Being given the diagnosis of a disability generally affects an individual's emotional state, however, this has not previously been investigated with respect to audiology and the diagnosis of hearing loss. The first aim of this study was to describe some of the common initial reactions to the diagnosis of hearing loss (HL). An awareness of these emotional reactions will aid audiologists in counselling their patients. Counselling occurs at the time of the diagnosis and throughout the aural rehabilitation process. However, counselling tuition is currently not provided for audiology students at New Zealand universities and there are few professional development courses for practicing audiologists. The second aim of this study was to evaluate current audiological counselling services and ascertain the impact on patients' decisions to get hearing aids (HAs). To accomplish these aims, 27 adults who had been newly-diagnosed with a HL completed an initial reaction questionnaire, partook in an interview which followed up on the questionnaire, and subsequently completed a second questionnaire at least three weeks later. There were two versions of the second questionnaire, depending on whether they had chosen to have HA(s) fitted. The results found that the common emotions reported were a sense of loss, sadness and resignation, as well as relief. Furthermore, an individual's level of optimism tended to decrease in response to the hearing test result. The ratings of the audiological counselling services were positive and seemed not to significantly influence the individual with respect to their decision to purchase HAs. The two areas of audiological counselling which could be improved related to how the audiologist explained the HL, particularly in relation to the individual's life, and also the provision of information to patients prior to the fitting of the HA. In addition to the data that was collected in relation to these aims, information was collected with respect to patients' perceptions of their HL prior to the hearing test, their interpretation of the hearing test results, and also how the patient's significant other responded to the diagnosis. The information from this study will be useful for equipping audiologists, both new graduates and those with more experience, to provide optimal audiological care for their patients.

Older adults with sensorineural hearing loss have greater difficulty understanding speech than younger adults with equivalent hearing (Gates & Mills, 2005). This increased difficulty may be related to the influence of peripheral, central auditory processing or cognitive deficits and although this has been extensively debated the relative contribution to speech understanding is equivocal (Working Group on Speech Understanding and Aging, 1988). Furthermore, changes to the speech mechanism that occur as a result of age lead to natural degradations of signal quality. Studies involving hearing impaired listeners have not examined the influence of such naturally degraded speech signals. The purpose of this study was to determine: (1) whether older hearing impaired listeners demonstrate differences in speech understanding ability or perceived effort of listening on the basis of the age of the speaker and the predictability of the stimulus, and (2) whether any individual differences in speech understanding were related to central auditory processing ability. The participants included nineteen native speakers of New Zealand English ranging in age from 60 to 87 years (mean = 71.4 years) with age-related sensorineural hearing loss. Each participant underwent a full audiological assessment, three measures of central auditory processing (the Dichotic Digits Test, the Random Gap Detection Test and the Staggered Spondaic Words Test), and completed a computer-based listening experiment containing phrases of high and low predictability spoken by two groups: (1) young adults (18 – 30 years) and (2) older adults (70 years and above). Participants were required to repeat stimulus phrases as heard, with the researcher entering orthographic transcriptions into the custom-designed computer programme. An Analysis of Covariance (ANCOVA) was used to determine if significant differences existed in percentage words correct scores as a factor of speaker group (young versus older speakers) and stimulus predictability (high predictability versus low predictability phrases), with level of presentation (dB) as a covariate. Results demonstrated that although there were no significant differences in percentage words correct with regards to speaker group as expected, lower scores were achieved for low predictability phrases. In addition, increased listener effort was required when listening to the speech from the older adult group and during the low predictability phrase condition. Positive correlations were found between word understanding scores and tests of dichotic separation, which suggests that central auditory processing deficits contribute to the speech understanding difficulties of older adults. The implications of these findings for audiological assessment and rehabilitation are explored.

