Tinnitus impairs cognitive efficiency

Glymphatic system dysfunction associated with cognitive impairment in chronic tinnitus patients

Background

The glymphatic system has been regarded as a pivotal factor in the pathogenesis of neurodegenerative diseases. Given the heightened risk of cognitive impairment in chronic tinnitus patients, the possible alterations of the glymphatic system in tinnitus patients remain elusive. This study was designed to evaluate glymphatic dysfunction in chronic tinnitus patients using the diffusion tensor imaging (DTI) along the perivascular space (DTI-ALPS) approach.

Methods

Fifty chronic tinnitus patients and 50 age, sex, and education-matched healthy controls (HCs) with normal hearing thresholds were recruited. The DTI-ALPS was calculated from each group. We investigated the differences in the DTI-ALPS index between the tinnitus patients and HCs. The relationships between the DTI-ALPS index and specific cognitive performance were further assessed.

Results

There were significant differences in the DTI-ALPS index between the two groups. The DTI-ALPS index was significantly lower in the tinnitus group than in HCs group (p < 0.01). In addition, the Dyyproj index was significantly higher in the tinnitus group than in the HC group (p < 0.01). In chronic tinnitus patients, the decreased DTI-ALPS index was negatively associated with worse TMT-B scores (r = -0.309, p = 0.039). Moreover, the increased Dyyproj index was negatively correlated with the reduced AVLT performances (r = -0.413, p = 0.005).

Conclusion

In this current study, glymphatic system activity in chronic tinnitus was investigated for the first time using DTI-ALPS index. Significant decrease in glymphatic system function was detected in chronic tinnitus, which correlated well with the specific cognitive performance. The current study may provide pivotal imaging markers for chronic tinnitus with cognitive impairment.

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.

Investigation of the behavior of tinnitus patients under varying listening conditions with simultaneous electroencephalography and pupillometry

OBJECTIVE

This study aims to control all hearing thresholds, including extended high frequencies (EHFs), presents stimuli of varying difficulty levels, and measures electroencephalography (EEG) and pupillometry responses to determine whether listening difficulty in tinnitus patients is effort or fatigue-related.

METHODS

Twenty-one chronic tinnitus patients and 26 matched healthy controls having normal pure-tone averages with symmetrical hearing thresholds were included. Subjects were evaluated with 0.125-20 kHz pure-tone audiometry, Montreal Cognitive Assessment Test (MoCA), Tinnitus Handicap Inventory (THI), EEG, and pupillometry.

RESULTS

Pupil dilatation and EEG alpha power during the "encoding" phase of the presented sentence in tinnitus patients were less in all listening conditions (p < .05). Also, there was no statistically significant relationship between EEG and pupillometry components for all listening conditions and THI or MoCA (p > .05).

CONCLUSION

EEG and pupillometry results under various listening conditions indicate potential listening effort in tinnitus patients even if all frequencies, including EHFs, are controlled. Also, we suggest that pupillometry should be interpreted with caution in autonomic nervous system-related conditions such as tinnitus.

Attention-Modulated Cortical Responses as a Biomarker for Tinnitus

Attention plays an important role in not only the awareness and perception of tinnitus but also its interactions with external sounds. Recent evidence suggests that attention is heightened in the tinnitus brain, likely as a result of relatively local cortical changes specific to deafferentation sites or global changes that help maintain normal cognitive capabilities in individuals with hearing loss. However, most electrophysiological studies have used passive listening paradigms to probe the tinnitus brain and produced mixed results in terms of finding a distinctive biomarker for tinnitus. Here, we designed a selective attention task, in which human adults attended to one of two interleaved tonal (500 Hz and 5 kHz) sequences. In total, 16 tinnitus (5 females) and 13 age- and hearing-matched control (8 females) subjects participated in the study, with the tinnitus subjects matching the tinnitus pitch to 5.4 kHz (range = 1.9-10.8 kHz). Cortical responses were recorded in both passive and attentive listening conditions, producing no differences in P1, N1, and P2 between the tinnitus and control subjects under any conditions. However, a different pattern of results emerged when the difference was examined between the attended and unattended responses. This attention-modulated cortical response was significantly greater in the tinnitus than control subjects: 3.9-times greater for N1 at 5 kHz (95% CI: 2.9 to 5.0, p = 0.007, ηp2 = 0.24) and 3.0 for P2 at 500 Hz (95% CI: 1.9 to 4.5, p = 0.026, ηp2 = 0.17). We interpreted the greater N1 modulation as local neural changes specific to the tinnitus frequency and the greater P2 as global changes to hearing loss. These two cortical measures were used to differentiate between the tinnitus and control subjects, producing 83.3% sensitivity and 76.9% specificity (AUC = 0.81, p = 0.006). These results suggest that the tinnitus brain is more plastic than that of the matched non-tinnitus controls and that the attention-modulated cortical response can be developed as a clinically meaningful biomarker for tinnitus.

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.

Tinnitus-associated cognitive and psychological impairments: a comprehensive review meta-analysis

Background

Tinnitus is strongly associated with an increased risk of cognitive disabilities. The findings of this research will provide valuable support for future investigations aimed at determining the correlation between tinnitus and the risk of cognitive impairments.

Objectives

We investigated the potential correlation between tinnitus and the risk of various cognitive impairments, such as dementia, compromised learning attention, anxiety, depression, and insomnia. The study examined this relationship collectively and by categorizing the data based on different age groups.

Methods

We compiled data from case-control studies and cohort studies obtained from reputable databases such as PubMed, Cochrane Library, and Embase. To minimize potential bias, two reviewers independently assessed the selected articles. After extracting the data, we calculated the pooled odds ratios (ORs) using a random-effects model.

Results

Seventeen relevant studies, comprising an adult population, were included in this analysis. Pooled estimated outcomes revealed a strong association between tinnitus and an elevated risk of dementia-compromised learning, auditory attention, anxiety, depression, and poor sleep quality (P<0.05). Furthermore, the pooled analysis stratified by age demonstrated that patients aged above 60 years, in comparison to those aged 18 to 60 years, exhibited more significant outcomes in relation to the progression of cognitive impairments.

Conclusion

Tinnitus has the potential to increase the risk of cognitive impairments. Moreover, geriatric patients aged above 60 shows a higher susceptibility to developing cognitive disabilities compared to their younger counterparts.

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.

Desensitizing nicotinic agents normalize tinnitus-related inhibitory dysfunction in the auditory cortex and ameliorate behavioral evidence of tinnitus

Tinnitus impacts between 10-20% of the population. Individuals most troubled by their tinnitus have their attention bound to and are distracted by, their tinnitus percept. While numerous treatments to ameliorate tinnitus have been tried, no therapeutic approach has been clinically accepted. The present study used an established condition-suppression noise-exposure rat model of tinnitus to: (1) examine tinnitus-related changes in nAChR function of layer 5 pyramidal (PNs) and of vasoactive intestinal peptide (VIP) neurons in primary auditory cortex (A1) and (2) examine how the partial desensitizing nAChR agonists, sazetidine-A and varenicline, can act as potential therapeutic agents in the treatment of tinnitus. We posited that tinnitus-related changes in layer 5 nAChR responses may underpin the decline in attentional resources previously observed in this animal model (Brozoski et al., 2019). In vitro whole-cell patch-clamp studies previously revealed a significant tinnitus-related loss in nAChR-evoked excitatory postsynaptic currents from A1 layer 5 PNs. In contrast, VIP neurons from animals with behavioral evidence of tinnitus showed significantly increased nAChR-evoked excitability. Here we hypothesize that sazetidine-A and varenicline have therapeutic benefits for subjects who cannot divert their attention away from the phantom sound in their heads. We found that sazetidine-A or varenicline normalized tinnitus-related reductions in GABAergic input currents onto A1 layer 5 PNs. We then tested sazetidine-A and varenicline for the management of tinnitus using our tinnitus animal model. Subcutaneous injection of sazetidine-A or varenicline, 1 h prior to tinnitus testing, significantly decreased the rat's behavioral evidence of tinnitus in a dose-dependent manner. Collectively, these results support the need for additional clinical investigations of partial desensitizing nAChR agonists sazetidine-A and varenicline for the treatment of tinnitus.

