Cross-modal functional connectivity supports speech understanding in cochlear implant users.

Sensory deprivation can lead to cross-modal cortical changes, whereby sensory brain regions deprived of input may be recruited to perform atypical function. Enhanced cross-modal responses to visual stimuli observed in auditory cortex of postlingually deaf cochlear implant (CI) users are hypothesized to reflect increased activation of cortical language regions, but it is unclear if this cross-modal activity is "adaptive" or "mal-adaptive" for speech understanding. To determine if increased activation of language regions is correlated with better speech understanding in CI users, we assessed task-related activation and functional connectivity of auditory and visual cortices to auditory and visual speech and non-speech stimuli in CI users (n = 14) and normal-hearing listeners (n = 17) and used functional near-infrared spectroscopy to measure hemodynamic responses. We used visually presented speech and non-speech to investigate neural processes related to linguistic content and observed that CI users show beneficial cross-modal effects. Specifically, an increase in connectivity between the left auditory and visual cortices-presumed primary sites of cortical language processing-was positively correlated with CI users' abilities to understand speech in background noise. Cross-modal activity in auditory cortex of postlingually deaf CI users may reflect adaptive activity of a distributed, multimodal speech network, recruited to enhance speech understanding.

Experienced hearing aid users' perspectives of assessment and communication within audiology: a qualitative study using digital methods.

OBJECTIVE: To explore experienced hearing aid users' perspectives of audiological assessments and the patient-audiologist communication dynamic during clinical interactions. DESIGN: A qualitative study was implemented incorporating both an online focus group and online semi-structured interviews. Sessions were audio-recorded and transcribed verbatim. Iterative-inductive thematic analysis was carried out to identify themes related to assessment and communication within audiology practice. STUDY SAMPLES: Seven experienced hearing aid users took part in an online focus group and 14 participated in online semi-structured interviews (age range: 22 - 86 years; 9 males, 11 females). RESULTS: Themes related to assessment included the unaided and aided testing procedure and relating tests to real world hearing difficulties. Themes related to communication included the importance of deaf aware communication strategies, explanation of test results and patient centred care in audiology. CONCLUSION: To ensure hearing aid services meet the needs of the service users, we should explore user perspectives and proactively adapt service delivery. This approach should be ongoing, in response to advances in hearing aid technology. Within audiology, experienced hearing aid users' value (1) comprehensive, relatable hearing assessment, (2) deaf aware patient-audiologist communication, (3) accessible services and (4) a personalised approach to recommend suitable technology and address patient specific aspects of hearing loss.

A systematic review of the impact of adjusting input dynamic range (IDR), electrical threshold (T) level and rate of stimulation on speech perception ability in cochlear implant users.

OBJECTIVE: To systematically review the evidence of how adjustments of the electrical threshold (T) level, input dynamic range (IDR) and electrical stimulation rate impact on speech perception for cochlear implant (CI) users. DESIGN: Systematic review. STUDY SAMPLE: A search of two electronic data sources yielded 32 studies, which met the inclusion criteria. A quality assessment and two evidence-based practice (EBP) review rating schemes were used to grade studies. RESULTS: Due to the heterogeneity of speech perception measures, CI device type and study design, comparisons were made by structured review. CONCLUSION: The quality of studies was found to be moderate to poor. Increasing T levels above behavioural threshold, or as a proportion of electrical dynamic range (EDR), has been demonstrated to improve perception of monosyllables in quiet and sentences in both quiet and in noise. Specific IIDR and IDR setting may improve perception of monosyllables in quiet and sentences in noise. However, no recommendation could be determined for setting rate of stimulation as speech perception varied significantly across rates examined. To optimise speech perception, a bespoke approach to parameter setting providing an individualised CI fitting is recommended; however, detail of how to optimise settings and the interactions between parameters is as yet unknown.

Comparison of Different Hearing Aid Prescriptions for Children.

