The positive side of living with tinnitus: a cross-sectional study.

OBJECTIVE: The aim of the current study was to examine the presence of positive experiences reported by individuals with tinnitus in the United States. DESIGN: The study used a cross-sectional survey design. The data were analysed using qualitative (content analysis) and quantitative (t-test or Chi-square test) analyses. STUDY SAMPLE: Study participants were individuals participating in clinical trials involving Internet-based cognitive behavioural therapy (ICBT) for tinnitus. A total of 439 respondents, 211 (48.1%) male and 228 (51.9%) female responded, and data were collected via an online questionnaire. RESULTS: Of the 439 participants, 164 (i.e. 37.4%) reported at least one positive experience. Younger participants and those with lower hearing disability were more likely to report positive experiences. The responses were categorised into six categories: Outlook (n = 139), Personal development (n = 42), Treatment-related (n = 42), Coping (n = 29), Support (n = 19), and Disease-specific (n = 19). CONCLUSIONS: The ability of individuals with chronic tinnitus to identify positive experiences may give insights regarding acceptance and coping with tinnitus as well as the temperament of individuals reporting positive experiences. Considering these variables may help when planning individualised rehabilitation programs.

COVID-19 and tinnitus: an initiative to improve tinnitus care.

OBJECTIVE: To investigate the effects of COVID-19 on individuals with tinnitus and their views to guide future tinnitus care. DESIGN: A mixed-methods cross-sectional research design. STUDY SAMPLE: An online survey was completed by 365 individuals with tinnitus from Australia and other countries. RESULTS: Tinnitus was reported to be more bothersome during the pandemic by 36% of respondents, whereas 59% reported no change and 5% reported less bothersome tinnitus. Nearly half of the respondents had received COVID-19 vaccination(s) and 12% of them reported more bothersome tinnitus while 2% developed tinnitus post-vaccination. Australian respondents spent less time in self-isolation or quarantine and saw fewer change in in-person social contact than respondents from other countries. More than 70% of respondents thought that tinnitus care services were insufficient both before and during the pandemic. Regarding their opinions on how to improve tinnitus care in the future, five themes including alleviation of condition, government policies, reduced barriers, self- and public-awareness, and hearing devices were identified. CONCLUSIONS: A majority of respondents did not perceive any change in tinnitus perception and one-third of respondents had worsened tinnitus during the pandemic. To improve tinnitus care, better awareness and more accessible resources and management are crucial.

Hearing more to hear less: a scoping review of hearing aids for tinnitus relief.

OBJECTIVE: As tinnitus is often associated with hearing loss, hearing aids have been proposed for tinnitus relief in literature for more than 70 years. There is a need for recent literature to be reviewed and guide decision making in tinnitus management. This scoping review aims to provide an update of the available evidence on hearing aids for tinnitus, focussing on the effect of sound amplification or combination devices (i.e. amplification and sound generation within one device). DESIGN: Research studies were included if they investigated hearing aids or combination devices for tinnitus and were published after 2011. STUDY SAMPLE: A total of 28 primary research studies were selected. RESULTS: Positive results of hearing aids in tinnitus patients were shown in 68% of the studies, whereas 14% demonstrated no change in tinnitus distress. However, the quality of the evidence across studies was variable. CONCLUSIONS: Scientific support for hearing aids and combination devices for tinnitus relief was found. The standalone effect of sound amplification and the added value of sound generators and adjustment of sound processing strategies needs further investigation. Stronger methodology in future studies is needed to reach consensus on how to optimise hearing solutions in a multidisciplinary approach.

Survey of tinnitus patients' acceptance of high-definition transcranial direct current stimulation as a management option.

