The purpose of this thesis was to develop novel ways to study tinnitus, to investigate the course of tinnitus, and to study the effects of cognitive-behaviour therapy on tinnitus related distress. Data from 377 tinnitus patients were collected. A group of 216 patients completed audiological measures and were assessed in a structured interview. The Klockhoff and Lindblom's grading system was used and its inter-rater reliability assessed in a subsample showing a high degree of correspondence. A discriminant analysis showed that a substantial proportion of patients could be correctly classified into grade II or III, by measures of pitch, minimal masking level of tinnitus, avoidance of situations because of tinnitus, and tolerance in relation to onset. Using tests developed in cognitive psychology, it was found that tinnitus patients had impaired performance. There was no evidence for an attentional bias towards tinnitus related words using a computerized emotional Stroop task, but masking sounds of an "on-and-off" character were more disruptive than constant masking when patients performed the digit-symbol test. It is suggested that tinnitus distress may be increased by the 'changing-state' character of the tinnitus signal, or alternatively by intermittent masking sounds. In a case-study a patient received an i.v. injection of lidocaine while Positron Emission Tomograpy was conducted. The brain activity associated with tinnitus included the left primary, secondary and integrative auditory brain areas, as well as right paralimbic areas related to negative feelings. The precuneus (Brodmann area 7) might be a brain area involved in the aversiveness associated with tinnitus. Using a tinnitus questionnaire as the dependent measure it was found that tinnitus maskability at admission predicted distress at follow-up for an average of five years following admission. Some improvement in tinnitus occurred over time, but this was more evident in patients who had received a cognitive-behavioural treatment program. The effect of an Internet based cognitive-behavioural self-help treatment program for tinnitus was investigated showing a high dropout rate, but with positive results in that the treated patients improved.

No description available.

This Thesis attempted to first replicate the work of Andersson et al. (2000) to identify possible cognitive decrements in tinnitus sufferers. In addition, a number of trait variables were measured in comparison to a matched control group. It was discovered that the tinnitus population did not differ in terms of any trait, yet still performed worse on a number of cognitive tasks - performing as accurately, but significantly more slowly. It was thus concluded that the presence of the tinnitus interfered with cognition by consuming valuable and finite attentional resources. A second study attempted to narrow this down further, identifying specific tasks and specific circumstances in which tinnitus sufferers performed less effectively than their non-tinnitus counterparts. From these results, it was postulated that the relationship between tinnitus severity and cognitive performance is moderated by demand and as such, a longitudinal diary study (six weeks) was undertaken to measure (self-rated) effectiveness under a wide range of demands in real life. Moderated hierarchical regression techniques were thus able to identify situations in which mental demand levels drive the relationship between tinnitus and performance, thus supporting the hypothesis.