Hearing loss has a prevalence of 10.3% in New Zealand, with the Māori population being disproportionately affected compared to the non-Māori population. Hearing loss is an impairment that is under-recognised, under-reported and under-treated. This can be explained by the many existing barriers – the shortage of audiological services, financial cost to an individual seeking treatment, the stigma of both hearing loss and hearing aids, and healthcare seeking rates, particularly among the Māori population. This study aimed to develop a Māori language adaptive digit triplet test that could be offered remotely via the telephone and Internet as a hearing-screening test. Three sets of recordings were made of digit triplets spoken in te reo Māori by a female speaker. Two of these sets were selected for normalisation in speech noise. Normal-hearing participants (8 listeners) with hearing thresholds ≤20 dB HL were tested to establish the intelligibility of the individual recorded digits at various signal-to-noise ratios (-13, -10.5, -8 and -5.5 dB). Psychometric functions were fitted to the intelligibility data, and the digits in each position of the triplet that had the steepest slope were selected as the final test stimuli. The level of each selected digit was then adjusted to achieve equal intelligibility as measured at the midpoints of the psychometric functions. These digits were then assembled into eight equivalent lists of similar difficulty, ready for pilot testing. Due to low participant numbers, the pilot testing phase was not completed. Further development of this test continues as the focus of a follow-on study.

Aim : The purpose of this study was to examine the impact of simulated hearing loss on the acoustic contrasts between declarative questions and declarative statements and on the perception of speech intonation. A further purpose of the study was to investigate whether any such effects are universal or language specific. Method: Speakers included four native speakers of English and four native speakers of Mandarin and Taiwanese, with two female and two male adults in each group. Listeners included ten native English and ten native speakers of Mandarin and Taiwanese, with five female and five male adults in each group. All participants were aged between 19 and 55 years old. The speaker groups were asked to read a list of 28 phrases, with each phrase expressed as a declarative statement or a declarative question separately. These phrases were then filtered through six types of simulated hearing loss configurations, including three levels of temporal jittering for simulating a loss in neural synchrony, a high level of temporal jittering in combination with a high-pass or a low-pass filter that simulate falling and rising audiometric hearing loss configurations, and a vocoder processing procedure to simulate cochlear implant processing. A selection of acoustic measures was derived from the sentences and from some embedded vowels, including /i/, /a/, and /u/. The listener groups were asked to listen to the tokens in their native language and indicate if they heard a statement or a question. Results: The maximum fundamental frequency (F0) of the last syllable (MaxF0-last) and the maximum F0 of the remaining sentence segment (MaxF0-rest) were found to be consistently higher in declarative questions than in declarative statements. The percent jitter measure was found to worsen with simulated hearing loss as the level of temporal jittering increased. The vocoder-processed signals showed the highest percent jitter measure and the spread of spectral energy around the dominant pitch. Results from the perceptual data showed that participants in all three groups performed significantly worse with vocoder-processed tokens compared to the original tokens. Tokens with temporal jitter alone did not result in significantly worse perceptual results. Perceptual results from the Taiwanese group were significantly worse than the English group under the two filtered conditions. Mandarin listeners performed significantly worse with the neutral tone on the last syllable, and Taiwanese listeners performed significantly worse with the rising tone on the last syllable. Perception of male intonation was worse than female intonation with temporal jitter and high-pass filtering, and perception of female intonation was worse than male intonation with most temporal jittering conditions, including the temporal jitter and low-pass filtering condition. Conclusion: A rise in pitch for the whole sentence, as well as that in the final syllable, was identified as the main acoustic marker of declarative questions in all of the three languages tested. Perception of intonation was significantly reduced by vocoder processing, but not by temporal jitter alone. Under certain simulated hearing loss conditions, perception of intonation was found to be significantly affected by language, lexical tone, and speaker gender.

