Introduction: This work explored the concept of ‘empowerment’ in health care. A concept map of ‘empowerment’ was generated based on theories of linguistic analysis to locate aspects of empowerment in conversational data. The process of empowerment was understood within the theory of transformative learning as ‘perspective change’. A ten phase model of the transformative learning process was used to provide evidence of perspective transformation. The empowerment process was explored through the delivery of the intervention Video Interaction Guidance to 16 hearing families of pre-lingual deaf children. Methods: The parents of the deaf children and the intervention guide engaged in conversations reviewing video clips of the parent and child in interaction. These conversations were processed through a corpus analysis software programme to discern key extracts of the participants’ conversational data. These extracts were to subject to discourse analysis to find evidence of transformative learning. Analysis: Transformative learning was observed in 10 families. Transcript extracts representing the model of transformative learning were variable. Principles of conversation analysis were applied to explore the learning process in interaction. Participant speech was tagged to assess their level of engagement. Outcomes: The corpus analysis-driven tagging process offers an original approach to representing the key content of large sets of interview data but in this work, was limited in showing how the interaction created opportunities for learning. Transformative learning processes were variable and the ten phase model could not be characterised in terms of discourse features alone. The intervention encouraged critical reflection but warrants directed focus to achieve learning. The participants were effective in acting as co-collaborators in the intervention process. Discussion and concluding remarks: Models of empowerment must focus on the process, of the ways in which the guide and the participant create learning opportunities and evidence of this must be multimodal. Patient-centred interventions should be supported by an open, communicative relationship with the health service provider.

Otitis Media with Effusion (OME) is a common childhood condition leading to hearing loss, and its treatment with ventilation tubes (VTs) is one of the commonest surgical procedures. However, aetiology of OME is poorly understood, and its current treatment requires improvement as OME frequently recurs once VTs extrude. The first, clinical part of this thesis showed that 63.6% of children randomised to VT insertion in a clinical trial will require VTs again, and even with additional adenoidectomy the need for repeat surgery remains high. Although published national guidelines set out criteria for surgery, the multicentre study presented here showed that only 32.2% of children that had VTs met these criteria, and guidelines' publication had limited impact on clinical practice. The second, laboratory part of this thesis demonstrated the importance that bacteria and biofilms play in aetiology of OME, as live bacteria were demonstrated in 91.9% of middle ear effusions (using culture and confocal microscopy). Following from this, a Staphylococcus aureus biofilm model was developed, and used to show that biofilm eradication requires antibiotic (rifampicin and lindamycin) levels 1,000 times higher than those required to inhibit planktonic bacteria, over a period of 2-3 weeks. To achieve this in the middle ear, a local delivery strategy using biodegradable poly (Iactic-coglycolic acid) antibiotic pellets was proposed. Drug release from these pellets was investigated with High Performance Liquid Chromatography and Serial Plate Transfer Testing, which demonstrated that antibiotics can be released for up to 3 weeks. Importantly, the pellets were able to eradicate biofilms in the in vitro model. This thesis has shown that current OME treatment has significant deficiencies, but better understanding of OME pathogenesis raises the possibility of rational new therapeutic strategies. Biodegradable antibiotic pellets designed to eradicate OME biofilms may be a better future treatment that could improve the lives of countless children.

Spatial attention is an essential mechanism that helps us perceive our surroundings by bringing into consciousness environmental occurrences or objects that may be of importance. Studies of spatial attention have classically recorded behavioural responses to targets presented in a region of space where attention had previously been allocated to. Such investigations show a behavioural facilitation at the same location due to cueing, but less in known about the effects of shifts of attention when the cued location is not the location of interest. This thesis presents seven experiments aimed at investigating this by implementing and revising the attentional repulsion effect (ARE). The ARE is a perceptual localisation error when attention is diverted from the region of interest and it has been extensively studied in the visual domain, however, the rising number of ARE studies has created numerous research methodologies used to evoke the effect, which may have led to isolated reports. This thesis attempts to combine past methodologies with a new approach to quantify the effect, and will address some methodological differences evident in the literature, in order to optimise the stimulus paradigms and maximise the effect. The results show that a robust ARE can be elicited in the visual modality, but the same is not observed in the auditory modality. Furthermore, when using cues that are of different modality than the targets, the ARE is only observed in the visual target modality. Using visual cues and auditory targets will produce an attraction effect, in line with the ventriloquism theory. However, the implementation of interstimuli intervals up to 1.5 seconds would be enough to disrupt the ventriloquism illusion, but it did not alter the resulted attraction. Lastly, one question regarding the role of attention in sensory adaptation was addressed. I hypothesise that sensory adaptation could be further a contributor to the ARE given that most psychophysics paradigms of the ARE repeat the same stimuli thousands of times, uninterruptedly. The results are inconclusive mainly due to experimental design. All results are discussed in relation with theories of spatial and multimodal attention.