OBJECTIVES: To investigate acceptance of high-definition transcranial direct current stimulation (HD-tDCS) as a management option for tinnitus. DESIGN: Participants completed an online version of the Tinnitus Functional Index (TFI), after which they recorded their satisfaction ratings with different hypothetical intervention outcomes on a 10-point rating scale using Opinio survey software. STUDY SAMPLE: Data from 272 tinnitus sufferers from English-speaking regions worldwide were collected, of which the majority had moderate to severe tinnitus as per TFI. RESULTS: The survey showed that HD-tDCS was considered an acceptable form of tinnitus management, and that the satisfaction rating depended significantly on a number of factors: (1) the strength of the tinnitus reduction following the intervention (p < 0.001); 2) the duration of the intervention (p < 0.001); and (3) the effects of the intervention on either tinnitus loudness or tinnitus-related distress (p < 0.001). Respondents rated their satisfaction with the intervention 10/10 only if it completely eliminated tinnitus loudness, although reductions of 50-80% were also rated highly acceptable. No association was found between tinnitus severity and acceptability ratings. CONCLUSIONS: These findings are important for future HD-tDCS trials for tinnitus, as they demonstrate the need to optimise stimulation protocols to increase effect sizes and decrease time spent on the treatment.

High-definition transcranial direct current stimulation of the dorsolateral prefrontal cortex for tinnitus modulation: a preliminary trial.

Tinnitus is the perception of sound in the absence of its external source. Non-invasive neuromodulation techniques have been used in the past decade to investigate the impact of stimulation on tinnitus perception. The objective is to invest the impact of high-definition transcranial direct current stimulation (HD-tDCS) of dorsolateral prefrontal cortex (DLPFC) stimulation on tinnitus loudness and annoyance. Thirteen participants underwent two sessions of HD-tDCS (real and sham) in a double blind, sham controlled, randomized trial. The washout period between the real and sham stimulation session was 1 week. Tinnitus loudness and annoyance was measured using a ten-point tinnitus loudness/annoyance numeric rating scale at the baseline, after 5, 10, 15 and 20 min of stimulation. There was a significant reduction in the tinnitus loudness after the HD-tDCS of DLPFC. A comparison of the different time points (5, 10, 15 and 20 min) with the baseline measurement for tinnitus loudness showed a statistically significant reduction after 15 min (t = 1.82, p = 0.047) and 20 min (t = 1.82, p = 0.047) of stimulation using the real HD-tDCS; this effect was not observed for tinnitus annoyance. HD-tDCS of DLPFC is a safe technique for tinnitus modulation. The most common transient sensations experienced during HD-tDCS were tingling, sleepiness and scalp pain. HD-tDCS of DLPFC resulted in transient tinnitus loudness suppression after 15 min of stimulation. We propose the optimum stimulation duration for HD-tDCS of DLPFC for tinnitus suppression to be 15 min instead of 20 min.

The relationship between tinnitus pitch and hearing sensitivity.

Tinnitus is the phantom perception of sounds. No single theory explaining the cause of tinnitus enjoys universal acceptance, however, it is usually associated with hearing loss. The aim of this study was to investigate the relationship between tinnitus pitch and audiometry, minimum masking levels (MML), tinnitus loudness, and distortion product otoacoustic emissions (DPOAE). This was a retrospective analysis of participant's records from the University of Auckland Hearing and Tinnitus Clinic database. The sample consisted of 192 participants with chronic tinnitus (more than 18 months) who had comprehensive tinnitus assessment from March 2008 to January 2011. There were 116 males (mean = 56.5 years, SD = 12.96) and 76 females (mean = 58.7 years, SD = 13.88). Seventy-six percent of participants had a tinnitus pitch ≥8 kHz. Tinnitus pitch was most often matched to frequencies at which hearing threshold was 40-60 (T50) dBHL. There was a weak but statistically significant positive correlation between tinnitus pitch and T50 (r = 0.15 at p < 0.05). No correlation was found between tinnitus pitch and DPOAEs, MML, audiometric edge and worst threshold. The strongest audiometric predictor for tinnitus pitch was the frequency at which threshold was approximately 50 dBHL. We postulate that this may be due to a change from primarily outer hair cell damage to lesions including inner hair cells at these levels of hearing loss.

Prescription of hearing-aid output for tinnitus relief.

