Auditory, Visual, and Cognitive Abilities in Normal-Hearing Adults, Hearing Aid Users, and Cochlear Implant Users.

OBJECTIVES: Speech understanding is considered a bimodal and bidirectional process, whereby visual information (i.e., speechreading) and also cognitive functions (i.e., top-down processes) are involved. Therefore, the purpose of the present study is twofold: (1) to investigate the auditory (A), visual (V), and cognitive (C) abilities in normal-hearing individuals, hearing aid (HA) users, and cochlear implant (CI) users, and (2) to determine an auditory, visual, cognitive (AVC)-profile providing a comprehensive overview of a person's speech processing abilities, containing a broader variety of factors involved in speech understanding. DESIGN: Three matched groups of subjects participated in this study: (1) 31 normal-hearing adults (mean age = 58.76), (2) 31 adults with moderate to severe hearing loss using HAs (mean age = 59.31), (3) 31 adults with a severe to profound hearing loss using a CI (mean age = 58.86). The audiological assessments consisted of pure-tone audiometry, speech audiometry in quiet and in noise. For evaluation of the (audio-) visual speech processing abilities, the Test for (Audio) Visual Speech perception was used. The cognitive test battery consisted of the letter-number sequencing task, the letter detection test, and an auditory Stroop test, measuring working memory and processing speed, selective attention, and cognitive flexibility and inhibition, respectively. Differences between the three groups were examined using a one-way analysis of variance or Kruskal-Wallis test, depending on the normality of the variables. Furthermore, a principal component analysis was conducted to determine the AVC-profile. RESULTS: Normal-hearing individuals scored better for both auditory, and cognitive abilities compared to HA users and CI users, listening in a best aided condition. No significant differences were found for speech understanding in a visual condition, despite a larger audiovisual gain for the HA users and CI users. Furthermore, an AVC-profile was composed based on the different auditory, visual, and cognitive assessments. On the basis of that profile, it is possible to determine one comprehensive score for auditory, visual, and cognitive functioning. In the future, these scores could be used in auditory rehabilitation to determine specific strengths and weaknesses per individual patient for the different abilities related to the process of speech understanding in daily life. CONCLUSIONS: It is suggested to evaluate individuals with hearing loss from a broader perspective, considering more than only the typical auditory abilities. Also, cognitive and visual abilities are important to take into account to have a more complete overview of the speech understanding abilities in daily life.

Evaluation of Lifetime Noise Exposure History Reporting.

PURPOSE: The purpose of this study is to critically evaluate lifetime noise exposure history (LNEH) reporting. First, two different approaches to evaluate the cumulative LNEH were compared. Second, individual LNEH was associated with the subjects' hearing status. Third, loudness estimates of exposure activities, by means of Jokitulppo- and Ferguson-based exposure levels, were compared with dosimeter sound-level measurements. METHOD: One hundred one young adults completed the questionnaires, and a subgroup of 30 subjects underwent audiological assessment. Pure-tone audiometry, speech-in-noise intelligibility, distortion product otoacoustic emissions, auditory brainstem responses, and envelope following responses were included. Fifteen out of the 30 subjects took part in a noisy activity while wearing a dosimeter. RESULTS: First, results demonstrate that the structured questionnaire yielded a greater amount of information pertaining to the diverse activities, surpassing the insights obtained from an open-ended questionnaire. Second, no significant correlations between audiological assessment and LNEH were found. Lastly, the results indicate that Ferguson-based exposure levels offer a more precise estimation of the actual exposure levels, in contrast to Jokitulppo-based estimates. CONCLUSIONS: We propose several recommendations for determining the LNEH. First, it is vital to define accurate loudness categories and corresponding allocated levels, with a preference for the loudness levels proposed by Ferguson et al. (2019), as identified in this study. Second, a structured questionnaire regarding LNEH is recommended, discouraging open-ended questioning. Third, it is essential to include a separate category exclusively addressing work-related activities, encompassing various activities for more accurate surveying.

The effect of age on the hearing-related quality of life in normal-hearing adults.

