regions as follows: (1) bilateral amygdala and left superior parietal lobule (SPL), (2) left amygdala and right SPL, (3) bilateral dorsolateral prefrontal cortex (dlPFC) and bilateral pregenual anterior cingulate cortex (pgACC), and (4) left dlPFC and bilateral pgACC (FWE corrected p < 0.05). Furthermore, the post-intervention tinnitus handicap inventory scores were significantly lower than the pre-intervention scores (p < 0.05). We concluded that concurrent HD-tDCS and PEI might be effective in reducing tinnitus negative valence, thus alleviating tinnitus distress.

Comparative analysis of acoustic therapies for tinnitus treatment based on auditory event-related potentials

Introduction

So far, Auditory Event-Related Potential (AERP) features have been used to characterize neural activity of patients with tinnitus. However, these EEG patterns could be used to evaluate tinnitus evolution as well. The aim of the present study is to propose a methodology based on AERPs to evaluate the effectiveness of four acoustic therapies for tinnitus treatment.

Methods

The acoustic therapies were: (1) Tinnitus Retraining Therapy (TRT), (2) Auditory Discrimination Therapy (ADT), (3) Therapy for Enriched Acoustic Environment (TEAE), and (4) Binaural Beats Therapy (BBT). In addition, relaxing music was included as a placebo for both: tinnitus sufferers and healthy individuals. To meet this aim, 103 participants were recruited, 53% were females and 47% were males. All the participants were treated for 8 weeks with one of these five sounds, which were moreover tuned in accordance with the acoustic features of their tinnitus (if applied) and hearing loss. They were electroencephalographically monitored before and after their acoustic therapy, and wherefrom AERPs were estimated. The sound effect of acoustic therapies was evaluated by examining the area under the curve of those AERPs. Two parameters were obtained: (1) amplitude and (2) topographical distribution.

Results

The findings of the investigation showed that after an 8-week treatment, TRT and ADT, respectively achieved significant neurophysiological changes over somatosensory and occipital regions. On one hand, TRT increased the tinnitus perception. On the other hand, ADT redirected the tinnitus attention, what in turn diminished the tinnitus perception. Tinnitus handicapped inventory outcomes verified these neurophysiological findings, revealing that 31% of patients in each group reported that TRT increased tinnitus perception, but ADT diminished it.

Discussion

Tinnitus has been identified as a multifactorial condition highly associated with hearing loss, age, sex, marital status, education, and even, employment. However, no conclusive evidence has been found yet. In this study, a significant (but low) correlation was found between tinnitus intensity and right ear hearing loss, left ear hearing loss, heart rate, area under the curve of AERPs, and acoustic therapy. This study raises the possibility to assign acoustic therapies by neurophysiological response of patient.

Understanding misophonia from an audiological perspective: a systematic review

PURPOSE

Misophonia is a neurophysiological disorder in which certain sounds trigger an intensely emotional or physiological response caused by an increased autonomic nervous system reaction to the triggers. Misophonia is a relatively new condition, and the neurophysiological mechanism behind this condition is not known yet. The assessment and management of misophonia need a team approach. Audiologists are vital members of the team. However, their roles in this condition are not well-understood. The study aims to review the neurophysiological mechanism of misophonia, highlighting the mechanism involved in the audiological pathway and directing the discussion toward applications of findings in the assessment and management of misophonia from the audiological perspective.

METHODS

We reviewed 12 articles from different databases to understand the neurophysiological mechanisms of misophonia. Most of the studies selected were experimental designs involving individuals with misophonia.

RESULTS

The result of the review revealed abnormal activation and connection among the different higher cortical structures in participants with misophonia. By signifying various neurophysiological and neuroradiological findings, the review confirms that misophonia is a neurophysiological disorder that may border between audiology, neurology, and psychiatry. Assessment of study quality reported an overall low risk of bias.

CONCLUSIONS

This review highlights the need to include an audiologist as a team member in the evaluation and management of misophonia.

Comparative Transcriptomic Analysis of Archival Human Vestibular Schwannoma Tissue from Patients with and without Tinnitus