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.

Study on tinnitus-related electroencephalogram microstates in patients with vestibular schwannomas

Tinnitus is closely associated with cognition functioning. In order to clarify the central reorganization of tinnitus in patients with vestibular schwannoma (VS), this study explored the aberrant dynamics of electroencephalogram (EEG) microstates and their correlations with tinnitus features in VS patients. Clinical and EEG data were collected from 98 VS patients, including 76 with tinnitus and 22 without tinnitus. Microstates were clustered into four categories. Our EEG microstate analysis revealed that VS patients with tinnitus exhibited an increased frequency of microstate C compared to those without tinnitus. Furthermore, correlation analysis demonstrated that the Tinnitus Handicap Inventory (THI) score was negatively associated with the duration of microstate A and positively associated with the frequency of microstate C. These findings suggest that the time series and syntax characteristics of EEG microstates differ significantly between VS patients with and without tinnitus, potentially reflecting abnormal allocation of neural resources and transition of functional brain activity. Our results provide a foundation for developing diverse treatments for tinnitus in VS patients.

Deep learning-based electroencephalic diagnosis of tinnitus symptom

Tinnitus is a neuropathological phenomenon caused by the recognition of external sound that does not actually exist. Existing diagnostic methods for tinnitus are rather subjective and complicated medical examination procedures. The present study aimed to diagnose tinnitus using deep learning analysis of electroencephalographic (EEG) signals while patients performed auditory cognitive tasks. We found that, during an active oddball task, patients with tinnitus could be identified with an area under the curve of 0.886 through a deep learning model (EEGNet) using EEG signals. Furthermore, using broadband (0.5 to 50 Hz) EEG signals, an analysis of the EEGNet convolutional kernel feature maps revealed that alpha activity might play a crucial role in identifying patients with tinnitus. A subsequent time-frequency analysis of the EEG signals indicated that the tinnitus group had significantly reduced pre-stimulus alpha activity compared with the healthy group. These differences were observed in both the active and passive oddball tasks. Only the target stimuli during the active oddball task yielded significantly higher evoked theta activity in the healthy group compared with the tinnitus group. Our findings suggest that task-relevant EEG features can be considered as a neural signature of tinnitus symptoms and support the feasibility of EEG-based deep-learning approach for the diagnosis of tinnitus.

A Study to Grade the Severity of Tinnitus and its Psychological Impact Using Tinnitus Functional Index (tfi)

Background

Chronic tinnitus has a lot impact on the quality of life of person by affecting his/ her physical health, occupational health and social relations. It can lead to sleep interference, cognitive difficulties, lack of concentration, anxiety, frustration, anger and depression. The present study showed the severity and impact of tinnitus on quality of life of subjects with or without hearing loss using tinnitus functional index (TFI).

Methods

Subjects with history of tinnitus with or without hearing loss including informed consent, otoscopy, pure tone audiometry (PTA) were done. Grading of tinnitus was done by using tinnitus functional index score.

Results

The mean age of participants were 50.20 ± 4.2 years and male to female ratio were found to be 1.05:1. On PTA, 122 participants had hearing loss and 28 had no hearing loss. 49 patients had mild TFI score, 85 had moderate TFI score and 16 had severe hearing loss. The difference in the severity of tinnitus using TFI between normal hearing and sensorineural hearing loss individual was statistically significant. On the other hand, the severity of tinnitus and degree of hearing loss were also found to be statistically significant with p value < 0.0001 chi. Sq = 77.39. This shows that with increase in increase in hearing loss there is increase in TFI sore.

Conclusion

Tinnitus has a negative impact on the quality of life like pshycological, emotional and physical effects. The effects of tinnitus is more in those with co-existing hearing loss.

The Effects of Tinnitus in Probabilistic Learning Tasks: Protocol for an Ecological Momentary Assessment Study

BACKGROUND

Chronic tinnitus is an increasing worldwide health concern, causing a significant burden to the health care system each year. The COVID-19 pandemic has seen a further increase in reported cases. For people with tinnitus, symptoms are exacerbated because of social isolation and the elevated levels of anxiety and depression caused by quarantines and lockdowns. Although it has been reported that patients with tinnitus can experience changes in cognitive capabilities, changes in adaptive learning via decision-making tasks for people with tinnitus have not yet been investigated.

OBJECTIVE

In this study, we aim to assess state- and trait-related impairments in adaptive learning ability on probabilistic learning tasks among people with tinnitus. Given that performance in such tasks can be quantified through computational modeling methods using a small set of neural-informed model parameters, such approaches are promising in terms of the assessment of tinnitus severity. We will first examine baseline differences in the characterization of decision-making under uncertainty between healthy individuals and people with tinnitus in terms of differences in the parameters of computational models in a cross-sectional experiment. We will also investigate whether these computational markers, which capture characteristics of decision-making, can be used to understand the cognitive impact of tinnitus symptom fluctuations through a longitudinal experimental design.

METHODS

We have developed a mobile app, AthenaCX, to deliver e-consent and baseline tinnitus and psychological assessments as well as regular ecological momentary assessments (EMAs) of perceived tinnitus loudness and a web-based aversive version of a probabilistic decision-making task, which can be triggered based on the participants' responses to the EMA surveys. Computational models will be developed to fit participants' choice data in the task, and cognitive parameters will be estimated to characterize participants' current ability to adapt learning to the change of the simulated environment at each session when the task is triggered. Linear regression analysis will be conducted to evaluate the impacts of baseline tinnitus severity on adapting decision-making performance. Repeated measures linear regression analysis will be used to examine model-derived parameters of decision-making in measuring real-time perceived tinnitus loudness fluctuations.

RESULTS

Ethics approval was received in December 2020 from Dublin City University (DCUREC/2021/070). The implementation of the experiments, including both the surveys and the web-based decision-making task, has been prepared. Recruitment flyers have been shared with audiologists, and a video instruction has been created to illustrate to the participants how to participate in the experiment. We expect to finish data collection over 12 months and complete data analysis 6 months after this. The results are expected to be published in December 2023.

CONCLUSIONS

We believe that EMA with context-aware triggering can facilitate a deeper understanding of the effects of tinnitus symptom severity upon decision-making processes as measured outside of the laboratory.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/36583.

The hearing hippocampus

The hippocampus has a well-established role in spatial and episodic memory but a broader function has been proposed including aspects of perception and relational processing. Neural bases of sound analysis have been described in the pathway to auditory cortex, but wider networks supporting auditory cognition are still being established. We review what is known about the role of the hippocampus in processing auditory information, and how the hippocampus itself is shaped by sound. In examining imaging, recording, and lesion studies in species from rodents to humans, we uncover a hierarchy of hippocampal responses to sound including during passive exposure, active listening, and the learning of associations between sounds and other stimuli. We describe how the hippocampus' connectivity and computational architecture allow it to track and manipulate auditory information - whether in the form of speech, music, or environmental, emotional, or phantom sounds. Functional and structural correlates of auditory experience are also identified. The extent of auditory-hippocampal interactions is consistent with the view that the hippocampus makes broad contributions to perception and cognition, beyond spatial and episodic memory. More deeply understanding these interactions may unlock applications including entraining hippocampal rhythms to support cognition, and intervening in links between hearing loss and dementia.