INTRODUCTION: Recently, a new holistic Patient Reported Outcome Measure (PROM) to assess hearing-related quality of life was developed, named the hearing-related quality of life questionnaire for Auditory-VIsual, COgnitive and Psychosocial functioning (hAVICOP). The purpose of the current study was to evaluate if the hAVICOP is sufficiently sensitive to detect an age effect in the hearing-related quality of life. METHODS: One-hundred thirteen normal-hearing participants (mean age: 42.13; range: 19 to 69 years) filled in the entire hAVICOP questionnaire online through the Research Electronic Data Capture surface. The hAVICOP consists of 27 statements, across three major subdomains (auditory-visual, cognitive, and psychosocial functioning), which have to be rated on a visual analogue scale ranging from 0 (rarely to never) to 100 (almost always). Mean scores were calculated for each subdomain separately as well as combined within a total score; the worse one's hearing-related quality of life, the lower the score. Linear regression models were run to predict the hAVICOP total as well as the three subdomain scores from age and sex. RESULTS: A significant main effect of age was observed for the total hAVICOP and all three subdomain scores, indicating a decrease in hearing-related quality of life with increasing age. For none of the analyses, a significant sex effect was found. CONCLUSION: The hAVICOP is sufficiently sensitive to detect an age effect in the hearing-related quality of life within a large group of normal-hearing adults, emphasizing its clinical utility. This age effect on the hearing-related quality of life might be related to the interplay of age-related changes in the bottom-up and top-down processes involved during speech processing.

The P300 Auditory Evoked Potential: A Physiological Measure of the Engagement of Cognitive Systems Contributing to Listening Effort?

OBJECTIVES: This study aimed to explore the potential of the P300 (P3b) as a physiological measure of the engagement of cognitive systems contributing to listening effort. DESIGN: Nineteen right-handed young adults (mean age: 24.79 years) and 20 right-handed older adults (mean age: 58.90 years) with age-appropriate hearing were included. The P300 was recorded at Fz, Cz, and Pz using a two-stimulus oddball paradigm with the Flemish monosyllabic numbers "one" and "three" as standard and deviant stimuli, respectively. This oddball paradigm was conducted in three listening conditions, varying in listening demand: one quiet and two noisy listening conditions (+4 and -2 dB signal to noise ratio [SNR]). At each listening condition, physiological, behavioral, and subjective tests of listening effort were administered. P300 amplitude and latency served as a potential physiological measure of the engagement of cognitive systems contributing to listening effort. In addition, the mean reaction time to respond to the deviant stimuli was used as a behavioral listening effort measurement. Last, subjective listening effort was administered through a visual analog scale. To assess the effects of listening condition and age group on each of these measures, linear mixed models were conducted. Correlation coefficients were calculated to determine the relationship between the physiological, behavioral, and subjective measures. RESULTS: P300 amplitude and latency, mean reaction time, and subjective scores significantly increased as the listening condition became more taxing. Moreover, a significant group effect was found for all physiological, behavioral, and subjective measures, favoring young adults. Last, no clear relationships between the physiological, behavioral, and subjective measures were found. CONCLUSIONS: The P300 was considered a physiological measure of the engagement of cognitive systems contributing to listening effort. Because advancing age is associated with hearing loss and cognitive decline, more research is needed on the effects of all these variables on the P300 to further explore its usefulness as a listening effort measurement for research and clinical purposes.

Development of the hearing-related quality of life questionnaire for auditory-visual, cognitive and psychosocial functioning (hAVICOP).

INTRODUCTION: There is a need for a validated and standardized self-assessment instrument to assess the subjective effect of hearing aid (HA) use and/or cochlear implantation (CI) on different aspects of functioning in daily life. The aim of this study was to develop a new holistic Patient Reported Outcome Measure (PROM) to assess hearing-related quality of life. The new PROM is titled the hearing-related quality of life questionnaire for Auditory-VIsual, COgnitive and Psychosocial functioning (hAVICOP). METHODS: A conceptual framework was set up and test items were prepared per domain. Preliminary testing involved a semi-structured interview-based assessment in normal-hearing and hearing-impaired adults and an expert panel. For the further psychometric evaluation, a new sample of 15 adult HA users, 20 adult CI users and 20 normal-hearing adults filled in the refined version of the hAVICOP, the Speech, Spatial and Qualities of Hearing Scale, the Nijmegen Cochlear Implant Questionnaire and the TNO-AZL Questionnaire for Adult's Health-Related Quality of Life. Based on these results, a factor analysis was conducted and internal consistency, discriminant validity and concurrent construct validity were determined. RESULTS: The final version of the hAVICOP consists of three domains for hearing-related quality of life: (1) auditory-visual functioning, (2) cognitive functioning, and (3) psychosocial functioning. A sufficient internal consistency was found, and discriminant validity and concurrent construct validity were good. CONCLUSIONS: A new PROM to assess hearing-related quality of life was developed, named the hAVICOP. In the future the validity and reliability should be examined further.