Vestibular schwannoma (VS) is an intracranial tumor that commonly presents with tinnitus and hearing loss. To uncover the molecular mechanisms underlying VS-associated tinnitus, we applied next-generation sequencing (Illumina HiSeq) to formalin-fixed paraffin-embedded archival VS samples from nine patients with tinnitus (VS-Tin) and seven patients without tinnitus (VS-NoTin). Bioinformatic analysis was used to detect differentially expressed genes (DEG; i.e., ≥two-fold change [FC]) while correcting for multiple comparisons. Using RNA-seq analysis, VS-Tin had significantly lower expression of GFAP (logFC = −3.04), APLNR (logFC = −2.95), PREX2 (logFC = −1.44), and PLVAP (logFC = −1.04; all p < 0.01) vs. VS-NoTin. These trends were validated by using real-time RT-qPCR. At the protein level, immunohistochemistry revealed a trend for less PREX2 and apelin expression and greater expression of NLRP3 inflammasome and CD68-positive macrophages in VS-Tin than in VS-NoTin, suggesting the activation of inflammatory processes in VS-Tin. Functional enrichment analysis revealed that the top three protein categories—glycoproteins, signal peptides, and secreted proteins—were significantly enriched in VS-Tin in comparison with VS-NoTin. In a gene set enrichment analysis, the top pathway was allograft rejection, an inflammatory pathway that includes the MMP9, CXCL9, IL16, PF4, ITK, and ACVR2A genes. Future studies are needed to examine the importance of these candidates and of inflammation in VS-associated tinnitus.

Effect of Tinnitus Retraining Therapy in Normal Hearing Individual with Subjective Tinnitus: An Observational Study

This study was done to study the effect of Tinnitus Retraining Therapy (TRT) in Bilateral Normal Hearing Individual with subjective tinnitus and to evaluate the success of simplified TRT with relation to duration of tinnitus, the patient's age and state of mind. As on date there is no definite cure available for tinnitus, so current TRT focuses on reducing the impact of tinnitus on the patient's quality of life. This study included total fifty (50) participants with bilateral normal hearing sensitivity, who had reported to the department of ENT with a complaint of tinnitus in one or both ears. All the participants are active serving military personnel and their dependents of Indian Armed Forces. All the participants had undergone basic audiological test batteries to assess the hearing acuity followed by TRT and its components (TRT counselling and sound therapy) in randomized manner. Audiological test batteries include pure tone audiometry to make sure that the participants have normal hearing acuity in both the ears and then tinnitus matching i.e. pitch and loudness match and measurement of Uncomfortable Level (UCL) followed by sound therapy and counselling. There was significant improvement reported in impact of tinnitus after completion of six (06) months of TRT schedule. Amongst the participants, 40% reported with complete relief from tinnitus, 30% reported with remarkable benefit but they can still perceive the tinnitus, 20% reported with no benefit with TRT and rest of the 10% were not able to tell whether they have got any benefit or not. Normal hearing individual with tinnitus can be benefitted with TRT accompanied with counselling and the improvement in impact of tinnitus severity that ensued over six months of TRT appear to be vigorous with significant clinical outcomes.

Tinnitus Prevalence in the Adult Population-Results from the Gutenberg Health Study

Background and Objectives: Tinnitus is a common symptom in medical practice, although data on its prevalence vary. As the underlying pathophysiological mechanism is still not fully understood, hearing loss is thought to be an important risk factor for the occurrence of tinnitus. The aim of this study was to assess tinnitus prevalence in a large German cohort and to determine its dependence on hearing impairment. Materials and Methods: The Gutenberg Health Study (GHS) is a population-based cohort study and representative for the population of Mainz and its district. Participants were asked whether they suffer from tinnitus and how much they are burdened by it. Extensive audiological examinations using bone- and air-conduction were also performed. Results: 4942 participants (mean age: 61.0, 2550 men and 2392 women) were included in the study. The overall prevalence of tinnitus was 26.1%. Men were affected significantly more often than women. The prevalence of tinnitus increased with age, peaking at ages 75 to 79 years. Considering only annoying tinnitus, the prevalence was 9.8%. Logistic regression showed that participants with severe to complete hearing loss (>65 dB) were more likely to have tinnitus. Conclusions: Tinnitus is a common symptom, and given demographic changes, its prevalence is expected to increase.

Tinnitus-frequency specific activity and connectivity: A MEG study

Tinnitus pathophysiology has been associated with an atypical cortical network that involves functional changes in auditory and non-auditory areas. Numerous resting-state studies have replicated a tinnitus brain network to be significantly different from healthy-controls. Yet it is still unknown whether the cortical reorganization is attributed to the tinnitus frequency specifically or if it is frequency-irrelevant. Employing magnetoencephalography (MEG), the current study aimed to identify frequency-specific activity patterns by using an individual tinnitus tone (TT) and a 500 Hz-control tone (CT) as auditory stimuli, across 54 tinnitus patients. MEG data were analyzed in a data-driven approach employing a whole-head model in source space and in sources' functional connectivity. Compared to the CT, the event related source space analysis revealed a statistically significant response to TT involving fronto-parietal regions. The CT mainly involved typical auditory activation-related regions. A comparison of the cortical responses to a healthy control group that underwent the same paradigm rejected the alternative interpretation that the frequency-specific activation differences were due to the higher frequency of the TT. Overall, the results suggest frequency-specificity of tinnitus-related cortical patterns. In line with previous studies, we demonstrated a tinnitus-frequency specific network comprising left fronto-temporal, fronto-parietal and tempo-parietal junctions.