Functional changes in the auditory cortex and associated regions caused by different acoustic stimuli in patients with presbycusis and tinnitus

Presbycusis and tinnitus are the two most common hearing related pathologies. Although both of these conditions presumably originate in the inner ear, there are several reports concerning their central components. Interestingly, the onset of presbycusis coincides with the highest occurrence of tinnitus. The aim of this study was to identify age, hearing loss, and tinnitus related functional changes, within the auditory system and its associated structures. Seventy-eight participants were selected for the study based on their age, hearing, and tinnitus, and they were divided into six groups: young controls (Y-NH-NT), subjects with mild presbycusis (O-NH-NT) or expressed presbycusis (O-HL-NT), young subjects with tinnitus (Y-NH-T), subjects with mild presbycusis and tinnitus (O-NH-T), and subjects with expressed presbycusis and tinnitus (O-HL-T). An MRI functional study was performed with a 3T MRI system, using an event related design (different types of acoustic and visual stimulations and their combinations). The amount of activation of the auditory cortices (ACs) was dependent on the complexity of the stimuli; higher complexity resulted in a larger area of the activated cortex. Auditory stimulation produced a slightly greater activation in the elderly, with a negative effect of hearing loss (lower activation). The congruent audiovisual stimulation led to an increased activity within the default mode network, whereas incongruent stimulation led to increased activation of the visual cortex. The presence of tinnitus increased activation of the AC, specifically in the aged population, with a slight prevalence in the left AC. The occurrence of tinnitus was accompanied by increased activity within the insula and hippocampus bilaterally. Overall, we can conclude that expressed presbycusis leads to a lower activation of the AC, compared to the elderly with normal hearing; aging itself leads to increased activity in the right AC. The complexity of acoustic stimuli plays a major role in the activation of the AC, its support by visual stimulation leads to minimal changes within the AC. Tinnitus causes changes in the activity of the limbic system, as well as in the auditory AC, where it is bound to the left hemisphere.

The Short and Long-Term Effect of Sound Therapy on Visual Attention in Chronic Tinnitus Patients

Sound therapy is one of the most common tinnitus treatments that can be used either to mask or to shift attention away from the tinnitus percept. However, the actual benefit of sound therapy and the mechanisms leading to the benefits remain limited. The objective of this study was to investigate the short-term (15 min) and long-term (2 months) effects of sound therapy on visual attention in chronic tinnitus patients. Visual attention was evaluated with the behavioral Attention Network Task, while the tinnitus-related distress was evaluated with the Tinnitus Handicap Inventory (THI) to quantify the effect of sound therapy. The study included 20 participants with chronic and bothersome tinnitus (>6 months, THI > 18) and 20 matched control participants. All participants took part in a first session consisting of a baseline condition, a short-term sound therapy condition and a silent control condition. The tinnitus participants also took part in a second session that evaluated the long-term effect of the therapy. A reduction in the tinnitus-related distress was found after the long-term use of sound therapy. Furthermore, a reduction in the differential index of the executive control (EC) attention network, indicating improved attention, was found after long-term use of sound therapy in the sound condition but not in the silent control condition. In contrast to earlier research, no differences were found between the tinnitus group and the control group for the baseline measurement of the EC attention network. Overall, the results suggest that there is no link between the visual attention networks and the sound therapy’s effect on tinnitus-related distress.

Intrinsic Network Changes in Bilateral Tinnitus Patients with Cognitive Impairment: A Resting-State Functional MRI Study

Previous studies have found a link between tinnitus and cognitive impairment, even leading to dementia. However, the mechanisms underlying this association are not clear. The purpose of this study was to explore intrinsic network changes in tinnitus and hearing loss patients with cognitive disorders. We included 17 individuals with bilateral idiopathic tinnitus, hearing loss, and cognitive impairment (PA) and 21 healthy controls. We identified resting-state networks (RSNs) and measured intra-network functional connectivity (FC) values via independent component analysis (ICA). We also evaluated correlations between RSNs and clinical characteristics. Compared with the healthy controls, the PA group showed decreased connectivity within the ventral attention network, dorsal attention network (DAN), visual network, left frontoparietal network, right frontoparietal network, sensorimotor network, and increased connectivity within the executive control network. MoCA (Montreal Cognitive Assessment) scores were negatively correlated with the FC values for left calcarine within the DAN. We identified abnormal intrinsic connectivity in several brain networks, mainly involving cognitive control, vision, sensorimotor function, and the cerebellum, in tinnitus patients with cognitive impairment. It may be possible to use the FC strength of the left calcarine within the DAN as an imaging marker to predict cognitive impairment in tinnitus patients.

Tinnitus: impact on patients in relation to audiological findings

Objective

Tinnitus is a common auditory disorder in which patients experience noise in the absence of an external source. It is a consequence of irreversible cochlear damage. This study examined the distortion product otoacoustic emissions and P300 components of event-related potentials.

Method

This study included a control group of 25 normal-hearing adults not complaining of tinnitus and a study group that consisted of 45 normal-hearing adults complaining of tinnitus. Measures included patient history, basic audiological evaluation, the Arabic version of Tinnitus Handicap Inventory, distortion product otoacoustic emissions testing and P300 recording.

Results

The study group showed significantly higher hearing thresholds at all frequencies as well as delayed latencies and reduced amplitude of P300. The Tinnitus Handicap Inventory showed mean scores of 35.2 ± 16.9, and the distortion product gram showed higher amplitudes in the control group.

Conclusion

Patients with tinnitus might have neural dysfunction at either peripheral or central levels of the auditory pathway.

Tinnitus Affects Endogenous But Not Exogenous Auditory Attention Orienting

Purpose:

Previous studies have demonstrated that people with tinnitus show attention dysfunctions. In this study, we investigated the influence of tinnitus on attention orienting, especially whether the ability of attention orienting could be modulated by the degree of tinnitus.

Method:

Fifty-nine and 54 unilateral tinnitus participants were included in Experiment 1 and Experiment 2, respectively. All participants reported subjective tinnitus for at least 3 months and were divided into a mild tinnitus group (Tinnitus Handicap Inventory [THI] < 37) or a moderate to severe tinnitus group (THI ≥ 37) according to the THI score. An auditory exogenous attention task and an auditory endogenous attention task were adopted. In the exogenous task, a target sound following a cue sound was presented on either the left or right side. Participants were required to discriminate whether the target was pure tone or white noise. In the endogenous task, participants were required to pay attention to the stimuli on one side and judge the pitch of a target sound. Mixed-design analyses of variance were conducted for the mean reaction times and accuracy across the experimental conditions.

Results:

Our results showed that in the endogenous attention task, compared with the mild tinnitus group, moderate to severe tinnitus participants had better performance for stimuli presented on the tinnitus side but not on the nontinnitus side. In contrast, in the exogenous attention task, no differences were found between mild and moderate to severe tinnitus groups.

Conclusion:

The results suggest that the degree of tinnitus influences the performance of auditory endogenous attention but not auditory exogenous attention orienting.

Dose-Response Transcranial Electrical Stimulation Study Design: A Well-Controlled Adaptive Seamless Bayesian Method to Illuminate Negative Valence Role in Tinnitus Perception

The use of transcranial Electrical Stimulation (tES) in the modulation of cognitive brain functions to improve neuropsychiatric conditions has extensively increased over the decades. tES techniques have also raised new challenges associated with study design, stimulation protocol, functional specificity, and dose-response relationship. In this paper, we addressed challenges through the emerging methodology to investigate the dose-response relationship of High Definition-transcranial Direct Current Stimulation (HD tDCS), identifying the role of negative valence in tinnitus perception. In light of the neurofunctional testable framework and tES application, hypotheses were formulated to measure clinical and surrogate endpoints. We posited that conscious pairing adequately pleasant stimuli with tinnitus perception results in correction of the loudness misperception and would be reinforced by concurrent active HD-tDCS on the left Dorsolateral Prefrontal Cortex (dlPFC). The dose-response relationship between HD-tDCS specificity and the loudness perception is also modeled. We conducted a double-blind, randomized crossover pilot study with six recruited tinnitus patients. Accrued data was utilized to design a well-controlled adaptive seamless Bayesian dose-response study. The sample size (n = 47, for 90% power and 95% confidence) and optimum interims were anticipated for adaptive decision-making about efficacy, safety, and single session dose parameters. Furthermore, preliminary pilot study results were sufficient to show a significant difference (90% power, 99% confidence) within the longitudinally detected self-report tinnitus loudness between before and under positive emotion induction. This study demonstrated a research methodology used to improve emotion regulation in tinnitus patients. In the projected method, positive emotion induction is essential for promoting functional targeting under HD-tDCS anatomical specificity to indicate the efficacy and facilitate the dose-finding process. The continuous updating of prior knowledge about efficacy and dose during the exploratory stage adapts the anticipated dose-response model. Consequently, the effective dose range to make superiority neuromodulation in correcting loudness misperception of tinnitus will be redefined. Highly effective dose adapts the study to a standard randomized trial and transforms it into the confirmatory stage in which active HD-tDCS protocol is compared with a sham trial (placebo-like). Establishing the HD-tDCS intervention protocols relying on this novel method provides reliable evidence for regulatory agencies to approve or reject the efficacy and safety. Furthermore, this paper supports a technical report for designing multimodality data-driven complementary investigations in emotion regulation, including EEG-driven neuro markers, Stroop-driven attention biases, and neuroimaging-driven brain network dynamics.