OBJECTIVE: Tinnitus is a perceived sound that cannot be attributed to an external source. This study attempts to identify a prescription of amplification that is optimized as a first-fit setting for tinnitus relief. DESIGN: Participants compared the effect of high frequency amplification on their tinnitus. Stimuli were 13 speech files with different amounts of high frequency amplification (three cut-off frequencies and four gain settings) to simulate the effects of a change in DSL(I/O) v5.0 prescription in the high frequencies. STUDY SAMPLE: Twenty-five participants with chronic tinnitus participated in the study. RESULTS: A 6-dB reduction to prescribed gain at 2 kHz emerged as the most preferred output (26.47% participants) to interfere with participants' tinnitus. Overall, 70.58% of the participants' preferred a 3 to 6 dB reduction in output while 29.42% preferred a similar increase across all cut-off frequencies. A trend was observed in which the higher the tinnitus pitch the more similar the preferred output to DSL(I/O) v5.0. CONCLUSION: DSL(I/O) v5.0 appears to be a good starting point for prescription of hearing-aid output for tinnitus management. Long-term benefits of different prescriptions for tinnitus still need to be ascertained.

Role of hearing AIDS in tinnitus intervention: a scoping review.

BACKGROUND: Tinnitus can have a devastating impact on the quality of life of the sufferer. Although the mechanisms underpinning tinnitus remain uncertain, hearing loss is often associated with its onset, and hearing aids are among the most commonly used tools for its management. PURPOSE: To conduct a scoping review to explore the role of hearing aids in tinnitus management. RESEARCH DESIGN: Scoping review based on the six-stage framework of Arksey and O'Malley (2005). STUDY SAMPLE: Relevant studies were identified using various databases (Scopus, Google Scholar, SpringerLink, and PubMed) and hand searching of journals and a reference list of articles. Out of 277 shortlisted articles, 29 studies (18 research studies and 11 reviews) were chosen for charting of data based on their abstracts. DATA COLLECTION AND ANALYSIS: Tinnitus assessment measures used in studies were recorded along with changes in their scores. Measures used in studies included the Tinnitus Handicap Inventory (THI), Tinnitus Handicap Questionnaire (THQ), Tinnitus Severity Index (TSI), Tinnitus Reaction Questionnaire (TRQ), German version of Tinnitus Questionnaire (TQ), Beck Depression Inventory (BDI), and visual analogue scale (VAS) of tinnitus intensity. Where possible Cohen's d effect size statistic was calculated. RESULTS: Although the quality of evidence for hearing aids' effect on tinnitus is not strong, the weight of evidence (17 research studies for, 1 against) suggests merit in using hearing aids for tinnitus management. CONCLUSIONS: The majority of studies reviewed support the use of hearing aids for tinnitus management. Clinicians should feel reassured that some evidence shows support for the use of hearing aids for treating tinnitus, but there is still a need for stronger methodology and randomized control trials.

Hearing Health Care Stakeholders' Perspectives on Teleaudiology Implementation: Lessons Learned During the COVID-19 Pandemic and Pathways Forward.

PURPOSE: The purpose of this study was to explore how teleaudiology is perceived by Australian-based hearing health care stakeholders (clients, clinicians, students, academics, and industry partners) to inform future teleaudiology implementation. METHOD: Five cross-sectional online surveys were adopted, and a total of 366 stakeholders responded (173 clients, 110 clinicians, 58 students, 19 academics, and six industry partners). RESULTS: Results show that 55% of clients and over 90% of clinicians, students, academics, and industry partners knew what teleaudiology was. Experience in teleaudiology appointments was shared by 85% of clinicians and 7% of clients. Moreover, 98% of clients were not offered any teleaudiology appointments. Teleaudiology apps were used by 66% of clinicians and 26% of clients. Both clients and clinicians acknowledged the benefits of teleaudiology including convenience and accessibility and identified drawbacks, such as loss of personal interaction and communication difficulty. About 80% of students and academics reported inclusion of teleaudiology within their universities' curriculum but only to a limited extent. Low teleaudiology uptake rates in placement clinics, as well as insufficient funding and staffing, were suggested as barriers to learning and teaching teleaudiology. Industry partners were generally confident in training clinicians to use teleaudiology products and teaching students on teleaudiology, but only one industry partner had been invited by universities for teaching purposes. CONCLUSIONS: Low teleaudiology use and reserved attitudes toward widespread teleaudiology implementation were observed among clients. Clinicians, students, academics, and industry partners generally displayed positive attitudes toward teleaudiology use. Increasing awareness of teleaudiology services and collaboration between stakeholders are crucial in promoting teleaudiology uptake. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.23519292.