OBJECTIVES: To assess whether there are significant differences between speech scores for different hearing aid prescription methods, specifically DSL i/o, DSL V, and NAL-NL1, using age-appropriate closed- and open-set speech tests with young children, designed to avoid floor and ceiling effects. DESIGN: Participants were 44 children with moderate or severe bilateral hearing loss, 8 aged 2 to 3 years, 15 aged 4 to 5 years, and 21 aged 6 to 9 years. Children wore bilateral hearing aids fitted with each prescription method in turn in a balanced double-blind design. The speech tests used with each child (and for some tests the levels) were chosen so as to avoid floor and ceiling effects. For the closed-set tests, the level used was selected for each child based on their hearing loss. The tests used were: (1) The closed-set Consonant Confusion Test of word identification; (2) The closed-set Chear Auditory Perception Test (CAPT) of word identification. This has separate sections assessing discrimination of consonants and vowels and detection of consonants; (3) The open-set Cambridge Auditory Word Lists for testing word identification at levels of 50 and 65 dBA, utilizing 10 consonant-vowel-consonant real words that are likely to be familiar to children aged 3 years or older; (4) The open-set Common Phrases Test to measure the speech reception threshold in quiet; (5) Measurement of the levels required for identification of the Ling 5 sounds, using a recording of the sounds made at the University of Western Ontario. RESULTS: Scores for the Consonant Confusion Test and CAPT consonant discrimination and consonant detection were lower for the NAL-NL1 prescription than for the DSL prescriptions. Scores for the CAPT vowel-in-noise discrimination test were higher for DSL V than for either of the other prescriptions. Scores for the Cambridge Auditory Word Lists did not differ across prescriptions for the level of 65 dBA, but were lower for the NAL-NL1 prescription than for either of the DSL prescriptions for the level of 50 dBA. The speech reception threshold measured using the Common Phrases Test and the levels required for identification of the Ling 5 sounds were higher (worse) for the NAL-NL1 prescription than for the DSL prescriptions. CONCLUSIONS: The higher gains prescribed by the DSL i/o and DSL V prescription methods relative to NAL-NL1 led to significantly better detection and discrimination of low-level speech sounds.

Closed-Set Speech Discrimination Tests for Assessing Young Children.

OBJECTIVE: The main objective of this study is to obtain data assessing normative scores, test-retest reliability, critical differences, and the effect of age for two closed-set consonant-discrimination tests. DESIGN: The two tests are intended for use with children aged 2 to 8 years. The tests were evaluated using normal-hearing children within the appropriate age range. The tests were (1) the closed-set consonant confusion test (CCT) and (2) the consonant-discrimination subtest of the closed-set Chear Auditory Perception Test (CAPT). Both were word-identification tests using stimuli presented at a low fixed level, chosen to avoid ceiling effects while avoiding the use of background noise. Each test was administered twice. RESULTS: All children in the age range 3 years 2 months to 8 years 11 months gave meaningful scores and were able to respond reliably using a computer mouse or a touch screen to select one of four response options displayed on a screen for each trial. Assessment of test-retest reliability showed strong agreement between the two test runs (interclass correlation ≥ 0.8 for both tests). The critical differences were similar to those for other monosyllabic speech tests. Tables of these differences for the CCT and CAPT are provided for clinical use of the measures. Performance tended to improve with increasing age, especially for the CCT. Regression equations relating mean performance to age are given. CONCLUSIONS: The CCT is appropriate for children with developmental age in the range 2 to 4.5 years and the CAPT is appropriate as a follow-on test from the CCT. If a child scores 80% or more on the CCT, they can be further tested using the CAPT, which contains more advanced vocabulary and more difficult contrasts. This allows the assessment of consonant perception ability and of changes over time or after an intervention.

Assessment and Outcome in Non-Traditional Cochlear Implant Candidates.

The objectives of this study were to assess: (i) patient expectations met as a measure of outcome in early-deafened, late-implanted (non-traditional) cochlear implant recipients and (ii) pre-implantation predictive factors for postoperative speech perception. The notes of 13 recipients were retrospectively reviewed. The mean age at onset of profound deafness was 1.5 years (range 0-6). The mean age at implantation was 37 years (range 22-51 years). Patient expectations were assessed pre-operatively and 1 year after implantation. They were met or exceeded in 129/140 (92%) domains overall. A higher Speech Intelligibility Rating and audiovisual City University of New York sentence score before implantation were found to be positive predictive factors for improved speech discrimination after cochlear implantation.

Using personal response systems to assess speech perception within the classroom: an approach to determine the efficacy of sound field amplification in primary school classrooms.