Investigation of the Relation Between Tinnitus, Cognition, and the Amount of Listening Effort

PURPOSE

This study aimed to investigate the effect of chronic tinnitus on measures of listening effort and cognitive performance, as well as the relation between cognitive performance and the amount of listening effort obtained by those measures.

METHOD

Thirteen normal-hearing young adults with chronic tinnitus were matched with a control group. First, behavioral listening effort was measured using a dual-task paradigm in various favorable and unfavorable listening conditions. Furthermore, verbal working memory, processing speed, selective attention, and cognitive flexibility and inhibition were evaluated.

RESULTS

A significant and nonsignificant trend toward more listening effort in the tinnitus group was, respectively, found for the quiet listening condition and the condition with a signal-to-noise ratio of +2 dB. No significant differences in cognitive performances were found between the groups, nor were there significant relationships between the cognitive factors and listening effort scores for either the control or tinnitus group.

CONCLUSIONS

Listening effort was increased in the tinnitus group. Although no clear differences in cognitive performance could be found between the tinnitus group and their controls, a trend could be seen whereby selective attention deficits in the subjects with tinnitus may be an important factor that affects the amount of listening effort.

Effect of Auditory Discrimination Therapy on Attentional Processes of Tinnitus Patients

Tinnitus is an auditory condition that causes humans to hear a sound anytime, anywhere. Chronic and refractory tinnitus is caused by an over synchronization of neurons. Sound has been applied as an alternative treatment to resynchronize neuronal activity. To date, various acoustic therapies have been proposed to treat tinnitus. However, the effect is not yet well understood. Therefore, the objective of this study is to establish an objective methodology using electroencephalography (EEG) signals to measure changes in attentional processes in patients with tinnitus treated with auditory discrimination therapy (ADT). To this aim, first, event-related (de-) synchronization (ERD/ERS) responses were mapped to extract the levels of synchronization related to the auditory recognition event. Second, the deep representations of the scalograms were extracted using a previously trained Convolutional Neural Network (CNN) architecture (MobileNet v2). Third, the deep spectrum features corresponding to the study datasets were analyzed to investigate performance in terms of attention and memory changes. The results proved strong evidence of the feasibility of ADT to treat tinnitus, which is possibly due to attentional redirection.

Psychophysiological treatment of chronic tinnitus: A review

Subjective chronic tinnitus consists of a more or less continuous perception of sound in the absence of a corresponding acoustic source, which can lead to various psychological problems like depression, anxiety, attentional deficits and sleep disturbances. The prevalence is 10%-15% of the general population. Various therapy and management options have been proposed, but outcomes vary, and no generally accepted cure exists. In this review, the coherence of the most frequently used aetiological models shall be evaluated, and the efficacy of several treatment options will be discussed. With respect to tinnitus treatments, we focus on controlled studies and meta-analyses. Although there are some therapies that outweigh placebo effects such as cognitive behavioural therapy, neurofeedback or neuromodulation techniques, they mainly target secondary symptoms and not the tinnitus tone itself. Furthermore, positive treatment effects only seem to last for a limited period of time. We conclude that long-lasting combination therapies such as neurofeedback of auditory cortex inhibitory EEG signatures, cognitive therapy and sound-tactile stimulation may provide more efficient outcomes if they target the intensity of the tinnitus tone itself and not only secondary psychological symptoms.

Systematic review and meta-analysis on the effect of continuous subjective tinnitus on attention and habituation

Background

Attention and habituation are two domains known to play key roles in the perception and maintenance of tinnitus. The heterogeneous nature of tinnitus and the methodologies adopted by various studies make it difficult to generalize findings. The current review aims at assessing and synthesizing evidence on the possible roles of attention and habituation in continuous subjective tinnitus.

Methodology

The literature search included five databases (PubMed, Scopus, Web of Sciences, CINAHL and ProQuest) that resulted in 1,293 articles, published by July 2019. Studies on attention and/or habituation in individuals with tinnitus using either behavioural or electrophysiological tests were included in the review after a quality assessment.

Results

Seventeen studies on attention in tinnitus were included in the narrative synthesis. Two meta-analyses were performed to assess the role of attention in tinnitus using a behavioural methodology (z = 4.06; p < 0.0001) and P300 amplitude (z = 2.70; p = 0.007) with 531 participants. With respect to habituation, the review indicates the lack of quality articles for habituation inclusion in the narrative synthesis.

Conclusions

The review highlights that selective domains of attention were consistently impaired in individuals with tinnitus. Habituation, on the other hand, needs further exploration.

Factors Associated With Hearing Aid Wear Time in a Subset of U.S. Military Veterans: Tinnitus, the Presence of One or More Neurologic Conditions, and Unaided Speech Intelligibility Index

PURPOSE

A retrospective analysis was conducted to explore how tinnitus, one or more neurologic conditions, unaided speech intelligibility index, and other comorbidities impact the average number of hours hearing aids are worn each day by U.S. Military Veterans.

METHOD

Medical records and a hearing aid database were queried to obtain information regarding active medical problems and average daily hearing aid wear time. Multiple linear regression was used to explore these relationships for 215 male Veterans whose records were available from 2009 to 2020. To be analyzed, Veterans must have possessed their hearing aid(s) for at least 3 consecutive months.

RESULTS

An active problem of subjective tinnitus was associated with increased hearing aid wear time (positive association) and one or more active neurologic conditions were associated with decreased hearing aid wear time (negative association). A high unaided speech intelligibility index (greater access to speech sounds without hearing aids) was also associated with decreased hearing aid wear time (negative association).

CONCLUSIONS

There are many complex audiologic and medical concerns that may affect hearing aid wear time in U.S. Military Veterans. Therefore, the information from this study should be expanded on prospectively by further exploring these associations, and their severity, on hearing aid wear time. The information from this and future studies may lead to clinical recommendations with the goal of increasing daily hearing aid use in this and other populations.

Tinnitus Is Associated With Improved Cognitive Performance in Non-hispanic Elderly With Hearing Loss

Because hearing loss is a high-risk factor for cognitive decline, tinnitus, a comorbid condition of hearing loss, is often presumed to impair cognition. The present cross-sectional study aimed to delineate the interaction of tinnitus and cognition in the elderly with and without hearing loss after adjusting for covariates in race, age, sex, education, pure tone average, hearing aids, and physical well-being. Participants included 643 adults (60–69 years old; 51.3% females) from the National Health and Nutrition Examination Survey (NHANES, 2011–2012), and 1,716 (60–69 years old; 60.4% females) from the Hispanic Community Health Study (HCHS, 2008–2011). Multivariable linear and binary logistic regression was used to assess the association between tinnitus and cognition in the two sub-cohorts of normal hearing (NHANES, n = 508; HCHS, n = 1264) and hearing loss (NHANES, n = 135; HCHS, n = 453). Cognitive performance was measured as a composite z-score from four cognitive tests: The Consortium to Establish a Registry for Alzheimer’s Disease (CERAD)-word learning, CERAD-animal fluency, CERAD-word list recall, and the digit symbol substitution test (DSST) in NHANES, and a comparable Hispanic version of these four tests in HCHS. Multivariable linear regression revealed no association between tinnitus and cognition, except for the NHANES (non-Hispanic) participants with hearing loss, where the presence of tinnitus was associated with improved cognitive performance (Mean = 0.3; 95% CI, 0.1–0.5; p, 0.018). Using the 25th percentile score of the control (i.e., normal hearing and no tinnitus) as a threshold for poor cognitive performance, the absence of tinnitus increased the risk for poor cognitive performance (OR = 5.6, 95% CI, 1.9–17.2; p, 0.002). Sensitivity analysis found a positive correlation between tinnitus duration and cognitive performance in the NHANES cohort [F(4,140), 2.6; p, 0.037]. The present study finds no evidence for the assumption that tinnitus impairs cognitive performance in the elderly. On the contrary, tinnitus is associated with improved cognitive performance in the non-Hispanic elderly with hearing loss. The present result suggests that race be considered as an important and relevant factor in the experimental design of tinnitus research. Future longitudinal and imaging studies are needed to validate the present findings and understand their mechanisms.