Evolution of hearing in young adults: Effects of leisure noise exposure, attitudes, and beliefs toward noise, hearing loss, and hearing protection devices.

Context: Young people expose themselves to high levels of noise during various leisure activities and might thus be at risk of acquiring hearing-related problems due to leisure noise exposure. Aim: The aim of this study was to compare the hearing status, amount of leisure noise exposure, and attitudes and beliefs toward noise, hearing loss, and hearing protection devices (HPDs) in university students at the moment of their enrollment in higher education and after approximately 3 years. Settings and Design: Thirty-four female university students were tested at the moment of their enrollment in higher education and after approximately 3 years. Method and Material: Hearing was evaluated using pure-tone audiometry and transient evoked and distortion product otoacoustic emissions. A questionnaire was used to evaluate leisure noise exposure and attitudes and beliefs toward noise, hearing loss, and HPDs. Results: There were significant differences after the 3-year period: a deterioration in hearing at some tested frequencies, an increase in the occurrence of temporary tinnitus after leisure noise exposure, an increase in noise exposure related to visiting nightclubs and music venues, and differences in attitudes and beliefs toward noise, hearing loss and HPDs. Conclusions: More longitudinal studies are needed to evaluate the onset and progression of hearing loss due to leisure noise exposure. In the meantime, hearing conservation programs targeting young people should be optimized.

The Views and Experience of Audiologists Working in Flemish Hearing Aid Centers Concerning Cognition Within Audiological Practice.

PURPOSE: This study aimed to get insight into the views and experience of audiologists, employed in Flemish hearing aid centers, concerning cognition within audiological practice. METHOD: An online 49-item questionnaire was developed and subdivided into five categories: (a) work setting, (b) practical experience regarding hearing aid fitting linked to cognition, (c) knowledge regarding the auditory-cognitive perspective of speech understanding, (d) willingness and guidelines to implement cognitive measures within audiological practice, and (e) demographics. Respondents were surveyed during January and February 2021. RESULTS: One hundred twenty-nine audiologists working in Flemish hearing aid centers responded to the entire questionnaire and showed a mean work experience of 8.0 years. Results revealed that cognition was taken into account, especially within the anamnesis interview and general communication strategy, whereas only a minority took cognition into account when actually fitting hearing aids. Knowledge and experience did not determine whether or not respondents took cognition into account. A willingness to implement cognitive measures in a time-efficient manner in audiological practice was observed among respondents. CONCLUSION: Evidence-based guidelines regarding hearing aid fitting based on an individual's auditory-cognitive profile are needed to improve the quality of hearing rehabilitation. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.19593388.

Investigation of the Relation Between Tinnitus, Cognition, and the Amount of Listening Effort.

PURPOSE: This study aimed to investigate the effect of chronic tinnitus on measures of listening effort and cognitive performance, as well as the relation between cognitive performance and the amount of listening effort obtained by those measures. METHOD: Thirteen normal-hearing young adults with chronic tinnitus were matched with a control group. First, behavioral listening effort was measured using a dual-task paradigm in various favorable and unfavorable listening conditions. Furthermore, verbal working memory, processing speed, selective attention, and cognitive flexibility and inhibition were evaluated. RESULTS: A significant and nonsignificant trend toward more listening effort in the tinnitus group was, respectively, found for the quiet listening condition and the condition with a signal-to-noise ratio of +2 dB. No significant differences in cognitive performances were found between the groups, nor were there significant relationships between the cognitive factors and listening effort scores for either the control or tinnitus group. CONCLUSIONS: Listening effort was increased in the tinnitus group. Although no clear differences in cognitive performance could be found between the tinnitus group and their controls, a trend could be seen whereby selective attention deficits in the subjects with tinnitus may be an important factor that affects the amount of listening effort.