Purpose: To investigate the effects of speaker age, speaker gender, semantic context, signal-to-noise ratio (SNR) and a listener’s hearing status on speech recognition and listening effort in older adults. We examined the hypothesis that older adults would recognize less speech and exert greater listening effort when listening to the speech of younger versus older adult speakers. Method: Speech stimuli were recorded from 12 adult speakers classified as “younger” (three males and three females aged 18-31 years) and “older” (three males and three females aged 69-89) respectively. A computer-based subjective rating was conducted to confirm that the speakers were representative of younger and older speakers. Listeners included 20 older adults (aged 65 years and above), who were divided into two age-matched groups with and without hearing loss. All listening and speaking participants in the study were native speakers of New Zealand English. A dual-task paradigm was used to measure speech recognition and listening effort; the primary task involved recognition of target words in sentences containing either high or low contextual cues, while the secondary task required listeners to memorise the target words for later recall, following a set number of sentences. Listening tasks were performed with a variety of listening conditions (quiet, +5 dB SNR and 0dB SNR). Results: There were no overall differences in speech recognition scores or word recall scores for the 20 older listeners, when listening to the speech of the younger versus older speakers. However, differential effects of speaker group were observed in the two semantic context conditions (high versus low context). Older male speakers were the easiest to understand when semantic context was low; however, for sentences with high semantic context, the older male group were the most difficult to understand. Word recall scores were also significantly higher in the most challenging listening condition (low semantic context, 0 dB SNR), when the speaker was an older male. Conclusion: Differential effects of speaker group were observed in the two semantic context conditions (high versus low context) suggesting that different speech cues were used by listeners, as the level of context varied. The findings provide further evidence that, in challenging listening conditions, older listeners are able to use a wide range of cues, such as prosodic features and semantic context to compensate for a degraded signal. The availability of these cues depends on characteristics of the speaker, such as rate of speech and prosody, as well as characteristics of the listener and the listening environment. .

Hearing impairment (HI) is a growing health issue in today’s ageing society. Research has suggested that individuals with HI may experience increased levels of anxiety. Previous research has mainly focused on anxiety as a trait; recent research, however, has looked at state anxiety in the hearing impaired population. Cognitive anxiety is a state anxiety that occurs when people encounter a situation which does not lie within their construct system. As a result, they may experience anxiety as they are unable, or only partially able, to interpret the event meaningfully and are therefore unable to judge the implications of this event. The following study aimed to use the Cognitive Anxiety Scale to investigate relationships between cognitive anxiety and client variables in hearing impaired individuals, adding to the small amount of research currently available in this area. The following research questions were investigated: (1) Is there a relationship between cognitive anxiety level and (a) age, (b) gender, (c) audiometric variables, and (d) quality of life? (2) Is there a significant difference between the level of cognitive anxiety for the participants who purchased and kept hearing aids and those who did not? Twenty-five hearing impaired individuals who were consulting an audiologist for the first time participated in this study, with the cognitive anxiety interview conducted prior to the audiological assessment. The results indicated that cognitive anxiety was significantly related to an ability to understand speech in noise and quality of life, and that hearing aid adopters exhibited greater levels of cognitive anxiety than non-adopters. These results confirm that cognitive anxiety is indeed experienced by adults with HI, and suggest that it may be a factor which motivates people to adopt hearing aids. Further research is needed to confirm and further investigate the relationships with client variables. By listening for signs of cognitive anxiety, an audiologist may be able to gauge if a client is ready for rehabilitation, and encourage the process by exploring the effects of HI on communication situations, employing speech in noise testing, and including the significant other in the process.

The aim of the present thesis was to examine possible cognitive consequences of acquired hearing loss and the possible impact of these cognitive consequences on the ability to process spoken language presented through visual speechreading or through a cochlear implant. The main findings of the present thesis can be summarised in the following conclusions: (a) The phonological processing capabilities of individuals who have acquired a severe hearing loss or deafness deteriorate progressively as a function of number of years with a complete or partial auditory deprivation. (b) The observed phonological deterioration is restricted to certain aspects of the phonological system. Specifically, the phonological representations of words in the mental lexicon are of less good quality, whereas the phonological system in verbal working memory is preserved. (c) The deterioration of the phonological representations has a negative effect on the individual's ability to process speech, either presented visually (i.e., speechreading) or through a cochlear implant, as it may impair word recognition processes which involve activation of and discrimination between the phonological representations in the lexicon. (d) Thus, the present research describes an acquired cognitive disability not previously documented in the literature, and contributes to the context of other populations with phonological disabilities by showing that a complete or partial deprivation of auditory speech stimulation in adulthood can give rise to a phonological disability. (e) From a clinical point of view, the results from the present thesis suggest that early cochlear implantation after the onset of an acquired severe hearing loss is an important objective in order to reach a high level of speech understanding with the implant.