Job satisfaction in a group of patients with tinnitus

BACKGROUND

Tinnitus is an auditory impression without any external auditory stimulus. It may cause negative symptoms (anxiety, insomnia, depression) significantly affecting work performance and job satisfaction.

OBJECTIVE

To evaluate the job satisfaction in tinnitus sufferers.

METHODS

Cross-sectional study were conducted and 51 individuals (23-70 years) were recruited. Participants completed two questionnaires: Tinnitus Handicap Inventory and Job Satisfaction Scale.

RESULTS

People affected by tinnitus report higher job satisfaction than healthy people. Job satisfaction was significantly related to age: r = 0.31; p < 0.05 in all tinnitus patients. There was a correlation between job satisfaction and tinnitus severity but only in people with normal hearing (-0.69; p < 0.05).

CONCLUSIONS

The results show that job satisfaction is affected by the level of tinnitus annoyance (from both its emotional and functional aspects), but only in people with normal hearing. In future research it is recommended that additional factors be investigated, both work and non-work related, to thoroughly explore the impact of tinnitus on job satisfaction.

Auditory thalamus dysfunction and pathophysiology in tinnitus: a predictive network hypothesis

Tinnitus is the perception of a 'ringing' sound without an acoustic source. It is generally accepted that tinnitus develops after peripheral hearing loss and is associated with altered auditory processing. The thalamus is a crucial relay in the underlying pathways that actively shapes processing of auditory signals before the respective information reaches the cerebral cortex. Here, we review animal and human evidence to define thalamic function in tinnitus. Overall increased spontaneous firing patterns and altered coherence between the thalamic medial geniculate body (MGB) and auditory cortices is observed in animal models of tinnitus. It is likely that the functional connectivity between the MGB and primary and secondary auditory cortices is reduced in humans. Conversely, there are indications for increased connectivity between the MGB and several areas in the cingulate cortex and posterior cerebellar regions, as well as variability in connectivity between the MGB and frontal areas regarding laterality and orientation in the inferior, medial and superior frontal gyrus. We suggest that these changes affect adaptive sensory gating of temporal and spectral sound features along the auditory pathway, reflecting dysfunction in an extensive thalamo-cortical network implicated in predictive temporal adaptation to the auditory environment. Modulation of temporal characteristics of input signals might hence factor into a thalamo-cortical dysrhythmia profile of tinnitus, but could ultimately also establish new directions for treatment options for persons with tinnitus.

Risk of early-onset dementia among persons with tinnitus: a retrospective case-control study

Higher rates of poor cognitive performance are known to prevail among persons with tinnitus in all age groups. However, no study has explored the association between tinnitus and early-onset dementia. We hypothesize that tinnitus may precede or occur concurrently with subclinical or early onset dementia in adults younger than 65 years of age. This case–control study used data from the Taiwan National Health Insurance Research Database, identifying 1308 patients with early-onset dementia (dementia diagnosed before 65 years of age) and 1308 matched controls. We used multivariable logistic regressions to estimate odds ratios (ORs) for prior tinnitus among patients with dementia versus controls. Among total 2616 sample participants, the prevalence of prior tinnitus was 18%, 21.5% among cases and 14.5% among controls (p < 0.001). Multivariable logistic regression showed and adjusted OR for prior tinnitus of 1.6 for cases versus controls (95% CI: 1.3 ~ 2.0). After adjusting for sociodemographic characteristics and medical co-morbidities, patients with early-onset dementia had a 67% higher likelihood of having prior tinnitus (OR = 1.628; 95% CI = 1.321–2.006). Our findings showed that pre-existing tinnitus was associated with a 68% increased risk of developing early-onset dementia among young and middle-aged adults. The results call for greater awareness of tinnitus as a potential harbinger of future dementia in this population.

Functional impact of bothersome tinnitus on cognitive test performance

OBJECTIVE

Individuals with bothersome tinnitus frequently report their concentration is affected. Given that tinnitus is the leading service-connected disability compensated by the United States Department of Veterans Affairs, it is essential to determine whether tinnitus has a functional impact on the operational performance of Service members. Previous studies demonstrated that people with tinnitus perform more poorly on cognitive tests of selective attention and memory than those without tinnitus. This study aimed to compare performance between participants with and without tinnitus on visually based tests of selective attention (flanker task) and short-term memory (spatial letter location) that were self-administered under three auditory conditions (quiet, broadband noise and speech) using a tablet-based test protocol.

DESIGN

Experimental.

STUDY SAMPLE

Thirty participants with bothersome tinnitus and 30 control participants, matched for age and hearing loss.

RESULTS

The results revealed a significantly larger flanker effect and shorter memory span in the tinnitus group compared to the control group, consistent with previous studies. Performance accuracy was comparable between the groups.

CONCLUSIONS

The results suggest bothersome tinnitus may affect cognitive efficiency more than cognitive performance. The tablet-based protocol has the potential to be implemented clinically as a functional measure of the impact of bothersome tinnitus on concentration.

Behavioral Outcomes and Neural Network Modeling of a Novel, Putative, Recategorization Sound Therapy

The mechanisms underlying sound's effect on tinnitus perception are unclear. Tinnitus activity appears to conflict with perceptual expectations of "real" sound, resulting in it being a salient signal. Attention diverted towards tinnitus during the later stages of object processing potentially disrupts high-order auditory streaming, and its uncertain nature results in negative psychological responses. This study investigated the benefits and neurophysiological basis of passive perceptual training and informational counseling to recategorize phantom perception as a more real auditory object. Specifically, it examined underlying psychoacoustic correlates of tinnitus and the neural activities associated with tinnitus auditory streaming and how malleable these are to change with targeted intervention. Eighteen participants (8 females, 10 males, mean age = 61.6 years) completed the study. The study consisted of 2 parts: (1) An acute exposure over 30 min to a sound that matched the person's tinnitus (Tinnitus Avatar) that was cross-faded to a selected nature sound (Cicadas, Fan, Water Sound/Rain, Birds, Water and Bird). (2) A chronic exposure for 3 months to the same "morphed" sound. A brain-inspired spiking neural network (SNN) architecture was used to model and compare differences between electroencephalography (EEG) patterns recorded prior to morphing sound presentation, during, after (3-month), and post-follow-up. Results showed that the tinnitus avatar generated was a good match to an individual's tinnitus as rated on likeness scales and was not rated as unpleasant. The five environmental sounds selected for this study were also rated as being appropriate matches to individuals' tinnitus and largely pleasant to listen to. There was a significant reduction in the Tinnitus Functional Index score and subscales of intrusiveness of the tinnitus signal and ability to concentrate with the tinnitus trial end compared to baseline. There was a significant decrease in how strong the tinnitus signal was rated as well as ratings of how easy it was to ignore the tinnitus signal on severity rating scales. Qualitative analysis found that the environmental sound interacted with the tinnitus in a positive way, but participants did not experience change in severity, however, characteristics of tinnitus, including pitch and uniformity of sound, were reported to change. The results indicate the feasibility of the computational SNN method and preliminary evidence that the sound exposure may change activation of neural tinnitus networks and greater bilateral hemispheric involvement as the sound morphs over time into natural environmental sound; particularly relating to attention and discriminatory judgments (dorsal attention network, precentral gyrus, ventral anterior network). This is the first study that attempts to recategorize tinnitus using passive auditory training to a sound that morphs from resembling the person's tinnitus to a natural sound. These findings will be used to design future-controlled trials to elucidate whether the approach used differs in effect and mechanism from conventional Broadband Noise (BBN) sound therapy.