Tinnitus is the experience of sounds in the ears without any external auditory source and is a common, debilitating, chronic symptom for which we have yet to develop sufficiently efficacious interventions. Cognitive behavioral therapy (CBT) has evolved over the last 20 years to become the most empirically supported treatment for treating the adverse effects of tinnitus. Nevertheless, a significant proportion of individuals do not benefit from CBT-based treatments. In addition, the theoretical underpinnings of the CBT-model are poorly developed, the relative efficacy of isolated procedures has not yet been demonstrated, and the mechanisms of therapeutic change are largely unknown. These significant limitations preclude scientific progression and, as a consequence, leave many individuals with tinnitus suffering. To address some of these issues, a contextual multi-method, principle-focused inductive scientific strategy, based on pragmatic philosophy, was employed in the present thesis project. The overarching aim of the thesis was to explore the utility of a functional dimensional process in tinnitus: Experiential avoidance—experiential openness/acceptance (EA). EA is defined as the inclination to avoid or alter the frequency, duration, or intensity of unwanted internal sensations, including thoughts, feelings or physical sensations. The thesis is based on experimental work (Study II, VI), process and mediation studies (Study I, III, V), and on randomized controlled trials (Study III, IV). Three main sets of findings supported the utility of EA in tinnitus. First, an acceptance-based treatment (i.e.,Acceptance and Commitment Therapy, ACT) was found to be effective in controlled trials. Study III demonstrated that face-to-face ACT was more effective than a wait-list control and a habituation-based sound therapy. Study IV showed that internet-delivered ACT was more effective than an active control condition (internet-discussion forum) and equally effective as an established internet-delivered CBT treatment. Second, processes research (Study I, III, V) showed that key postulated processes of change were linked to the specific technology of ACT and that these changes in processes were associated with therapeutic outcomes. Specifically, Study V found evidence to that decreases in suppression of thoughts and feelings over the course of treatment were uniquely associated with therapeutic gains in ACT as compared with CBT. Third, experimental manipulations of experiential avoidance and acceptance processes provided support to the underlying dimension (Study II, VI). That is, Study II, employing an experimental manipulation, found that controlling background sounds were associated with reduced cognitive efficiency and increased tinnitus interference over repeated experimental trials. In addition, in normal hearing participants, experimentally induced mindfulness counteracted reduced persistence in a mentally challenging task in the presence of a tinnitus-like sound stemming from initial effortful suppression of the same sound (Study VI). It is concluded that a principle-, contextual-focused approach to treatment development may represent an efficient strategy for scientific progression in the field of psychological treatments of tinnitus severity. / Tinnitus är upplevelsen av ljud i frånvaro av en extern ljudkälla och är ett vanligt, långvarigt och svårbehandlat hälsotillstånd. Kognitiv beteendeterapi (KBT) har det starkaste forskningsstödet för att behandla de negativa konsekvenserna av tinnitus. Detta till trots svarar inte en stor andel på KBT-baserade behandlingar för tinnitus. Behandlingsutvecklingen av KBT försvåras som konsekvens av att teorier som behandlingen vilar på är dåligt utvecklade, effekten av isolerade tekniker har inte bevisats, och att förändringsmekanismer är till största del okända. Föreliggande avhandling avsåg att adressera några av ovanstående problem genom att tillämpa en induktiv, flermetod, principstyrd vetenskaplig strategi baserad på pragmatisk kontextuell filosofi. Det övergripande syftet med avhandlingen var att undersöka användbarheten i en funktionell processdimension vid tinnitus: upplevelsemässigt undvikande—upplevelsemässig acceptans (EA). EA definieras som benägenheten att undvika eller förändra frekvensen, durationen eller intensiteten av icke-önskade inre sensationer som tankar, känslor och fysiologiska sensationer. Avhandlingen är baserad på experimentella studier (Studie II, VI), process och mediationsstudier (Studie I, III, V) och randomiserade kontrollerade studier (Studie III, IV). Tre övergripande fynd bekräftade användbarheten av EA vid tinnitus. För det första kunde det påvisas i randomiserade, kontrollerade studier att en acceptans-baserad behandling (Acceptance and Commitment Therapy, ACT) hade effekt på tinnitusbesvär. Studie III fann stöd för att ACT var mer effektiv än en väntelistekontroll och en habitueringsfokuserad ljudterapi. Studie IV fann stöd för att internet-förmedlad ACT var mer effektiv än en aktiv kontrollbetingelse (internet-diskussionsforum) och lika effektiv som en etablerad internet-förmedlad KBT-behandling. För det andra kunde processforskning (Studie I, III, V) påvisa att teoretiskt viktiga processer var relaterade till specifika tekniker i ACT och att dessa processer var i sin tur associerade med behandlingsutfall. Exempelvis kunde Studie V styrka att minskning i individers benägenhet att tränga undan tankar och känslor i relation till tinnitus var unikt associerat med behandlingsutfall i ACT i jämfört med KBT. För det tredje påvisade experimentella manipulationer av acceptans- och undvikande-processer användbarheten av EA (Studie II, VI). Studie II fann stöd för att kontroll över maskeringsljud var associerad med minskad kognitiv prestationsförmåga och ökade besvära av tinnitus över upprepade experimentella manipulationer i jämfört med att inte ha kontroll över maskeringsljudet. Slutligen visade Studie VI att bland normalhörande kunde experimentellt inducerad mindfulness motverka minskad förmåga att hålla ut i en mentalt krävande uppgift i närvaro av ett tinnitusliknande ljud till följd av initial suppression av samma ljud. Den övergripande konklusionen av vetenskapliga arbeten som sammanfattas i avhandlingen var att en principstyrd och kontextuell vetenskaplig strategi kan vara en framkomlig väg för att utveckla psykologiska behandlingar för tinnitusbesvär.