Melanin is the dark pigment found in most organisms that gives color to the skin, hair, feathers, and eyes of vertebrates. While melanin is known to also be present in the stria vascularis of the mammalian cochlea, its function in the inner ear is still unknown. Some previous studies have indicated that melanin may serve to protect the mammalian ear from hearing loss. Minimal previous research on melanin within the inner ears of fishes has been conducted. In this study, the melanin levels in the inner ears of different color morphs of two fish species (Poecilia latipinna and Cyprinus carpio) were examined, as well as the potential protective role of melanin from acoustical stress. To identify the relationship between fish color morph and inner ear melanin, a spectrophotometric melanin assay was used for dissected inner ears, and transmission electron microscopy (TEM) was used to examine melanosome structure in the crus commune of the inner ears. For each color morph and species, hearing thresholds were quantified before and after sound exposure (150 Hz tone at 165 dB re 1 μPa for 48 h) by measuring auditory evoked potentials (AEPs). Melanin levels were associated with scale color, with black morphs having more inner ear melanin than white or golden morphs. TEM imaging showed that melanosome size varied among color morphs, with black P. latipinna morphs having larger melanosomes than white morphs. Hearing thresholds did not differ significantly among color morphs before sound exposure in either species. However, hearing thresholds post-sound exposure and the associated threshold shifts significantly differed between black morphs and other color morphs in the two species, with black morphs having lower thresholds and exhibiting less hearing loss than the other morphs. This suggests that melanin plays a protective role in the teleost inner ear, similar to what other researchers have found in mammalian models. Teleost fishes may be a new, more efficient model for testing melanin's function in the inner ear and how it interacts with stress from acoustical trauma and ototoxic drugs.

Person with hearing impairment (PHI) and their Communication partners (CPs) have a range of experiences and milestones before, during and after their audiological assessment and/or rehabilitation sessions. The term ‘patient journey’ refers to understanding the experiences and the processes the patient goes through during the course of the disease and the treatment regime. The aims of the current thesis were: (1) to further develop patient journey models of individuals with gradual-onset hearing impairment and CPs by taking their views into consideration; (2) to develop the patient journey model for PHI of sudden-onset; (3) to develop a self-reported measure of hearing disability acceptance and to study its construct and concurrent validity; (4) to investigate the health behaviour change characteristics of people noticing hearing difficulties using the stages-of-change model.  Papers I (n=32) and III (n=9) were aimed at further developing the journey model of PHI and their CPs proposed by the Ida Institute. Both studies employed qualitative methods (i.e., focus groups and interviews for data collection and thematic analysis for data analysis), and defined the models based on the perspectives of PHI and CPs both of which had seven main phases. These data were compared with the professionals’ perspectives of the journey as reported in the Ida Institute model which had six main phases. Our studies highlight new phases (i.e., self-evaluation in PHI journey and adaptation in CP journey) and also various commonalities and differences in the perspectives expressed by professionals and patients. Paper II included a pilot study to explore the patient journey of sudden-onset acquired hearing impairment from both professionals (n=16) and patients (n=4) perspectives. Both identified all the six main phases, which include: awareness; movement; diagnostics; rehabilitation; self-evaluation; and resolution. The pre-awareness phase may hinder the realisation of hearing loss in persons with gradual onset hearing loss, whereas it is far more straightforward in persons with sudden-onset due to its nature of onset. Papers IV and V employed a cross-sectional design (n=90). Paper IV was aimed at developing a Hearing Disability Acceptance Questionnaire (HDAQ), and to study its construct and concurrent validity. Results suggested that the HDAQ has a two factor structure which explains 75.7% of the variance and had good internal consistency (Cronbach’s alpha of 0.86). Also, the scale had good concurrent validity in relation to self-reported hearing disability, self-reported anxiety and depression and readiness to change measures. Paper V was aimed at understanding the stages-of-change in adults with hearing disability using the University of Rhode Island Change Assessment Scale.  