Listening Effort Measured Using a Dual-task Paradigm in Adults With Different Amounts of Noise Exposure.

OBJECTIVES: Excessive noise levels can result in hearing damage and/or hearing-related symptoms, thereby leading to impaired communication and, eventually a decrease in the quality of life. Moreover, in daily practice, subjects often indicate that listening in noisy situations is a challenging and often exhausting experience, even in the absence of a clinically significant hearing loss. Hence, a person's perceived difficulty of the listening situation will also be important to consider. It has been suggested that beyond the peripheral factors, there are some central cognitive correlates of speech understanding that are essential for communication abilities. The aim of the present study was to evaluate the effect of the amount of noise exposure on hearing as measured by pure-tone audiometry and otoacoustic emissions (OAEs) on the one hand and listening effort measured using a dual-task paradigm on the other hand. DESIGN: The study included 152 adults between 18 and 40 years of age. First, participants completed a self-administered questionnaire regarding the amount of noise exposure. Second, hearing status was evaluated using pure-tone audiometry and transient evoked OAEs (TEOAEs) as well as distortion product OAEs (DPOAEs). Finally, listening effort was evaluated using a dual-task paradigm, which consisted of a primary speech-recognition task in different listening conditions and a secondary visual memory task that were performed both separately and simultaneously. Based on the quartiles of their subjective estimation of noise exposure, the participants were categorized into a group with low noise exposure (lower quartile), moderate noise exposure (two middle quartiles), and high noise exposure (upper quartile). RESULTS: There was no significant difference in hearing thresholds between the participants with low, moderate, and high noise exposure for each frequency of the pure-tone audiometry. In contrast, more absent TEOAEs and DPOAEs were found in the high noise exposed group. Regarding the primary speech-recognition task of the dual-task paradigm, no significant difference in speech recognition was found between the different groups of noise exposure. For the amount of listening effort, it was found that across all listening conditions subjects with high noise exposure expend significantly more listening effort compared with subjects with low and moderate noise exposure. CONCLUSIONS: This study is a first exploration of the effects of different amounts of noise exposure on listening effort showing that, listening effort is increased in subjects with high noise exposure compared with subjects with low and medium noise exposure. The most plausible hypothesis pertains to an effect of noise exposure on the peripheral and central auditory system, or a combination of effects on both the auditory system and the high-level cognitive functions necessary for speech understanding in the subjects with high levels of noise exposure. As such, a test for listening effort would be useful as part of a comprehensive test battery within the assessment of subjects exposed to noise.

The Effects of Age, Gender and Test Stimuli on Visual Speech Perception: A Preliminary Study.

INTRODUCTION: To the best of our knowledge, there is a lack of reliable, validated, and standardized (Dutch) measuring instruments to document visual speech perception in a structured way. This study aimed to: (1) evaluate the effects of age, gender, and the used word list on visual speech perception examined by a first version of the Dutch Test for (Audio-)Visual Speech Perception on word level (TAUVIS-words) and (2) assess the internal reliability of the TAUVIS-words. METHODS: Thirty-nine normal-hearing adults divided into the following 3 age categories were included: (1) younger adults, age 18-39 years; (2) middle-aged adults, age 40-59 years; and (3) older adults, age >60 years. The TAUVIS-words consist of 4 word lists, i.e., 2 monosyllabic word lists (MS 1 and MS 2) and 2 polysyllabic word lists (PS 1 and PS 2). A first exploration of the effects of age, gender, and test stimuli (i.e., the used word list) on visual speech perception was conducted using the TAUVIS-words. A mixed-design analysis of variance (ANOVA) was conducted to analyze the results statistically. Lastly, the internal reliability of the TAUVIS-words was assessed by calculating the Chronbach α. RESULTS: The results revealed a significant effect of the used list. More specifically, the score for MS 1 was significantly better compared to that for PS 2, and the score for PS 1 was significantly better compared to that for PS 2. Furthermore, a significant main effect of gender was found. Women scored significantly better compared to men. The effect of age was not significant. The TAUVIS-word lists were found to have good internal reliability. CONCLUSION: This study was a first exploration of the effects of age, gender, and test stimuli on visual speech perception using the TAUVIS-words. Further research is necessary to optimize and validate the TAUVIS-words, making use of a larger study sample.

