Tinnitus-frequency specific activity and connectivity: A MEG study.

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

Prediction of treatment outcome in patients suffering from chronic tinnitus - from individual characteristics to early and long-term change.

BACKGROUND AND OBJECTIVE: Despite the availability of successful treatment approaches for chronic tinnitus, it has proven difficult to predict who profits from treatment and it is still an open question if it is possible at all. We tried to overcome methodological shortcomings and to predict treatment outcome indicated by questionnaires measuring tinnitus distress. METHODS: This is an observational, prospective cohort study. Lasso and post-selection inference methods were used to predict treatment outcome in patients suffering from chronic tinnitus (N = 747). Patients were treated for five consecutive days in an interdisciplinary setting according to guidelines. RESULTS: Early change, i.e. a positive response after the screening day, as well as change due to treatment was predicted by several psychopathological variables, but also tinnitus-related factors. Female gender as an example was a predictor for change due to treatment. In general, therapy success both for early change and change due to treatment cannot be predicted satisfactorily as indicated by a high mean cross-validation error (for early change: 9.83, for change due to treatment: 14.40). Analyzing sub-groups separated by tinnitus severity to reduce heterogeneity did not improve the situation and for patients with high tinnitus severity no predictors at all could be reported (cross-validated error: 11.62 for the low quartile, 13.38 for the low-medium quartile, and 15.61 for the medium-high quartile). CONCLUSION: Several psychopathological and tinnitus-related variables predicted early and long-term change. Nevertheless, also overcoming methodological shortcomings to predict treatment success did not lead to satisfactory results, but rather emphasizes the high heterogeneity of chronic tinnitus.

Improving the assessment of functional impairment in tinnitus sufferers: validation of the German version of the Tinnitus Functional Index using a confirmatory factor analysis.

OBJECTIVES: Chronic tinnitus negatively impacts daily functioning. To specifically assess this impairment, the Tinnitus Functional Index (TFI) was developed. The current study investigated the hierarchical, eight-factorial structure for the German TFI and examined its psychometric properties. DESIGN: In an online assessment, the TFI and other validated health-related measurements were completed. Confirmatory factor analysis (CFA) was conducted to investigate the factorial structure by testing two competing models: (1) a general factor model, and (2) a hierarchical second-order factor model. STUDY SAMPLE: 316 research volunteers (59.8% female) with low to moderate tinnitus distress were included. RESULTS: CFA revealed an insufficient fit of the data to the general factor model. For the hierarchical second-order factor model, an acceptable model fit was shown (χ2/df ratio = 2.74, RMSEA = 0.07, SRMR = 0.05, CFI = 0.95, TLI = 0.95). Correlational analyses between the TFI and measures assessing tinnitus distress, depression, sleeping difficulties, subjective well-being, and personality dimensions indicated high convergent and moderate discriminant validity. Internal consistency reliability was excellent. CONCLUSIONS: The results confirm the hierarchical, eight-factorial structure of the German TFI. The TFI is a promising inventory that should be used on a regular basis.HighlightsThe results of our study confirm the hierarchical eight-factorial structure of the German TFI.Confirmatory factor analysis revealed an acceptable model fit of the data.Convergent validity of the German TFI was high.Discriminant validity of the German TFI was moderate.The German TFI is a reliable questionnaire to assess tinnitus functional impairment.

Comparing pure tone and narrow band noise to measure tonal tinnitus pitch-match frequency.