A protocol for the Hearing impairment in Adults: A Longitudinal Outcomes Study (HALOS).

BACKGROUND: Often considered an "invisible disability", hearing loss is one of the most prevalent chronic diseases and the third leading cause for years lived with disability worldwide. Hearing loss has substantial impacts on communication, psychological wellbeing, social connectedness, cognition, quality of life, and economic independence. The Hearing impairment in Adults: a Longitudinal Outcomes Study (HALOS) aims to evaluate the: (1) impacts of hearing devices (hearing aids and/or cochlear implants), (2) differences in timing of these interventions and in long-term outcomes between hearing aid and cochlear implant users, and (3) cost-effectiveness of early intervention for adult-onset hearing loss among hearing device users. MATERIALS AND METHODS: HALOS is a mixed-methods study collecting cross-sectional and longitudinal data on health and social outcomes from 908 hearing aid and/or cochlear implant users aged ≥40 years, recruited from hearing service providers across Australia. The quantitative component will involve an online survey at baseline (time of recruitment), 24-months, and 48-months and will collect audiological, health, psychosocial, functional and employment outcomes using validated instruments. The qualitative component will be conducted in a subset of participants at baseline and involve semi-structured interviews to understand the patient journey and perspectives on the Australian hearing service model. ETHICS: This study has been approved by the Macquarie University Human Research Ethics Committee (ID: 11262) and Southern Adelaide Local Health Network (ID: LNR/22/SAC/88). Dissemination of results: Study findings will be disseminated to participants via a one-page summary, and to the public through publications in peer-reviewed journals and presentations at conferences. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry (ANZCTR) registration number: ACTRN12622000752763.

Resting-state Networks in Tinnitus : A Scoping Review.

Chronic subjective tinnitus is the constant perception of a sound that has no physical source. Brain imaging studies show alterations in tinnitus patients' resting-state networks (RSNs). This scoping review aims to provide an overview of resting-state fMRI studies in tinnitus, and to evaluate the evidence for changes in different RSNs. A total of 29 studies were included, 26 of which found alterations in networks such as the auditory network, default mode network, attention networks, and visual network; however, there is a lack of reproducibility in the field which can be attributed to the use of different regions of interest and analytical methods per study, and tinnitus heterogeneity. Future studies should focus on replication by using the same regions of interest in their analysis of resting-state data, and by controlling adequately for potential confounds. These efforts could potentially lead to the identification of a biomarker for tinnitus in the future.

Impact of tDCS and HD-tDCS on tinnitus perception: A scoping review.

Tinnitus is the auditory phantom perception of a sound that severely affects the quality of life of over 300,000 people in the United Kingdom alone. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation tool, which has been investigated as a potential tinnitus management option since 2006. This study aimed to investigate the impact of tDCS and high-definition transcranial direct current stimulation (HD-tDCS) on tinnitus perception. A scoping review was undertaken using the framework by Arksey and O'malley (2005). After consideration of relevance, 38 primary research studies were included in the data charting to examine the impact of (HD-)tDCS on tinnitus. Twenty-two of the primary research studies reported significant therapeutic effects of (HD)-tDCS on tinnitus perception. However, only eight of these included a sham-control condition. The tDCS protocols in the studies were highly heterogeneous and sample sizes were generally small. More double-blind, sham-controlled trials are needed that use similar protocols and outcome measures before definitive conclusions about the efficacy of (HD-)tDCS for tinnitus can be drawn.

High Definition transcranial Direct Current Stimulation (HD-tDCS) for chronic tinnitus: Outcomes from a prospective longitudinal large cohort study.