Visual and Verbal Working Memory and Processing Speed Across the Adult Lifespan: The Effect of Age, Sex, Educational Level, Awakeness, and Hearing Sensitivity.

Objective: To strengthen future methodological choices regarding the measurement of cognition within the field of audiology, the current study aimed to examine the effect of, among other things, hearing sensitivity on the backward corsi tapping task (i.e., visual working memory and processing speed) and the letter-number sequencing task (i.e., verbal working memory and processing speed). Design and Study Sample: The backward corsi tapping task and the letter-number sequencing task were administered to 184 participants, aged between 18 and 69 years. The effect of age, sex, educational level, awakeness, and hearing sensitivity on verbal and visual working memory and processing speed was assessed using stepwise multiple regression analyses. Results: For all outcome variables, a decrease in performance was observed with increasing age. For visual and verbal working memory, males outperformed females, whereas no clear sex effect was observed for visual and verbal processing speed. Hearing sensitivity had only a significant impact on visual processing speed. Conclusion: The importance to evaluate cognitive construct validity within audiological research was highlighted. Further research should focus on investigating the associations between speech understanding on the one hand and the backward corsi tapping task and letter-number sequencing task on the other hand.

Leisure Noise Exposure and Associated Health-Risk Behavior in Adolescents: An Explanatory Study among Two Different Educational Programs in Flanders.

Adolescents frequently engage in noisy leisure activities which can result in hearing-related problems. However, the effect of leisure noise exposure is liable to an individual's risk-taking behavior. Identifying leisure noise activities and relevant factors related to risk-taking behavior in adolescents, are important to optimize hearing conservation programs targeting youngsters. The purpose of the study was to explore the presence of hearing-related symptoms, as well as noise exposure during various activities, and the use of hearing protector devices (HPDs) in adolescents in two educational programs in Flanders. In addition, their attitudes and beliefs towards noise, hearing loss, and HPDs were investigated. The final sample consisted of 247 adolescents. The most important hearing-related symptoms after noise exposure were tinnitus and noise sensitivity. With regard to leisure noise exposure, listening to PMPs was most frequently reported. The use of HPDs during most noisy activities was limited, in accordance with the presence of hearing-related symptoms, considering noise as unproblematic, and having worse scores on subscales of the beliefs about hearing protection and hearing loss scale. In the future, hearing conservation programs should target adolescents specifically for a more health-orientated behavior towards noise exposure, hearing loss, and HPDs.

Short-Term Test-Retest Reliability of Contralateral Suppression of Click-Evoked Otoacoustic Emissions in Normal-Hearing Subjects.

Purpose The objective of the current study was to investigate the short-term test-retest reliability of contralateral suppression (CS) of click-evoked otoacoustic emissions (CEOAEs) using commercially available otoacoustic emission equipment. Method Twenty-three young normal-hearing subjects were tested. An otoscopic evaluation, admittance measures, pure-tone audiometry, measurements of CEOAEs without and with contralateral acoustic stimulation (CAS) to determine CS were performed at baseline (n = 23), an immediate retest without and with refitting of the probe (only CS of CEOAEs; n = 11), and a retest after 1 week (n = 23) were performed. Test-retest reliability parameters were determined on CEOAE response amplitudes without and with CAS, and on raw and normalized CS indices between baseline and the other test moments. Results Repeated-measures analysis of variance indicated no random or systematic changes in CEOAE response amplitudes without and with CAS, and in raw and normalized CS indices between the test moments. Moderate-to-high intraclass correlation coefficients with mostly high significant between-subjects variability between baseline and each consecutive test moment were found for CEOAE response amplitude without and with CAS, and for the raw and normalized CS indices. Other reliability parameters deteriorated between CEOAE response amplitudes with CAS as compared to without CAS, between baseline and retest with probe refitting, and after 1 week, as well as for frequency-specific raw and normalized CS indices as compared to global CS indices. Conclusions There was considerable variability in raw and normalized CS indices as measured using CEOAEs with CAS using commercially available otoacoustic emission equipment. More research is needed to optimize the measurement of CS of CEOAEs and to reduce influencing factors, as well as to make generalization of test-retest reliability data possible.