As predicted a high percentage of participants (over 90%) were in the contemplation and preparation stages, supporting the stages-of-change model. Overall, the papers presented in this thesis may contribute to a better understanding of process of change through hearing impairment in PHI and their CPs. / Personer med hörselnedsättning (eng. PHI) och deras kommunikationspartners (eng. CPs) har en uppsättning upplevelser och erfarenheter före, under och efter audiologisk bedömning och/eller hörselrehabilitering. Begreppet "patientprocess" avser förståelsen av de erfarenheter och de förändringsprocesser patienten genomgår under sjukdomsförloppet och behandlingen av denna. Syftet med avhandlingen var: (1) att ytterligare utveckla individuella modeller för patientprocessen vid gradvis debut av hörselnedsättning och att ta CPs erfarenheter under beaktande, (2) att utveckla modeller för patientprocessen vid plötslig debut av hörselnedsättning, (3) att utveckla självskattningsmått på acceptans av hörselnedsättning och att studera dess begreppsvaliditet och samtidig validitet, (4) att undersöka beteendeförändring avsende hälsa för personer som upplever hörselnedsättning. Artikel I (n = 32) och artikel III (n = 9) syftade bland annat till att vidareutveckla modell av patientprocessen som och deras kommunikationspartner som föreslagits av Ida Institutet. I båda studierna användes kvalitativa metoder (fokusgrupper och intervjuer för datainsamling och tematisk analys) för att bygga modeller av patientprocessen personen med hörselnedsättning och dess kommunikationspartner, där båda modellerna kom att inkludera sju huvudfaser av processen. Resultaten jämfördes med sjukvårdspersonalens perspektiv på patientprocessen enligt Ida Institutets modell. Studierna visar nya faser (självvärdering för PHIs process och anpassning för CPs process). Dessutom identifierades likheter och skillnader i jämförelsen mellan sjukvårdspersonalens och patientens perspektiv. Artikel II innehåller en pilotstudie för att undersöka och skapa modeller för patientprocessen vid plötslig förvärvad hörselnedsättning från både vårdgivarens (n = 16) och patientens (n = 4) perspektiv. Båda grupper identifierade alla sex huvudfaser. Dessa inkluderar: medvetenhet; rörelse; diagnos; rehabilitering; självvärdering; och lösning på problemet. Pre-awareness (för-medvetande) fasen kan eventuellt fördröja/förhindra förståelsen för hörselnedsättningen för personer med gradvis tilltagande hörselnedsättning, emedan förståelsen är mer direkt för personer med plötslig förvärvad hörselnedsättning. Artikel IV och artikel V var bägge baserade på en tvärsnittsstudie (n=90). Artikel IV syftade till att utveckla ett frågeformulär angående acceptans av hörselhandikapp (eng. Hearing Disabiliy Acceptance Questionnaire, HDAQ) och att studera dess begreppsvaliditet och samtidig validitet. Resultaten visar att HDAQ fick en två-faktor struktur som förklarde 75,7 % av variansen och uppvisade god intern konsistens (Cronbach’s alpha 0,86). Dessutom hade skalan god samtidig validitet i förhållande till självrapporterad hörselnedsättning, självrapporterad ångest och depression, samt i förhållande till beredskap för förändring. Artikel V (n = 90) syftade till att undersöka stadier av beteendeförändring för personer med tidig, förmodad hörselnedsättning, via den så kallade stages-of-change modellen. Mätinstrumentet för beteendeförändring var University of Rhode Island Change Assessment Scale. Som förväntat var en hög andel av deltagarna (över 90%) i tidiga stadier (eng. contemplation and preparation), vilket stöder stages-of-change modellen. Sammanfattningsvis, bidrar artiklarna i denna avhandling till en bättre förståelse av förändingsprocesser via hörselnedsättning för personer med hörselnedsättning och deras kommunikationspartners.