BACKGROUND: Transcranial Direct Current Stimulation (tDCS) aims to induce cortical plasticity by modulating the activity of brain structures. The broad stimulation pattern, which is one of the main limitations of tDCS, can be overcome with the recently developed technique called High-Definition tDCS (HD-tDCS). OBJECTIVE: Investigation of the effect of HD-tDCS on tinnitus in a large patient cohort. METHODS: This prospective study included 117 patients with chronic, subjective, non-pulsatile tinnitus who received six sessions of anodal HD-tDCS of the right Dorsolateral Prefrontal Cortex (DLPFC). Therapy effects were assessed by use of a set of standardized tinnitus questionnaires filled out at the pre-therapy (Tpre), post-therapy (T3w) and follow-up visit (T10w). Besides collecting the questionnaire data, the perceived effect (i.e., self-report) was also documented at T10w. RESULTS: The Tinnitus Functional Index (TFI) and Tinnitus Questionnaire (TQ) total scores improved significantly over time (pTFI<0.01; pTQ<0.01), with the following significant post hoc comparisons: Tpre vs. T10w (pTFI<0.05; pTQ<0.05) and T3w vs. T10w (pTFI<0.01; pTQ<0.01). The percentage of patients reporting an improvement of their tinnitus at T10w was 47%. Further analysis revealed a significant effect of gender with female patients showing a larger improvement on the TFI and TQ (pTFI<0.01; pTQ<0.05). CONCLUSIONS: The current study reported the effects of HD-tDCS in a large tinnitus population. HD-tDCS of the right DLPFC resulted in a significant improvement of the tinnitus perception, with a larger improvement for the female tinnitus patients.

Tinnitus and tinnitus disorder: Theoretical and operational definitions (an international multidisciplinary proposal).

As for hypertension, chronic pain, epilepsy and other disorders with particular symptoms, a commonly accepted and unambiguous definition provides a common ground for researchers and clinicians to study and treat the problem. The WHO's ICD11 definition only mentions tinnitus as a nonspecific symptom of a hearing disorder, but not as a clinical entity in its own right, and the American Psychiatric Association's DSM-V doesn't mention tinnitus at all. Here we propose that the tinnitus without and with associated suffering should be differentiated by distinct terms: "Tinnitus" for the former and "Tinnitus Disorder" for the latter. The proposed definition then becomes "Tinnitus is the conscious awareness of a tonal or composite noise for which there is no identifiable corresponding external acoustic source, which becomes Tinnitus Disorder "when associated with emotional distress, cognitive dysfunction, and/or autonomic arousal, leading to behavioural changes and functional disability.". In other words "Tinnitus" describes the auditory or sensory component, whereas "Tinnitus Disorder" reflects the auditory component and the associated suffering. Whereas acute tinnitus may be a symptom secondary to a trauma or disease, chronic tinnitus may be considered a primary disorder in its own right. If adopted, this will advance the recognition of tinnitus disorder as a primary health condition in its own right. The capacity to measure the incidence, prevalence, and impact will help in identification of human, financial, and educational needs required to address acute tinnitus as a symptom but chronic tinnitus as a disorder.

Optimization of Transcranial Direct Current Stimulation of Dorsolateral Prefrontal Cortex for Tinnitus: A Non-Linear Dose-Response Effect.

Neuromodulation is defined as the process of augmenting neuroplasticity via invasive or non-invasive methods. Tinnitus is the perception of sound in the absence of its external source. The objective of this study was to optimize the parameters of transcranial direct current stimulation (tDCS) of dorsolateral prefrontal cortex (DLPFC) for tinnitus suppression. The following factors were optimized in the dose-response design (n = 111): current intensity (1.5 mA or 2 mA), stimulation duration (20 min or 30 min), and number of stimulation sessions (2, 4, 6, 8, or 10), with a 3-4 day washout period between each session. Participants underwent a minimum of 2 sessions in 1 week or maximum of 10 sessions in 5 weeks' time. Tinnitus loudness was measured in pre-post design using a 10-point numeric rating scale. There was a significant reduction in tinnitus loudness after tDCS of DLPFC. There was no significant difference between the intensity and duration of stimulation. As the number of sessions increased, there was a higher reduction in the tinnitus loudness; however, this effect plateaued after 6 sessions.