Hearing loss is a widespread condition that can substantially affect not only auditory functioning but also social functioning. Therefore, it is essential to demonstrate that auditory rehabilitation can improve social participation in individuals with hearing loss. However, currently, there is a lack of agreed-upon, gold-standard, hearing-specific outcome measures. Consequently, the primary aim of this research was to develop a high quality measure of hearing-related social participation restrictions for use in research and practice. To achieve this aim, four consecutive studies were carried out using best practice questionnaire design techniques. Study 1 generated content for the Social Participation Restrictions Questionnaire (SPaRQ) through semi-structured interviews with 25 adults with hearing loss and nine hearing healthcare professionals. Study 2 evaluated the content of the measure through a subject matter expert panel with 20 hearing healthcare professionals and cognitive interviews with 14 adults with hearing loss. Study 3 assessed the psychometric properties of the SPaRQ by applying Rasch analysis to data collected from 279 adults with hearing loss. Finally, Study 4 further assessed the psychometric properties of the SPaRQ by applying traditional psychometric analysis to data collected from a further 102 adults with hearing loss. This research led to the development of a 19-item questionnaire that measured two key elements: social behaviours (e.g. difficulties with social interactions) and social perceptions (e.g. feelings of isolation). There was strong evidence to support the measurement properties of SPaRQ, including construct validity, person separation reliability, and internal consistency. Furthermore, the response scale was statistically justified and respondent burden was minimal. Future research should examine additional measurement properties, such as responsiveness and cross-cultural validity. Also, the best practice techniques used in this research should be applied to other new and existing hearing-specific questionnaires to ensure that they meet the requisite standards for use in clinical trials and clinical practice.

No description available.

No description available.

Thesis (B.Sc)--University of Hong Kong, 2005. / "A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2005." Also available in print.

While cochlear implants (CIs) have transformed the lives of hundreds of thousands of profoundly deaf individuals worldwide, the ability of individual patients to understand speech through their CI varies widely. The longitudinal study reported in this thesis aimed to investigate the role of cortical function and plasticity in helping to predict and explain variability in individual CI outcome. Speech-evoked cortical activations, measured using functional near-infrared spectroscopy (fNIRS), and behavioural measures of speech perception were acquired in adult CI recipients before implantation through to six months after CI activation. As anticipated, cochlear implantation enabled the significant recovery of auditory speech perception over the first six months of CI use, yet individual performance varied widely across CI users. fNIRS enabled the measurement of speech-evoked cortical activations from bilateral superior temporal cortex (STC) that were free from CI-generated artefacts. Cortical activation to visual speech measured before implantation was able to significantly predict future CI outcome measured following six months of CI use. This pre-implant measure of brain activity provided unique predictive value above that of well-established clinical characteristics, including the age-at-onset and duration of deafness. When examining changes in cortical activation from before to after implantation, a greater increase in STC activation to visual speech was found to be related to better CI outcome. These visual-related changes also predicted changes in STC activation to auditory speech. These results highlight the importance of visual speech cues and coupling between the auditory and visual modalities during the recovery of auditory function with a CI. Together, the findings demonstrate the potential of fNIRS as a brain-imaging tool that is uniquely well-suited for use in cochlear implantation. Future applications of this technology could help to explain individual variability in CI success and to deliver more accurate clinical prognoses for CI candidates.

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.

The Tinnitus Functional Index (TFI) was developed in the USA as a standard for assessing the functional impact of tinnitus based on eight tinnitus-related domains. The finalised 25-item version was never formally validated. This PhD seeks to assess the psychometric properties of the questionnaire and evaluate its suitability as the tool of choice for use in the diagnostic and outcome assessment of tinnitus for clinical and research purposes in the UK. The primary objectives were to (i) determine whether the TFI is reliable, (ii) verify its factor structure, and (iii) evaluate its responsiveness to treatment-related change. These objectives were evaluated in two UK studies. The first was a prospective multi-centre longitudinal validation study in which 255 NHS patients were recruited from audiology clinics to complete the TFI over four different time points in a nine-month period. The second was a retrospective analysis of data collected on the TFI and a battery of other health questionnaires from 294 members of the general public who had previously participated in two-centre randomised controlled trial of a novel tinnitus device. Approaches to psychometric analysis included classical and modern test theories, including Rasch measurement theory. Both approaches led to similar conclusions. Seven of the eight subscales were reliable and valid in both studies, although not as sensitive as the original developers proposed. Classical testing showed the auditory subscale to be reasonably reliable, but Rasch modelling indicated that it did not measure the functional impact of tinnitus. The overall factor structure was not confirmed. The sleep and auditory subscales did not relate to the other subscales and did not fit the model. My recommendation is to calculate the composite TFI score using only six subscales. The sleep subscale should be scored separately and the auditory subscale should not be used.