Central auditory processing and listening effort in normal-hearing children: a pilot study.

OBJECTIVES: The current study aims to assess the link between central auditory processes and listening effort in a group of normal-hearing children. This will provide information over and beyond the standard central auditory processes and might have practical implications for listening situations which often require speech understanding in noisy environments. METHOD: The current study included 35 normal-hearing children from six to eleven years old. Tympanometry, tonal audiometry, and speech audiometry was performed. Different auditory processing skills were assessed using the Frequency Pattern Test, the Staggered Spondaic Word Test, and the Dichotic Digits Test. Finally, a dual-task paradigm was used to evaluate listening effort. This paradigm consisted of the simultaneous performance of a speech-recognition task in different conditions of background noise and a visuospatial memory task using a digital Corsi Block test. RESULTS: Significant correlations between listening effort and several components of the auditory processing tests were established. Specifically, listening effort correlated significantly with some components of the SSWT as well as the DDT. Additionally, the listening effort test showed a significant age effect for the listening condition with the highest Signal-To-Noise Ratio. CONCLUSIONS: Based on the current results, inclusion of listening effort in the test battery for auditory processing disorders would be valuable.

The Effect of Cognition on the Aided Benefit in Terms of Speech Understanding and Listening Effort Obtained With Digital Hearing Aids: A Systematic Review.

Purpose Hearing aids are the primary rehabilitation devices used to compensate for presbycusis, though large intersubject variability in hearing aid benefit has been reported. This systematic review aimed to investigate how intersubject differences in cognition could influence the aided benefit for speech understanding and listening effort with bilateral digital hearing aids. Method Articles were selected through systematic searches in MEDLINE, Embase, Central, and reference lists. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Results The initial search resulted in 1,092 unique hits, of which 16 were included. The effect of cognition on the aided benefit in terms of speech understanding and listening effort was examined in 12 and four studies, respectively. The aided speech and listening effort benefit obtained from hearing aid use in general or from a specific digital feature (i.e., microphone directionality, noise reduction, amplitude compression, and frequency compression) was associated with four cognitive functions (i.e., working memory, processing speed, selective attention, and executive functions). Conclusions Hearing aid users with poorer cognitive functioning derived more aided benefit in terms of speech understanding from hearing aid settings facilitating the matching process between the incoming auditory signal and representations stored in long-term memory. However, since the number of included studies was limited, this trend should be interpreted with caution. Supplemental Material https://doi.org/10.23641/asha.13626509.

2BALANCE: a cognitive-motor dual-task protocol for individuals with vestibular dysfunction.

INTRODUCTION: Aside from primary vestibular symptoms such as vertigo and dizziness, persons with vestibular dysfunction frequently express cognitive and motor problems. These symptoms have mainly been assessed in single-task setting, which might not represent activities of daily living accurately. Therefore, a dual-task protocol, consisting of the simultaneous performance of cognitive and motor tasks, was developed. This protocol assesses cognitive and motor performance in general, as well as cognitive-motor interference in specific. METHODS AND ANALYSIS: The motor component of the 2BALANCE protocol consists of a static and dynamic postural task. These motor tasks are combined with different cognitive tasks assessing visuospatial cognition, processing speed, working memory and response inhibition. First, test-retest reliability will be assessed with an interval of 2 weeks in a group of young adults. Second, the 2BALANCE protocol will be validated in persons with bilateral vestibulopathy. Finally, the protocol will be implemented in persons with unilateral vestibular loss. DISCUSSION AND CONCLUSIONS: The 2BALANCE project aims to elucidate the impact of vestibular dysfunction on cognitive and motor performance in dual-task setting. This protocol represents everyday situations better than single-task protocols, as dual-tasks such as reading street signs while walking are often encountered during daily activities. Ultimately, this project could enable individualised and holistic clinical care in these patients, taking into account single as well as dual-task performance. ETHICS AND DISSEMINATION: The current study was approved by the ethics committee of Ghent University Hospital on 5 July 2019 with registration number B670201940465. All research findings will be disseminated in peer-reviewed journals and presented at vestibular as well as multidisciplinary international conferences and meetings. TRIALS REGISTRATION NUMBER: NCT04126798, pre-results phase.