On the relationship between tinnitus distress, cognitive performance and aging

In this study we analyzed psychometric data of 107 individuals who suffer from chronic subjective tinnitus. In particular, we elucidated the relationship between tinnitus-related distress, psychological comorbidities, age, and hearing, and the performance in cognitive concentration and interference tests. Previous research has provided first evidence that individuals with tinnitus may have deficits in cognitive tasks. The present study aimed at extending former research by investigating the relationship between tinnitus distress and cognition. Statistical analyses comprised correlation and regression approaches. We observed a significant relationship between tinnitus distress (tinnitus score, TQ), age and hearing loss and the performance in tests on selective and sustained attention (d2 test) and cognitive interference (Stroop test). Tinnitus distress was identified as the most important predictor of cognitive performance (additionally age for cognitive interference). For other psychometric variables (perceived stress, PSQ; self-efficacy, optimism and pessimism, SWOP) and hearing loss we could not find any meaningful relationship with cognitive performance. The results clearly point to a (currently non-causal) relationship between cognitive skills and distress of tinnitus-related symptoms. Furthermore, the influence of age is noteworthy as this finding implies that with increasing age an appropriate coping with aversive tinnitus symptoms based on proper cognitive functions and age-related hearing dysfunctions, namely inhibition, may become more difficult. Hence, it is suggested to consider cognitive tests as a supplementary measurement in clinical assessment of tinnitus and to raise awareness for the impairing influence of tinnitus on cognition in daily life.

Investigating the Impact of Cognitive Training for Individuals With Bothersome Tinnitus: A Randomized Controlled Trial

OBJECTIVE

To evaluate the effectiveness of cognitive training in improving tinnitus bother and to identify predictors of patient response.

STUDY DESIGN

Prospective open-label randomized controlled trial.

SETTING

Online.

METHODS

Participants were adults with subjective idiopathic nonpulsatile tinnitus causing significant tinnitus-related distress. The intervention group trained by using auditory-intensive exercises for 20 minutes per day, 5 days per week, for 8 weeks. The active control group trained on the same schedule with non-auditory intensive games. Surveys were completed at baseline, 8 weeks, and 12 weeks.

RESULTS

A total of 64 participants completed the study. The median age was 63 years (range, 25-69) in the intervention group and 61 years (34-68) in the control group. Mixed model analysis revealed that within-subject change in Tinnitus Functional Index in the intervention group was not different than the control group, with marginal mean differences (95% CI): 0.24 (-11.20 to 10.7) and 2.17 (-8.50 to 12.83) at 8 weeks and 2.33 (-8.6 to 13.3) and 3.36 (-7.91 to 14.6) at 12 weeks, respectively. When the 2 study groups were compared, the control group had higher Tinnitus Functional Index scores than the intervention group by 10.5 points at baseline (95% CI, -0.92 to 29.89), 8.1 at 8 weeks (95% CI, -3.27 to 19.42), and 9.4 at 12 weeks (95% CI, -2.45 to 21.34).

CONCLUSION

Auditory-intensive cognitive training was not associated with changes in self-reported tinnitus bother. Given the potential for neuroplasticity to affect tinnitus, we believe that future studies on cognitive training for tinnitus remain relevant.

Does Cognitive Dysfunction Correlate With Dizziness Severity in Meniére's Disease Patients

OBJECTIVE

Characterize the relationship between cognitive dysfunction and the dizziness severity in Meniére's disease (MD) patients.

STUDY DESIGN

Retrospective review.

SETTING

University-based tertiary medical center.

PATIENTS

Three hundred patients were evaluated for MD from 2015 to 2019. Excluding comorbid or alternative vestibular disorders, 29 patients with definite MD and available pre- and postintervention data were included for analysis.

INTERVENTIONS

A progressive protocol of salt restriction, diuretics, steroid and/or gentamycin injection, and endolymphatic sac decompression for those refractory to medical therapy.

MAIN OUTCOME MEASURES

Quality of life measured with the Dizziness Handicap Inventory (DHI) and cognitive function measured with the Cognitive Failures Questionnaire (CFQ). Pre- and posttreatment DHI and DHI subscale scores and change in these scores were correlated with pre- and posttreatment CFQ scores and change in CFQ with therapy.

RESULTS

Analysis showed a number of limited associations between improvement in DHI and improvement in CFQ. Total DHI scores failed to correlate scores or variation in scores with change in CFQ (p = 0.091 and p = 0.085, respectively). Improvement in the CFQ false-triggering domain was significantly associated with improvement in the DHI physical subscale (r = 0.491, p = 0.007) and was nonsignificantly associated with improvement in total DHI and DHI emotional subscale scores (r = 0.422, p = 0.016 and r = 0.399, p = 0.032).

CONCLUSIONS

The DHI correlates with several pre- and posttreatment measures of cognitive dysfunction (CFQ) in MD patients. However, change in DHI and CFQ with therapy correlate poorly. Overall, the commonly used DHI may fail to adequately assess cognitive dysfunction in MD patients possibly due to factors not directly implicated by measures of vestibular dysfunction, such as central nervous system or cognitive dysfunction; however, the specific physical and emotional subscales may offer helpful insight into cognitive dysfunction change/improvement with treatment.

Phonetic perception but not perception of speaker gender is impaired in chronic tinnitus

While tinnitus is known to compromise the perception of speech, it is unclear if the same holds for extralinguistic speaker information. Furthermore, research with simple tone stimuli showed that unilateral tinnitus binds spatial attention, thereby impeding the detection of auditory changes in the non-affected ear. Using dichotic listening tasks, we tested left-ear tinnitus patients and control patients for their ability to ignore speech and speaker information in the task-irrelevant ear. To this end they heard vowel-consonant-vowel (VCV) syllables simultaneously spoken by gender-ambiguous voices in one ear and male or female voices in the contralateral ear. They selectively attended to speech (Exp. 1) or speaker (Exp. 2) information in a designated target ear, by classifying either the consonant (/b/ or /g/) in VCV syllables or voice gender (male or female) while ignoring distractor voices in the other ear. While performance was comparable across groups in the gender task, tinnitus patients responded slower than controls in the consonant task, with no effect of target ear. This suggests that tinnitus hampers phonetic perception in speech, while preserving the processing of extralinguistic speaker information. These findings support the growing evidence for speech perception impairments in tinnitus.

The Association Between Effectiveness of Tinnitus Intervention and Cognitive Function-A Systematic Review

Tinnitus refers to the perception of sound in the absence of an external stimulus. This can be problematic and can lead to health problems in some sufferers, including effects on cognitive functions such as attention and memory. Although several studies have examined the effectiveness of tinnitus interventions, e.g., cognitive behavioral therapy and sound therapy, it is still unclear as to the overall quality and limitations of these studies and whether their results could be generalized. Clarification is also needed as to whether poor cognitive function will lead to a less favorable intervention outcome in tinnitus patients. The present systematic review was therefore designed to critically appraise and synthesize findings from randomized controlled trials (RCTs) of tinnitus intervention and its effects on cognition. The methodology followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Medline (PubMed), Embase, and PsycINFO were searched. Only RCTs that compared the effectiveness of a tinnitus intervention and a measure of cognitive function in adult participants with tinnitus were included. A total of 8 studies involving 610 participants tested using 11 cognitive function assessment tools (e.g., Stroop Color and Word Test and Visual Continuous Performance Task) and 5 tinnitus intervention outcome measurements (e.g., Tinnitus Handicap Inventory and Tinnitus Questionnaire) were included and analyzed. The outcomes of the review suggest that tinnitus intervention not only facilitates tinnitus management but also improves cognitive functions. It is likely that cognition and emotion play an important role in a patient's adjustment to tinnitus. Whether cognition can predict treatment outcomes is unclear due to insufficient evidence. Future research is needed using a standardized assessment protocol focusing on the effect of sound-based interventions on tinnitus severity and cognitive functions. Studies on whether cognitive function measurement can be used as a predictor for the effectiveness of tinnitus therapy are also needed.