Tinnitus and treatment-resistant depression

Tinnitus, a frequent disorder, is the conscious perception of a sound in the absence of a corresponding external acoustic sound source in the sense of a phantom sound. Although the majority of people who perceive a tinnitus sound can cope with it and are only minimaly impaired in their quality of lfe, 2-3% of the population perceive tinnitus as a major problem. Recently it has been proposed that the two groups should be differentiated by distict terms: "Tinnitus" describes the auditory or sensory component, whereas "Tinnitus Disorder" reflects the auditory component and the associated suffering. There is overwhelming evidence that a high tinnitus burden is associated with the increased occurrence of comorbidities, including depression. Since no causal therapeutic options are available for patients with tinnitus at the present time, the identification and adequate treatment of relevant comorbidities is of great importance for the reduction of tinnitus distress. This chapter deals with the relationship between tinnitus and depression. The neuronal mechanisms underlying tinnitus will first be discussed. There will also be an overview about depression and treatment resistant depression (TRD). A comprehensive review about the state-of-the-art evidences of the relationship between tinnitus and TRD will then be provided.

Clinical characteristics and psychoacoustic analysis of acute and chronic subjective tinnitus

Objective

This study aimed to understand the demographics, clinical characteristics, and psychoacoustic status of subjective tinnitus patients to explore the factors associated with acute and chronic tinnitus in the general hospitals of Shanghai.

Methods

A cross-sectional study was conducted to investigate the clinical characteristics and psychoacoustic status of subjective tinnitus patients with history greater than 1 month. Data were collected during January 2021 and January 2022 from eight general hospitals in five districts of Shanghai, China. All patients accepted questionnaires and acoustic examination, then SPSS 22.0 and GraphPad Prism 8.0.2 were applied for data analysis.

Results

Among the 359 tinnitus patients, 126 cases were diagnosed with acute tinnitus, 58 cases were subacute tinnitus, and 175 cases were chronic tinnitus. Patients with acute and chronic tinnitus differed in terms of side of tinnitus, hearing loss, frequency of tinnitus, severity of tinnitus, anxiety, depression, and sleep status. Different characteristics were included in the multivariate ordinal logistic regression analysis. Persistent tinnitus (OR = 2.00, p = .008), high frequency hearing loss (OR = 4.77, p < .001), depression (OR = 1.23, p < .001) were found to be positively associated with the course of tinnitus. Unilateral tinnitus (OR = 0.48, p = .003), mild (OR = 0.29, p = .001) and moderate (OR = 0.46, p = .038) hearing loss, VAS scores (OR = 0.82, p = .032), anxiety (OR = 0.81, p < .001), THI scores (OR = 0.98, p = .002), and sleep disorders (OR = 0.94, p = .025) were found to be negatively associated with the course of tinnitus.

Conclusion

Patients with acute tinnitus were at greater risk for anxiety, sleep disturbances, and exacerbation of tinnitus perception, and those with chronic tinnitus were at greater risk for depression.

Lay Summary

Our study demonstrated that patients with acute tinnitus were at greater risk for anxiety, sleep disturbances, and exacerbation of tinnitus perception, and those with chronic tinnitus were at greater risk for depression.

Anxiety, Depression, and Symptom Severity in Patients with Pulsatile and Non-Pulsatile Tinnitus

OBJECTIVE(S)

To compare the rates of anxiety and depression between patients with pulsatile (PT) and non-pulsatile tinnitus (NPT), and their correlation with tinnitus severity.

METHODS

A prospective cross-sectional study of consecutive patients presenting either to the otolaryngology clinic for pulsatile (PT) and NPT or to a tertiary care tinnitus habituation program (THP) were administered the tinnitus handicap inventory (THI), 7-item general anxiety disorder scale (GAD-7), and 9-item patient health questionnaire (PHQ-9). Median scores between groups and correlation of scores within groups were calculated and compared.

RESULTS

Median THI scores were significantly higher for THP and PT patients as compared with unselected NPT patients (58 and 44 vs. 20, p ≤ 0.001). Median GAD-7 (10 vs. 2.5 and 2, p ≤ 0.001) and PHQ-9 (7 vs. 4 and 4, p = 0.04) scores were highest in THP patients compared with PT and NPT. The strongest correlation between tinnitus handicap and psychiatric measures was seen in THP patients.