Psychometric Properties of Cognitive-Motor Dual-Task Studies With the Aim of Developing a Test Protocol for Persons With Vestibular Disorders: A Systematic Review.

OBJECTIVES: Patients suffering from vestibular disorders (VD) often present with impairments in cognitive domains such as visuospatial ability, memory, executive function, attention, and processing speed. These symptoms can be attributed to extensive vestibular projections throughout the cerebral cortex and subcortex on the one hand, and to increased cognitive-motor interference (CMI) on the other hand. CMI can be assessed by performing cognitive-motor dual-tasks (DTs). The existing literature on this topic is scarce and varies greatly when it comes to test protocol, type and degree of vestibular impairment, and outcome. To develop a reliable and sensitive test protocol for VD patients, an overview of the existing reliability and validity studies on DT paradigms will be given in a variety of populations, such as dementia, multiple sclerosis, Parkinson's disease, stroke, and elderly. DESIGN: The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An extensive literature search on psychometric properties of cognitive-motor DTs was run on MEDLINE, Embase, and Cochrane Databases. The studies were assessed for eligibility by two independent researchers, and their methodological quality was subsequently evaluated using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN). RESULTS AND CONCLUSIONS: Thirty-three studies were included in the current review. Based on the reliability and validity calculations, including a static as well as dynamic motor task seems valuable in a DT protocol for VD patients. To evoke CMI maximally in this population, both motor tasks should be performed while challenging the vestibular cognitive domains. Out of the large amount of cognitive tasks employed in DT studies, a clear selection for each of these domains, except for visuospatial abilities, could be made based on this review. The use of the suggested DTs will give a more accurate and daily life representation of cognitive and motor deficiencies and their interaction in the VD population.

The Ototoxic Potential of Cobalt From Metal-on-Metal Hip Implants: Objective Auditory and Vestibular Outcome.

OBJECTIVES: During the past decade, the initial popularity of metal-on-metal (MoM) hip implants has shown a progressive decline due to increasingly reported implant failure and revision surgeries. Local as well as systemic toxic side effects have been associated with excessive metal ion release from implants, in which cobalt (Co) plays an important role. The rare condition of systemic cobaltism seems to manifest as a clinical syndrome with cardiac, endocrine, and neurological symptoms, including hearing loss, tinnitus, and imbalance. In most cases described in the literature, revision surgery and the subsequent drop in blood Co level led to (partial) alleviation of the symptoms, suggesting a causal relationship with Co exposure. Moreover, the ototoxic potential of Co has recently been demonstrated in animal experiments. Since its ototoxic potential in humans is merely based on anecdotal case reports, the current study aimed to prospectively and objectively examine the auditory and vestibular function in patients implanted with a MoM hip prosthesis. DESIGN: Twenty patients (15 males and 5 females, aged between 33 and 65 years) implanted with a primary MoM hip prosthesis were matched for age, gender, and noise exposure to 20 non-implanted control subjects. Each participant was subjected to an extensive auditory (conventional and high-frequency pure tone audiometry, transient evoked and distortion product otoacoustic emissions [TEOAEs and DPOAEs], auditory brainstem responses [ABR]) and vestibular test battery (cervical and ocular vestibular evoked myogenic potentials [cVEMPs and oVEMPs], rotatory test, caloric test, video head impulse test [vHIT]), supplemented with a blood sample collection to determine the plasma Co concentration. RESULTS: The median [interquartile range] plasma Co concentration was 1.40 [0.70, 6.30] µg/L in the MoM patient group and 0.19 [0.09, 0.34] µg/L in the control group. Within the auditory test battery, a clear trend was observed toward higher audiometric thresholds (11.2 to 16 kHz), lower DPOAE (between 4 and 8 kHz), and total TEOAE (1 to 4 kHz) amplitudes, and a higher interaural latency difference for wave V of the ABR in the patient versus control group (0.01 ≤ p < 0.05). Within the vestibular test battery, considerably longer cVEMP P1 latencies, higher oVEMP amplitudes (0.01 ≤ p < 0.05), and lower asymmetry ratio of the vHIT gain (p < 0.01) were found in the MoM patients. In the patient group, no suggestive association was observed between the plasma Co level and the auditory or vestibular outcome parameters. CONCLUSIONS: The auditory results seem to reflect signs of Co-induced damage to the hearing function in the high frequencies. This corresponds to previous findings on drug-induced ototoxicity and the recent animal experiments with Co, which identified the basal cochlear outer hair cells as primary targets and indicated that the cellular mechanisms underlying the toxicity might be similar. The vestibular outcomes of the current study are inconclusive and require further elaboration, especially with respect to animal studies. The lack of a clear dose-response relationship may question the clinical relevance of our results, but recent findings in MoM hip implant patients have confirmed that this relationship can be complicated by many patient-specific factors.