Systematic review and meta-analysis of late auditory evoked potentials as a candidate biomarker in the assessment of tinnitus

Subjective tinnitus, the perception of sound in the absence of any sound source, is routinely assessed using questionnaires. The subjective nature of these tools hampers objective evaluation of tinnitus presence, severity and treatment effects. Late auditory evoked potentials (LAEPs) might be considered as a potential biomarker for assessing tinnitus complaints. Using a multivariate meta-analytic model including data from twenty-one studies, we determined the LAEP components differing systematically between tinnitus patients and controls. Results from this model indicate that amplitude of the P300 component is lower in tinnitus patients (standardized mean difference (SMD) = -0.83, p < 0.01), while latency of this component is abnormally prolonged in this population (SMD = 0.97, p < 0.01). No other investigated LAEP components were found to differ between tinnitus and non-tinnitus subjects. Additional sensitivity analyses regarding differences in experimental conditions confirmed the robustness of these results. Differences in age and hearing levels between the two experimental groups might have a considerable impact on LAEP outcomes and should be carefully considered in future studies. Although we established consistent differences in the P300 component between tinnitus patients and controls, we could not identify any evidence that this component might covary with tinnitus severity. We conclude that out of several commonly assessed LAEP components, only the P300 can be considered as a potential biomarker for subjective tinnitus, although more research is needed to determine its relationship with subjective tinnitus measures. Future trials investigating experimental tinnitus therapies should consider including P300 measurements in the evaluation of treatment effect.

Tinnitus and cognition: Can load theory help us refine our understanding?

Objective: Tinnitus has been shown to be associated with specific cognitive deficits. Contemporary models of tinnitus, based primarily on human behavior, emphasize the influence of the cognitive response to tinnitus in tinnitus manifestation and level of associated annoyance. The models and hypotheses proposed thus far have (a) focused on the cognitive response to the onset of tinnitus, and not necessarily focused on the cognitive consequences of established chronic tinnitus, and (b) failed to dissociate the contributions of cognitive and perceptual load in their theories. Load theory states that we have a limited capacity of neural resources that can be used to process internal and external stimuli. This theory is differentially applied to perceptual load, which refers to the neural resources engaged in the processing of sensory stimuli in our environment, and cognitive load, which refers to the occupation of a more central resource that is involved in higher-level processing, such as stimulus discrimination, decision making, and working memory processing. Methods: A focused review was conducted on behavioral and brain-imaging studies examining cognitive deficits in tinnitus, in an attempt to reexamine the findings in a load theory framework. Results: Findings of these studies are discussed in the context of load theory, and a novel model for understanding these findings is proposed. Conclusion: We believe the incorporation of load theory into models of tinnitus may advance understanding of the cognitive impact of tinnitus and lead to better management of tinnitus.

Assessment of the Effectiveness of Transcranial Magnetic Stimulation in Subjective Tinnitus

Introduction  Increases in spontaneous activity in the neurons of the auditory cortex are presumed as the pathophysiology of tinnitus.

Objective  To investigate the effectiveness of transcranial magnetic stimulation (TMS) in the treatment of tinnitus.

Methods  A total of 62 patients between the ages of 22 and 74 with chronic subjective tinnitus were enrolled in the study. The inclusion criteria were normal findings on an otolaryngologic examination and normal ranges of complete blood count, routine biochemical parameter levels, thyroid function, air-bone gap on pure-tone audiometry, and middle-ear pressure and stapedial reflex on tympanometry. The patients were randomized into 2 groups: 40 patients were placed in the treatment for TMS (tTMS) group, and the rest (22 patients) were placed in the sham TMS group. The frequency and severity of the tinnitus, as well as the tinnitus handicap inventory (THI) score of each patient were measured before and one month after the treatment, and the values were statistically evaluated.

Results  We observed a statistically significant improvement in the tTMS group ( p  < 0.05 and p  < 0.05 respectively) regarding the THI and tinnitus severity scores. The sham TMS group showed no significant improvement in terms of the THI ( p  > 0.05). However, the tinnitus severity showed a significant increase in this group ( p  < 0.05). The comparison of differences in the changes in the THI and the tinnitus severity scores showed a significant statistical improvement in the tTMS group compared with the sham TMS group ( p  < 0.05 and p  < 0.05 respectively).

Conclusion  Transcranial magnetic stimulation was found to be effective in the treatment of tinnitus, and may be adopted as a treatment for tinnitus after further comprehensive studies.

Associations Between Subjective Tinnitus and Cognitive Performance: Systematic Review and Meta-Analyses

Tinnitus is the perception of sound in the absence of a corresponding external sound source, and bothersome tinnitus has been linked to poorer cognitive performance. This review comprehensively quantifies the association between tinnitus and different domains of cognitive performance. The review protocol was preregistered and published in a peer-reviewed journal. The review and analyses were reported according to Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Peer-reviewed literature was searched using electronic databases to find studies featuring participants with tinnitus who had undertaken measures of cognitive performance. Studies were assessed for quality and categorized according to an established cognitive framework. Random-effects meta-analyses were performed on various cognitive domains with potential moderator variables assessed where possible. Thirty-eight records were included in the analysis from a total of 1,863 participants. Analyses showed that tinnitus is associated with poorer executive function, processing speed, general short-term memory, and general learning and retrieval. Narrow cognitive domains of Inhibition and Shifting (within executive function) and learning and retrieval (within general learning and retrieval) were also associated with tinnitus.

Maintaining the legacy and moving forward: The new tinnitus questionnaire short form version 2

OBJECTIVE

The original 52-item version of the Tinnitus Questionnaire (TQ) is a widely applied self-report instrument to measure tinnitus-related distress. One objective of the current study was the validation of the reported five-factor structure of the German TQ in a new, large sample of patients with chronic tinnitus. Since former studies have yielded conflicting results for the factor structure of the 12-item short version (Mini-TQ), analysis of its factor structure and the generation of a new short version were further study aims.

METHODS

Data of 7112 subsequent patients with chronic tinnitus that filled out the German 52-item version of the TQ at the Tinnitus Center at Charité University Hospital Berlin, Germany, were included in the study. Statistical analyses included exploratory factor analysis (EFA) and confirmatory factor analysis (CFA).

RESULTS

CFA showed reasonably acceptable fit indices for a five-factor model for the 52-item version of the TQ, at least for RMSEA, one of the three fit indices (RMSEA = 0.059; CFI = 0.871; TLI = 0.861). Factors were called emotional distress, auditory perceptual difficulties, intrusiveness, sleep disturbances, and coping. Another CFA supports a three-factor model of the newly generated 15-item short version (RMSEA = 0.060; CFI = 0.942; TLI = 0.931) with the factors emotional distress, auditory perceptual difficulties, and intrusiveness.

CONCLUSION

Validation of the German 52-item version of the TQ in a large, new sample of patients with chronic tinnitus supports the previously reported five-factor structure with slight differences concerning the identified factors. The new three-factorial 15-item short version allows a more rapid and economical assessment of tinnitus-related distress.

Novel Risk Loci in Tinnitus and Causal Inference With Neuropsychiatric Disorders Among Adults of European Ancestry

Importance

Tinnitus affects at least 16 million US adults, but its pathophysiology is complicated, and treatment options remain limited. A heritable component has been identified in family and twin studies; however, no large-scale genome-wide association studies (GWAS) have been accomplished.

Objective

To identify genetic risk loci associated with tinnitus, determine genetic correlations, and infer possible relationships of tinnitus with hearing loss and neuropsychiatric disorders and traits.