CONCLUSION

THP patients report higher levels of anxiety and depression compared with PT and other NPT patients. Tinnitus severity correlates more strongly with GAD-7 and PHQ-9 scores in THP patients compared with other patient groups. PT patients have a greater self-perceived tinnitus handicap than the general cohort of NPT patients, statistically comparable to THP patients. Despite this, anxiety and depression are not more severe in patients with PT as they are in THP patients.

LEVEL OF EVIDENCE

2B Laryngoscope, 133:683-688, 2023.

Cannabis use amongst tinnitus patients: consumption patterns and attitudes

BACKGROUND

Tinnitus has a significant impact on quality of life and causes considerable psychological distress. Cannabis is known to modulate neuron hyperexcitability, provide protection against auditory damage, and has been used for treatment for many diseases which have physiological similarities with tinnitus. The objective of this study was to survey patients presenting with tinnitus regarding their perspectives and usage patterns of cannabis.

METHODS

Patients with a primary presenting complaint of tinnitus in a tertiary neuro-otology clinic completed a 18-item questionnaire assessing perception, attitudes, and cannabis usage patterns.

RESULTS

Forty five patients completed the survey (mean age: 54.5 years, 31 females and 14 males). Overall, 96% of patients reported that they would consider cannabis as treatment for their tinnitus. Patients considered cannabis use for auditory symptoms (91%), and symptoms related to their tinnitus, such as emotional complaints (60%), sleep disturbances (64%), and functional disturbances (56%). 36% of patients had previously used cannabis and 22% of patients reported cannabis use at the time of the study. 80% of patients that were actively using cannabis reported that it helped with tinnitus-related symptoms, such as dizziness, anxiety, bodily pain, and sleep disturbances. Most patients would prefer to use edibles (62%), tablet (58%) and cream (47%) formulations of cannabis. Patients were concerned about the cost (29%), potential physical health implications (53%) and psychosocial side effects (60%) of cannabis. Over half of patients learned about cannabis from a friend or family member and only 22% of patients learned about cannabis from a physician or nurse.

CONCLUSION

Cannabis use is common amongst patients with tinnitus and current users of cannabis reported that it helped with their symptoms. Most patients would consider its use as a potential treatment to alleviate their tinnitus-related symptoms and are interested in learning more regarding its use. By understanding how cannabis is perceived by tinnitus patients, healthcare providers can provide appropriate patient education.

Multi-tasking deep network for tinnitus classification and severity prediction from multimodal structural MR images

Objective:Subjective tinnitus is an auditory phantom perceptual disorder without an objective biomarker. Fast and efficient diagnostic tools will advance clinical practice by detecting or confirming the condition, tracking change in severity, and monitoring treatment response. Motivated by evidence of subtle anatomical, morphological, or functional information in magnetic resonance images of the brain, we examine data-driven machine learning methods for joint tinnitus classification (tinnitus or no tinnitus) and tinnitus severity prediction.Approach:We propose a deep multi-task multimodal framework for tinnitus classification and severity prediction using structural MRI (sMRI) data. To leverage complementary information multimodal neuroimaging data, we integrate two modalities of three-dimensional sMRI-T1 weighted (T1w) and T2 weighted (T2w) images. To explore the key components in the MR images that drove task performance, we segment both T1w and T2w images into three different components-cerebrospinal fluid, grey matter and white matter, and evaluate performance of each segmented image.Main results:Results demonstrate that our multimodal framework capitalizes on the information across both modalities (T1w and T2w) for the joint task of tinnitus classification and severity prediction.Significance:Our model outperforms existing learning-based and conventional methods in terms of accuracy, sensitivity, specificity, and negative predictive value.

Tinnitus Prevalence and Associated Factors among Dental Clinicians in the United Arab Emirates

Dental clinicians are at increased risk for developing tinnitus due to exposure to high levels of occupational noise. This study aimed to determine tinnitus prevalence and associated factors among dental clinicians. Interviews were conducted with 150 randomly selected dental clinicians using a questionnaire. Noise levels were measured at three points of time at the operating area. Tinnitus was reported in 19.33% of the participants. The average noise level was significantly higher among participants with tinnitus compared to those without the condition. More participants complained of intermittent tinnitus and the rest had the constant type, with the latter being significantly more bothersome. The weekly average time of using high-speed handpieces, suction and electric handpieces, age and experience had a significant effect on the presence of tinnitus. Only 2.7% of the participants reported the use of a hearing protection device. Tinnitus is a common finding among dental clinicians especially those with higher levels of occupational noise and more frequent use of noise-generating equipment. Knowledge of tinnitus prevalence aids in realizing the extent of its impact and making informed decisions. These results call for improved awareness of the negative impact of clinically-generated noise and emphasize the importance of preventive measures and periodic audiometry exams.