This thesis presents designs of portable medical instruments to diagnose human tinnitus. At the present time, portable medical instruments are used everywhere for almost all kinds of daily health needs. Those high-performance instruments are used in medical facilities, hospitals, and clinics, and on the personal use level, as patients need them. Nowadays the digital means to design those instruments have become very important, and it's our goal to make use of the technology to upgrade and make those designs fast, accurate, easy to use, and inexpensive, so all people with need of those devices will be able to obtain them. At this time, there are many questions regarding tinnitus, but few definitive answers. Since it is still not fully understood, many comprehensive studies and analysis were carried out to present a complete model for the instruments.

No description available.

Tinnitus is the phantom perception of sound. For some people tinnitus can have a detrimental impact on their quality of life. Negative emotional feelings associated with tinnitus play a major role in enhancing and maintaining its continued presence. Despite its high prevalence across the world, its neurophysiological underpinnings remain elusive and there is no universal cure. This thesis utilises data derived from an open-label, non-randomised clinical trial whose original aim was to evaluate the effect of hearing aids for hearing-impaired individuals with tinnitus. To achieve this, a range of patient-reported clinical measures, as well as functional magnetic resonance imaging (fMRI) were used to identify both clinical and neurophysiological markers of treatment-related change over a six-month period. Evidence for clinical impact of hearing aid provision in the management of tinnitus was examined. In study 1, tinnitus handicap was compared amongst two groups of chronic tinnitus patients; those opting for hearing aids (n=42) and age-matched controls who were not (n=14). A small statistically significant reduction in tinnitus handicap as measured by the Tinnitus Handicap Questionnaire was observed in the hearing aid group six months post-fitting compared to controls. However this was not clinically significant. Given the lack of evidence for strong clinical benefit, three further investigations were conducted to identify objective neurophysiological markers associated with the presence of tinnitus. These used baseline fMRI data (i.e. prior to any hearing aid provision) derived from the same age and hearing-matched groups (chronic tinnitus, n=12 and no tinnitus controls, n=11). Independent Component Analysis, region of interest analysis and Patel’s conditional dependence measures were used to investigate resting-state brain activity across the auditory network (study 2) and within the amygdala (study 3). Neither study found any between-group differences. Study 4 examined sound-evoked differences between groups by measuring the amygdala response to emotionally evocative soundscapes using a general linear model approach. Soundscapes rated as very pleasant or very unpleasant elicited stronger amygdala activity than neutral soundscapes (replicating a previous finding). However, activity in the tinnitus group was reduced compared to controls, contrary to our expectations. While results demonstrate that the objective quantification of tinnitus is possible, this nevertheless remains a challenging field. The investigation of resting-state and sound-evoked fMRI data derived from the same participant groups illustrates how neurophysiological markers of tinnitus may only become apparent given the right choice of experimental paradigm. The identification of a potential tinnitus-related biomarker in limbic, not auditory, brain regions leads us to speculate that functional imaging may be more sensitive to the emotional consequences of the tinnitus than the neural signature of the sound perception itself. Challenges and recommendations for future tinnitus research are identified.

Melatonin, a hormone produced by the pineal gland, may be a promising treatment option for tinnitus. The primary functions of this hormone are believed to be the initiation and maintenance of sleep because its secretions coincide with circadian rhythms. Some investigators have noted that melatonin may alleviate subjective symptoms of tinnitus. Moreover, melatonin may have properties protective against ototoxic drugs such as amikacin, gentamicin, or cancer therapeutic agents that are dose dependent. In vitro, melatonin has demonstrated antioxidative properties and it has been postulated that these antioxidative properties contribute to the alleviation of tinnitus. Melatonin levels used to obtain these findings in vitro, however, are at supraphysiologic levels; therefore, it is more likely that the benefits from taking supplemental melatonin occur from minimal antioxidative properties, sleep enhancement, or other potential methods of action that are not yet understood. Melatonin offers minimal risk of toxicity with modest daily doses such as 1 to 3 mg, aswell as a low cost and favorable adverse effect profile for older adults. In addition to potential benefits in the treatment of tinnitus, melatonin also may have beneficial neurogenerative properties. We recommend that melatonin be considered for use in patients with significant tinnitus.

No description available.

No description available.