Tinnitus assessment is a precursor for individualized treatment and outcome measurement. In the recent years, several studies proposed two-alternative forced choice (2AFC) recursive matching as a method to determine tinnitus pitch-match frequency in a standardized reliable manner. Currently, pure tones are used as comparison stimuli to assess pitch-match frequency. In this study, we investigated the psychometric quality of the method comparing different sound types. We measured 20 chronic tinnitus patients in 2 runs on 3 days. To assess pitch-match frequency, we used 2AFC recursive matching and compared results between pure tones and narrow band noise (NBN). Test-retest reliability between runs and across sound types was high (α>0.9) and increased across days. Perceived matching difficulty and time to completion decreased over repetitions. Importantly, the difference of matched frequencies (DMF) between runs was significantly less for NBN. When patients matched the spectral bandwidth of a test tone to their tinnitus, consistency was high (α=0.86) and no patient indicated continuously a pure tone. In conclusion, we recommend using NBN sounds in 2AFC recursive matching to assess pitch-match frequency as a standardized reliable method. Such a procedure could be offered as smartphone-based application to monitor tinnitus symptomatology for individualized assessment and treatment outcome.

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.

One Step Closer towards a Reliable Tinnitus Pitch-Match Frequency Determination Using Repetitive Recursive Matching.

INTRODUCTION: The determination of the tinnitus pitch-match (PM) frequency is not straightforward but an important audiological assessment recommended for clinical and research purposes. We evaluated repetitive recursive matching using an iPod-based matching procedure as a method to estimate a patient's PM frequency without audiometric equipment. METHODS: One hundred and seventeen patients with chronic tonal tinnitus (uni- and bilateral tinnitus) measured their tinnitus in 10 sessions using a self-administered automated iPod-based procedure comprising a recursive 2 interval forced-choice test. RESULTS: Mean SD of the PM frequency of all participants across sessions was 0.41 octaves. The internal consistency measured by Cronbach's α was very high (0.8->0.95). As an example, 7 PMs obtained excellent internal consistency (α = 0.93). The exclusion of the first and/or second session led to more definite PMs with a decreased SD. Outliers were identified by PMs departing 2 SDs (i.e., 0.94 octaves) from the mean variability (n = 5). CONCLUSION: Repetitive recursive matching together with recommendations for the exclusion of initial and redundant sessions as well as outlier identification and treatment can enable a reliable estimation of the PM frequency.

Psychometric assessment of mental health in tinnitus patients, depressive and healthy controls.

Tinnitus describes the perception of a sound without external source and is characterized by high comorbidity, e.g. depression. In many studies, tinnitus patients were compared to healthy controls while a comorbid psychiatric diagnosis was an exclusion criterion. Consequently, patients with severe tinnitus and psychiatric comorbidity were often neglected. In the current study, we tried to fill this gap and compared four groups including two control groups: (1) chronic tinnitus patients with mild tinnitus distress (N = 37), (2) chronic tinnitus patients with severe tinnitus distress (N = 24), (3) patients suffering from depression, but no tinnitus (major depressive disorder, MDD; N = 23) and (4) healthy controls (N = 42). We assessed their clinical profile with clinical questionnaires concerning anxiety, depression and somatoform symptoms. Data were analyzed with a canonical discriminant analysis resulting in two factors. Factor 1 was called general psychopathology, because most questionnaires loaded highly on it. Regarding this factor, patients with severe tinnitus distress and MDD controls were impaired equally strong. Patients with mild tinnitus distress were more strongly affected than healthy controls. Both tinnitus groups reached higher values than the two control groups with regard to factor 2, called somatization. These results stress the presence of significant general psychopathology even in mild tinnitus.

Chronic tinnitus and the limbic system: Reappraising brain structural effects of distress and affective symptoms.