Design, Setting, and Participants

A GWAS of self-reported tinnitus was performed in the UK Biobank (UKB) cohort using a linear mixed-model method implemented in BOLT-LMM (linear mixed model). Replication of significant findings was sought in the nonoverlapping US Million Veteran Program (MVP) cohort. A total of 172 995 UKB (discovery) and 260 832 MVP (replication) participants of European ancestry with self-report regarding tinnitus and hearing loss underwent genomic analysis. Linkage-disequilibrium score regression and mendelian randomization were performed between tinnitus and hearing loss and neuropsychiatric disorders. Data from the UKB were acquired and analyzed from September 24, 2018, to December 13, 2019. Data acquisition for the MVP cohort was completed July 22, 2019. Data analysis for both cohorts was completed on February 11, 2020.

Main Outcomes and Measures

Estimates of single nucleotide variation (SNV)-based heritability for tinnitus, identification of genetic risk loci and genes, functional mapping, and replication were performed. Genetic association and inferred causality of tinnitus compared with hearing loss and neuropsychiatric disorders and traits were analyzed.

Results

Of 172 995 UKB participants (53.7% female; mean [SD], 58.0 [8.2] years), 155 395 unrelated participants underwent SNV-based heritability analyses across a range of tinnitus phenotype definitions that explained approximately 6% of the heritability. The GWAS based on the most heritable model in the full UKB cohort identified 6 genome-wide significant loci and 27 genes in gene-based analyses, with replication of 3 of 6 loci and 8 of 27 genes in 260 832 MVP cohort participants (92.8% men; mean [SD] age, 63.8 [13.2] years). Mendelian randomization indicated that major depressive disorder had a permissive effect (β = 0.133; P = .003) and years of education had a protective effect (β = -0.322, P = <.001) on tinnitus, whereas tinnitus and hearing loss inferred a bidirectional association (β = 0.072, P = .001 and β = 1.546, P = <.001, respectively).

Conclusions and Relevance

This large GWAS characterizes the genetic architecture of tinnitus, demonstrating modest but significant heritability and a polygenic profile with multiple significant risk loci and genes. Genetic correlation and inferred causation between tinnitus and major depressive disorder, educational level, and hearing impairment were identified, consistent with clinical and neuroimaging evidence. These findings may guide gene-based diagnostic and therapeutic approaches to this pervasive disorder.

The impact of tinnitus on working memory capacity

OBJECTIVE

To determine if tinnitus was related to working memory (WM) in adults and if tinnitus handicap was related to WM in adults with tinnitus.

DESIGN

Two groups, cross-sectional design.

STUDY SAMPLES

76 adults forming a tinnitus group (n = 38) and a control group (n = 38). Each group included 19 adults with normal hearing and 19 adults with hearing loss matched for age, sex and educational backgrounds. All participants completed the visual n-back test; pure tone audiometry (0.125-16 kHz); and the Hospital Anxiety and Depression Scale (HADS). Tinnitus sufferers also completed the Tinnitus Handicap Inventory (THI).

RESULTS

For all participants, tinnitus was not related to WM scores when corrected for hearing thresholds, anxiety, and depression. The corrections for best ear high-frequency pure-tone average hearing threshold (BEHFPTA: 10, 12.5, 14 and 16 kHz) were significant. For tinnitus sufferers, THI was related to WM scores in the easiest n-back condition, and BEHFPTA was related to WM scores in the easiest and the hardest n-back condition.

CONCLUSION

Tinnitus was not related to WM scores. Tinnitus handicap was related to some WM scores in tinnitus sufferers. Further investigation of the possible relationship between high-frequency hearing and WM is warranted.

Assessment of Stroop Color Word Interference Test-TBAG form performance in subjects with tinnitus

PURPOSE

To evaluate ordinary behavioral pattern suppression performance of individuals with tinnitus under disruptive effect using Stroop Color Word Interference Test-TBAG Form (SCWT), and to determine the impact of acoustic stimulus on this performance.

METHODS

40 individuals with subjective tinnitus at Slight and higher severity according to Tinnitus Handicap Inventory (THI) (16 females, 24 males; mean age: 42.02 ± 10.00) (Study group), and 40 healthy individuals (Control group) (18 females, 22 males; mean age: 38.85 ± 10.25) were included in this study. All individuals were subjected to audiological evaluation. SCWT was applied with and without acoustic stimulus (NB noise), and test completion durations were recorded.

RESULTS

It was determined that the duration for completion of 5 sections of SCWT, both in the presence of and without acoustic stimulus, was longer in the Study group than the control group. In the presence of acoustic stimulus, it took longer for the individuals with tinnitus to complete sections 4 and 5, and the control group to complete sections 3, 4 and 5 in SCWT in comparison with the lack of acoustic stimulus.

CONCLUSION

It was determined that SCWT performance of the individuals with tinnitus was worse than the individuals without tinnitus, both in the presence of and without acoustic stimulus. It was found that SCWT performances of both groups with acoustic stimulus were better than their test performances without acoustic stimulus.

The potential interruptive effect of tinnitus-related distress on attention

The mechanism through which tinnitus affects attention is unclear. This study examines whether distress mediates the relationship(s) between tinnitus and sustained, selective and executive attentions as well as response inhibition. Eighteen participants with tinnitus and fifteen controls completed the Counting Stroop, Vigilance and Stop Signal tasks. Tinnitus distress was assessed using the Tinnitus Questionnaire (TQ), severity of depressive mood states examined using the Beck Depression Inventory-II, and general distress assessed using the Hospital Anxiety and Depression Scale. Tinnitus participants had significantly slower reactions during the Vigilance task (F = 4.86, p = .035), and incongruent trials of the Cognitive Counting task (F = 3.45, p = .045) compared to controls. Tinnitus-related distress significantly mediated the effect of tinnitus in incongruent trials (TQ: Sobel test t = 1.73, p = .042) of the Cognitive Counting Task. Complaints of distress and concentration difficulties are common amongst tinnitus patients in clinical settings and these afflictions have been shown to negatively impact an individual’s quality of life. If confirmed in future studies, results suggest that distress may be an important factor in the causal mechanism between tinnitus and attention.

Auditory attention in individuals with tinnitus

Introduction

Tinnitus is characterized by the presence of a sound in the absence of external sound stimulus. In individuals with normal audiometry, it may be associated with auditory attention difficulty, especially in those who report high tinnitus annoyance.

Objective

To investigate auditory attention ability in individuals with tinnitus complaint.

Methods

Cross-sectional analytical observational study. We evaluated 30 volunteers with normal hearing (up to 25 dBHL): 15 with tinnitus (test group) and 15 with no complaints (control group), aged between 18-40 years. The volunteers answered the tinnitus handicap inventory questionnaire and a visual analogue scale. Subsequently, a basic audiological evaluation (meatoscopy, tonal and vocal audiometry, and imittanciometry) and psychoacoustic measures of tinnitus (loudness and pitch) were performed. To evaluate auditory attention, the following tests were performed: auditory cognitive evoked potential (P300), central auditory processing tests (dichotic digits test and speech-in-noise test) and sustained auditory attention ability test.

Results

In the tinnitus handicap inventory, individuals with tinnitus had a mean score of 37.78 (±27.05), characterized as moderate degree. In the dichotic digits test (binaural separation), a difference was observed between the groups in both ears. Moreover, there was a difference in the speech-in-noise test in both ears (RE: p = 0.044; LE: p = 0.019), in P300 (p = 0.049) and in total sustained auditory attention ability test (p = 0.032). Also, there is a negative correlation between sustained auditory attention ability test, decrease in attentiveness and binaural integration (RE: p = 0.044; LE: p = 0.048).

Conclusions

Individuals with tinnitus had a poorer performance compared to the control group regarding auditory attention ability. Therefore, it is inferred that tinnitus is associated with poor performance in selective and sustained auditory attention in the assessed volunteers. These aspects should be considered for the management of patients with tinnitus.