Hearing loss from noise exposure is one of the most common occupational injuries, and exposure to vibrations may increase the risk of noise-induced hearing loss. Earlier cross-sectional and longitudinal studies found an increased risk of noise-induced hearing loss among workers with vibration-induced white fingers (VWF) symptoms compared to workers without such symptoms. It has been suggested that vibrations to the hand stimulate the sympathetic nervous system and cause vasoconstriction in both the exposed hand and the ears and that this contributes to noise-induced hearing loss. The overall aim of this thesis was to examine how hand-arm vibrations (HAV) interact with noise in the development of noise-induced hearing loss. The experimental study in this thesis examined the effects of HAV and noise, both separately and combined, on the temporary threshold shift (TTS) in hearing in 22 healthy male and female subjects. The two longitudinal studies in this thesis were based on a cohort of 189 male workers at a heavy engineering workshop. The first cohort study examined the risk of noise-induced hearing loss from long-term exposure to HAV and noise. The second cohort study examined if workers with VWF had an increased risk of noise-induced hearing loss compared to workers without such symptoms. Finally, the questionnaire study in this thesis examined the occurrence of Raynaud’s phenomenon among 133 men and women with noise-induced hearing loss in relation to exposure to vibrations. In the experimental study, no differences in TTS in hearing were observed after combined exposure to HAV and noise compared to exposure to only noise. In the first cohort study, there was an increased risk of noise-induced hearing loss with increased exposure to HAV in a noisy environment. In the second cohort study, it was found that workers with VWF had an increased risk of noise-induced hearing loss compared to workers without VWF. In the questionnaire study, many men and women with noise-induced hearing loss had used hand-held vibrating machines suggesting that vibrations might contribute to noise-induced hearing loss. A high prevalence of Raynaud’s phenomenon was found among men. This thesis demonstrated that there was a long-term effect on noise-induced hearing loss from combined exposure to noise and HAV, but no short-term effect, and that having Raynaud’s phenomenon may also increase the risk of noise-induced hearing loss. / Många arbetare använder sig av handhållna vibrerande verktyg. Det utsätter dem för höga nivåer av både buller och vibrationer. Människor som utsätts för höga bullernivåer under lång tid kan skada sin hörsel. Risken för hörselnedsättning orsakad av buller kan eventuellt öka om personen samtidigt är utsatt för vibrationer från handhållna vibrerande verktyg. Syftet med avhandlingen var att studera om vibrationer i kombination med buller ökar risken för hörselnedsättning. Avhandlingen består av fyra studier. Den första studien är en experimentell studie med 22 friska deltagare med god hörsel. Denna studie undersökte hur hörseln tillfälligt påverkas av buller och vibrationer, separat och i kombination. Den andra och tredje studien bygger på en population bestående av 189 verkstadsarbetare i Sundsvall som följts regelbundet sedan 1987. Den andra studien undersökte om det finns en ökad risk för hörselnedsättning för arbetare som utsätts för buller och vibrationer under lång tid. Den tredje studien undersökte om arbetare med vita fingrar har en ökad risk för hörselnedsättning än arbetare utan vita fingrar. Vita fingrar är en kärlskada orsakad av vibrationer som gör att fingrarna reagerar onormalt snabbt på kyla. Fingrarna blir vita när blodtillförseln till dem stryps. Den fjärde studien är en enkätstudie med 342 kvinnor och män som har en bekräftad hörselnedsättning orsakad av buller. Studien undersökte hur många ur denna grupp som utsätts för vibrationer samt har vita fingrar. Resultaten från studierna visar att det inte finns någon skillnad i hörselpåverkan från buller och vibrationer i kombination jämfört med enbart buller under kort tid. De som utsätts för vibrationer från handhållna vibrerande verktyg i en bullrig miljö under lång tid har en ökad risk för hörselnedsättning. Arbetare med vita fingrar har en högre risk för hörselnedsättning än de utan. En hög andel av de med hörselnedsättning orsakad av buller använder sig av handhållna vibrerande verktyg. I studien fanns även en hög andel med vita fingrar. Sammanfattningsvis visar resultaten att det finns en långtidseffekt av buller och vibrationer på hörselnedsättning men inte någon korttidseffekt, och att vita fingrar kan påverka risken för hörselnedsättning.