Chronic tinnitus has been associated with brain structural changes in both the auditory system as well as limbic system. While there is considerable inconsistency across brain structural findings, growing evidence suggests that distress and other non-auditory symptoms modulate effects. In this study we addressed this issue, testing the hypothesis that limbic changes in tinnitus relate to both disease-related distress as well as co-morbid psychopathology. We obtained high-resolution structural magnetic resonance imaging (MRI) scans from a total of 125 subjects: 59 patients with bilateral chronic tinnitus (29 with a co-morbid psychiatric condition, 30 without), 40 healthy controls and 26 psychiatric controls with depression/anxiety disorders (without tinnitus). Voxel-based morphometry with the CAT12 software package was used to analyse data. First, we analysed data based on a 2 × 2 factorial design (tinnitus; psychiatric co-morbidity), showing trend-level effects for tinnitus in ROI analyses of the anterior cingulate cortex and superior/transverse temporal gyri, and for voxel-based analysis in the left parahippocampal cortex. Multiple regression analyses showed that the parahippocampal finding was mostly predicted by tinnitus rather than (dimensional) psychopathology ratings. Comparing only low-distress tinnitus patients (independent of co-morbid conditions) with healthy controls also showed reduced left parahippocampal grey matter. Our findings demonstrate that depression and anxiety (not only subjective distress) are major modulators of brain structural effects in tinnitus, calling for a stronger consideration of psychopathology in future neurobiological and clinical studies of tinnitus.

Impairments of Speech Comprehension in Patients with Tinnitus-A Review.

Tinnitus describes the subjective perception of a sound despite the absence of external stimulation. Being a sensory symptom the majority of studies focusses on the auditory pathway. In the recent years, a series of studies suggested a crucial involvement of the limbic system in the manifestation and development of chronic tinnitus. Regarding cognitive symptoms, several reviews addressed the presence of cognitive impairments in tinnitus as well and concluded that attention and memory processes are affected. Despite the importance for social communication and the reliance on a highly functional auditory system, speech comprehension remains a largely neglected field in tinnitus research. This is why we review here the existing literature on speech and language functions in tinnitus patients. Reviewed studies suggest that speech comprehension is impaired in patients with tinnitus, especially in the presence of competing noise. This is even the case in tinnitus patients with normal hearing thresholds. Additionally, speech comprehension measures seem independent of other measures such as tinnitus severity and perceived tinnitus loudness. According to the majority of authors, the speech comprehension difficulties arise as a result of central processes or dysfunctional neuroplasticity.

Results of an Interdisciplinary Day Care Approach for Chronic Tinnitus Treatment: A Prospective Study Introducing the Jena Interdisciplinary Treatment for Tinnitus.

Objective: Considering the heterogeneity of the symptoms shown by patients suffering from chronic tinnitus, there are surprisingly few interdisciplinary treatments available, and mostly available only for inpatients. In order to provide an interdisciplinary treatment, we developed a day care concept in which each patient was treated by an ENT doctor, a cognitive behavioral therapist, a specialist for medical rehabilitation and an audiologist (Jena Interdisciplinary Treatment for Tinnitus, JITT). The aim of this study was to observe the changes of tinnitus related distress due to interdisciplinary day care treatment and to determine which factors mediate this change. Subjects and Methods: Tinnitus annoyance was measured using the Tinnitus Questionnaire on 308 patients with chronic tinnitus. They were treated in the day care unit over five consecutive days between July 2013 and December 2014. Data were collected before treatment when screened (T0), at the beginning (T1) and at the end of the 5 day treatment (T2), as well as 20 days (T3) and 6 months after treatment (T4). Results: Overall, tinnitus annoyance improved significantly from the screening day to the beginning of treatment, and to a much larger degree from the beginning to the end of treatment. The treatment outcome remained stable 6 months after treatment. Patients with the following symptoms displayed higher tinnitus annoyance at T0: dizziness at tinnitus onset, tinnitus sound could not be masked with background noise, tinnitus worsening during physical stress, comorbid psychiatric diagnosis, higher age and higher hearing loss. Loudness of tinnitus perceived in the right ear correlated with tinnitus annoyance significantly. Demographic, tinnitus and strain variables could only explain 12.8% of the variance of the change in tinnitus annoyance from T0 to T4. Out of 39 predictors, the only significant ones were "sick leave 6 months before treatment" and "tinnitus annoyance at T0." Conclusion: The newly developed JITT represents a valuable treatment for chronic tinnitus patients with improvement remaining stable for at least 6 months after treatment. Using a large number of variables did not allow predicting treatment outcome which underlines the heterogeneity of tinnitus.