Effects of Electrical Stimulation in Tinnitus Patients: Conventional Versus High-Definition tDCS.

BACKGROUND: Contradictory results have been reported for transcranial direct current stimulation (tDCS) as treatment for tinnitus. The recently developed high-definition tDCS (HD tDCS) uses smaller electrodes to limit the excitation to the desired brain areas. OBJECTIVE: The current study consisted of a retrospective part and a prospective part, aiming to compare 2 tDCS electrode placements and to explore effects of HD tDCS by matched pairs analyses. METHODS: Two groups of 39 patients received tDCS of the dorsolateral prefrontal cortex (DLPFC) or tDCS of the right supraorbital-left temporal area (RSO-LTA). Therapeutic effects were assessed with the tinnitus functional index (TFI), a visual analogue scale (VAS) for tinnitus loudness, and the hyperacusis questionnaire (HQ) filled out at 3 visits: pretherapy, posttherapy, and follow-up. With a new group of patients and in a similar way, the effects of HD tDCS of the right DLPFC were assessed, with the tinnitus questionnaire (TQ) and the hospital anxiety and depression scale (HADS) added. RESULTS: TFI total scores improved significantly after both tDCS and HD tDCS (DLPFC: P < .01; RSO-LTA: P < .01; HD tDCS: P = .05). In 32% of the patients, we observed a clinically significant improvement in TFI. The 2 tDCS groups and the HD tDCS group showed no differences on the evolution of outcomes over time (TFI: P = .16; HQ: P = .85; VAS: P = .20). CONCLUSIONS: TDCS and HD tDCS resulted in a clinically significant improvement in TFI in 32% of the patients, with the 3 stimulation positions having similar results. Future research should focus on long-term effects of electrical stimulation.

Intensity, Duration, and Location of High-Definition Transcranial Direct Current Stimulation for Tinnitus Relief.

BACKGROUND AND OBJECTIVE: Tinnitus is the perception of a phantom sound. The aim of this study was to compare current intensity (center anode 1 mA and 2 mA), duration (10 minutes and 20 minutes), and location (left temporoparietal area [LTA] and dorsolateral prefrontal cortex [DLPFC]) using 4 × 1 high-definition transcranial direct current stimulation (HD-tDCS) for tinnitus reduction. METHODS: Twenty-seven participants with chronic tinnitus (>2 years) and mean age of 53.5 years underwent 2 sessions of HD-tDCS of the LTA and DLPFC in a randomized order with a 1 week gap between site of stimulation. During each session, a combination of 4 different settings were used in increasing dose (1 mA, 10 minutes; 1 mA, 20 minutes; 2 mA, 10 minutes; and 2 mA, 20 minutes). The impact of different settings on tinnitus loudness and annoyance was documented. RESULTS: Twenty-one participants (77.78%) reported a minimum of 1 point reduction on tinnitus loudness or annoyance scales. There were significant changes in loudness and annoyance for duration of stimulation,F(1, 26) = 10.08,P< .005, and current intensity,F(1, 26) = 14.24,P= .001. There was no interaction between the location, intensity, and duration of stimulation. Higher intensity (2 mA) and longer duration (20 minutes) of stimulation were more effective. CONCLUSIONS: A current intensity of 2 mA for 20-minute duration was the most effective setting used for tinnitus relief. The stimulation of the LTA and DLPFC were equally effective for suppressing tinnitus loudness and annoyance.

Methodology for studying the transient effects of transcranial direct current stimulation combined with auditory residual inhibition on tinnitus.