Analysis of probe fitting stimulus properties on transient evoked otoacoustic emissions.

Objective: The objectives of the current study are first, to evaluate the subjective evaluation of probe fitting stimulus properties, and second, to analyse the effects of different probe fittings on transient evoked otoacoustic emission (TEOAE) response and noise amplitudes in subjects.Design: The Q methodology was used to sort 48 probe fittings differing in stimulus properties in seven categories from totally unacceptable to certainly acceptable. Further, TEOAE response and noise amplitudes were measured in one baseline condition with optimal probe fitting and eight experimental conditions with less than optimal probe fittings.Study sample: The probe fittings were ranked by 18 participants, while the repeated measures design was performed in 34 ear.Results: First, it was found that only 19.61% of all distributions of the probe fittings by the participants had a mutual correlation of at least 70.00%. Almost 60% of the variance of distributions was explained by 83.33% of the participants, although most probe fittings significantly differed from other fittings based on spectral broadness. Second, significant differences in TEOAE response and especially noise amplitudes between conditions were found. Further, TEOAE response and noise amplitudes between the baseline and experimental conditions were significantly different depending on ringing and spectral flatness of the stimulus.Conclusion: A substantial amount of subjectivity during TEOAE measurements is involved with regard to the evaluation of probe fitting stimulus properties. TEOAE response but especially noise amplitudes are influenced by varying stimulus parameters which stresses the importance of inspecting these parameters prior to or during EOAE measurements. Although more research is needed, some guidelines regarding these parameters are given which could improve the accuracy of TEOAEs in practice.

Test-Retest Reproducibility of Response Duration in Tinnitus Patients With Positive Residual Inhibition.

Purpose Functional imaging is often used to try to elucidate the pathophysiological mechanism of tinnitus. Residual inhibition, the temporary suppression of tinnitus after application of a masking noise, could be an interesting technique to modulate tinnitus perception in functional imaging paradigms. The purposes of this study were to primarily assess reproducibility of the (partial) positive residual inhibition response duration in patients with tinnitus and to explore its utility in experimental designs. Method Patients with tinnitus exhibiting a (partial) positive residual inhibition response or tinnitus reduction after a 1-min white noise presentation were selected from a broad consulting tinnitus population. In 27 patients, this response was tested 4 times: twice during initial testing and twice during a retest of the psychoacoustic tinnitus measures, 4-8 weeks after initial consultation. In 17 patients with stable residual inhibition responses, reproducibility of response duration, the duration of tinnitus reduction up to pretesting state, was analyzed. Results Initial testing showed a residual inhibition duration of 29.5 s on average. Test-retest reproducibility of response duration was shown to be reliable with an ICC(3, 4) of .871 (95% CI [0.733, 0.948]) and a standard error of measurement of 6.64 s. Conclusions This study indicates the good test-retest reproducibility of residual inhibition duration in our subset of 17 patients with stable (partial) positive residual inhibition. Residual inhibition is, therefore, a technique that can potentially be used for temporary tinnitus manipulation in experimental paradigms to unravel tinnitus pathophysiology.