BACKGROUND: Transcranial direct current stimulation (tDCS) and auditory residual inhibition (RI) are short lasting non-invasive techniques that can suppress tinnitus in some people. A pilot study was undertaken to evaluate methods to measure a potential additive effect of these treatments. NEW METHOD: Ten participants (mean age 59 years) with chronic tinnitus underwent four sessions of anodal tDCS of the left temporoparietal area(LTA) combined with 1min of auditory stimulation (broadband noise presented at tinnitus minimum masking level [MML]+10 dB), either before, during or immediately after tDCS and in a sham controlled session. Participants continuously monitored and recorded their MML on custom software prior to stimulation, during 20 min of tDCS, and 30 min following tDCS. A tinnitus loudness rating was undertaken before and after completion of testing. RESULTS: Nine out of ten participants completed the study, one participant dropped out after two sessions due to self-reported worsening in tinnitus symptoms. Seven out of nine participants reported transient tinnitus suppression when sound stimulation was presented along with tDCS. No reliable change in MML was observed. COMPARISON WITH EXISTING METHOD: This is the first study to examine the feasibility of continuously measuring MML while providing a combination of auditory and noninvasive brain stimulation simultaneously. CONCLUSIONS: We propose modifications in the protocol used, to find ways to increase the duration of auditory RI and investigate its underlying mechanisms. Recommendations for further research are discussed.

Modulation of Perception or Emotion? A Scoping Review of Tinnitus Neuromodulation Using Transcranial Direct Current Stimulation.

BACKGROUND: Tinnitus is the phantom perception of sound and can have negative effect on the quality of life. Transcranial direct current stimulation (tDCS) is a noninvasive neuromodulation technique, which can increase or decrease the cortical excitability in the brain region to which it is applied. tDCS has been used for tinnitus research since 2006. OBJECTIVE: To investigate whether tDCS affects tinnitus perception, related emotion, or both, and the potential implications for tinnitus management. METHODS: A scoping review was undertaken using the methods proposed by Arksey and O'Malley. After initial consideration of title relevance and reading abstracts, 15 studies were included in this review. The data from these studies were charted to investigate the impact of tDCS on tinnitus perception and emotions. RESULTS: tDCS results in transient suppression of tinnitus loudness and annoyance; however, it does not lead to long-term impact on tinnitus related emotion. Local stimulation of different sites of stimulation (left temporoparietal area, dorsolateral prefrontal cortex, and auditory cortex) might modulate tinnitus perception (loudness) and emotions differently; however, further research is needed to explore this hypothesis. This review has identified aspects of methodologies that require attention in upcoming tinnitus and tDCS trials to offer better insights. CONCLUSIONS: tDCS is an effective research tool for transient tinnitus neuromodulation. However, efforts should be invested in designing clinical trials using local and multiple sites of stimulation, optimized parameters, and objective outcome measures before it can be translated in to a clinical tool for tinnitus management.

Randomized Trial of Transcranial Direct Current Stimulation and Hearing Aids for Tinnitus Management.

Background The perception of sound in the absence of an external sound is tinnitus. Tinnitus can have a severe negative impact on quality of life. Objective This trial investigated whether multisession anodal transcranial direct current stimulation (tDCS) of the left temporoparietal area would enhance sound therapy from hearing aids. Methods Forty participants (mean age = 54 years) experiencing chronic tinnitus (minimum 2 years) completed a 7-month long double-blind randomized clinical trial. Participants were randomized into 2 groups: control receiving sham tDCS and experimental receiving tDCS. Each group underwent multisession (5 consecutive sessions with 24-hour gap) anodal tDCS (2 mA intensity and 20 minutes duration) of the left temporoparietal area, followed by hearing aid use for 6 months. The impact of tDCS and hearing aid use on tinnitus was assessed using questionnaires (primary measure: Tinnitus Functional Index) and minimum masking level measurement. Results There was a significant reduction in the overall Tinnitus Functional Index score with time, F(2, 37) = 11.9, P = .0001, for both the groups. Similar patterns were seen for secondary measures. tDCS appeared to have a positive effect on minimum masking levels but not questionnaire responses. Conclusions After 3 months of hearing aid use, there were significant improvements in tinnitus, which were sustained at 6 months of use. The hearing aid effects appeared independent of tDCS. Further investigations of tDCS or other neuromodulators priming the auditory system for sound therapy based tinnitus treatments are warranted.