OBJECTIVES: The assessment of the combined effect of classroom acoustics and sound field amplification (SFA) on children's speech perception within the "live" classroom poses a challenge to researchers. The goals of this study were to determine: (1) Whether personal response system (PRS) hand-held voting cards, together with a closed-set speech perception test (Chear Auditory Perception Test [CAPT]), provide an appropriate method for evaluating speech perception in the classroom; (2) Whether SFA provides better access to the teacher's speech than without SFA for children, taking into account vocabulary age, middle ear dysfunction or ear-canal wax, and home language. DESIGN: Forty-four children from two school-year groups, year 2 (aged 6 years 11 months to 7 years 10 months) and year 3 (aged 7 years 11 months to 8 years 10 months) were tested in two classrooms, using a shortened version of the four-alternative consonant discrimination section of the CAPT. All children used a PRS to register their chosen response, which they selected from four options displayed on the interactive whiteboard. The classrooms were located in a 19th-century school in central London, United Kingdom. Each child sat at their usual position in the room while target speech stimuli were presented either in quiet or in noise. The target speech was presented from the front of the classroom at 65 dBA (calibrated at 1 m) and the presented noise level was 46 dBA measured at the center of the classroom. The older children had an additional noise condition with a noise level of 52 dBA. All conditions were presented twice, once with SFA and once without SFA and the order of testing was randomized. White noise from the teacher's right-hand side of the classroom and International Speech Test Signal from the teacher's left-hand side were used, and the noises were matched at the center point of the classroom (10sec averaging [A-weighted]). Each child's expressive vocabulary age and middle ear status were measured individually and each child's home language and any special educational needs were recorded. RESULTS: All children were able to use the PRS handsets, and the CAPT speech perception test was sufficiently sensitive to highlight differences in perception in the different listening conditions. Scores were higher in quiet than in any noise condition. Results showed that group performance was significantly better with SFA than without it. The main demographic predictor of performance was expressive vocabulary age. SFA gave more benefit to the poorer performers in the group. There were no significant effects on performance relating to middle ear status or home language; however, the size of the population was too small to be able to fully explore these aspects in greater detail. CONCLUSION: PRS together with the CAPT provides a sensitive measure for in situ speech perception testing within the classroom. Vocabulary age has a large effect on a child's ability to perceive the speech signal. SFA leads to improved speech perception, when the speech signal has been degraded because of poor acoustics or background noise and has a particularly large effect for children with lower vocabulary ages.

A Multicenter Comparison of 1-yr Functional Outcomes and Programming Differences Between the Advanced Bionics Mid-Scala and SlimJ Electrode Arrays.

OBJECTIVE: To determine if there is a difference in hearing outcomes or stimulation levels between Advanced Bionics straight and precurved arrays. STUDY DESIGN: Retrospective chart review across three implant centers. SETTING: Tertiary centers for cochlear and auditory brainstem implantation. PATIENTS: One hundred fifteen pediatric and 205 adult cochlear implants (CIs) were reviewed. All patients were implanted under the National Institute for Health and Care Excellence 2009 guidelines with a HiRes Ultra SlimJ or Mid-Scala electrode array. MAIN OUTCOME MEASURES: Hearing preservation after implantation, as well as CI-only listening scores for Bamford-Kowal-Bench sentences were compared 1 year after implantation. Stimulation levels for threshold and comfort levels were also compared 1 year after implantation. RESULTS: Hearing preservation was significantly better with the SlimJ compared with the Mid-Scala electrode array. Bamford-Kowal-Bench outcomes were not significantly different between the two arrays in any listening condition. Stimulation levels were not different between arrays but did vary across electrode contacts. At least one electrode was deactivated in 33% of implants but was more common for the SlimJ device. CONCLUSION: Modern straight and precurved arrays from Advanced Bionics did not differ in hearing performance or current requirements. Although hearing preservation was possible with both devices, the SlimJ array would still be the preferred electrode in cases where hearing preservation was a priority. Unfortunately, the SlimJ device was also prone to poor sound perception on basal electrodes. Further investigation is needed to determine if deactivated electrodes are associated with electrode position/migration, and if programming changes are needed to optimize the use of these high-frequency channels.

The effects of age on temporal fine structure sensitivity in monaural and binaural conditions.

OBJECTIVE: To extend the study of Hopkins and Moore (2011) by examining the effect of age in the medium age range on sensitivity to temporal fine structure (TFS), which is assumed to be represented in the patterns of phase locking in the auditory nerve. DESIGN: Monaural TFS sensitivity was assessed using the TFS1 test (Moore & Sek, 2009) at centre frequencies of 850 and 2000 Hz, and binaural TFS sensitivity was assessed using the TFS-LF test (Hopkins & Moore, 2010a) at centre frequencies of 500 and 850 Hz, using a sensation level of 30 dB. STUDY SAMPLE: Thirty-five newly recruited normal-hearing subjects (thresholds better than 20 dB HL from 250 to 6000 Hz) were tested. Their ages ranged from 22 to 61 years. RESULTS: There was a significant correlation between age and TFS sensitivity at all frequencies for both TFS tests. For the single centre frequency (850 Hz) that was used for both tests, scores for the two tests were modestly but significantly correlated. CONCLUSIONS: Sensitivity to TFS decreases with increasing age. The monaural and binaural TFS tests appear to reflect at least somewhat distinct auditory processes.

Factors Affecting the Use of Speech Testing in Adult Audiology.

OBJECTIVE: The aim of this study was to evaluate hearing health care professionals' (HHPs) speech testing practices in routine adult audiology services and better understand the facilitators and barriers to speech testing provision. DESIGN: A cross-sectional questionnaire study was conducted. STUDY SAMPLE: A sample (N = 306) of HHPs from the public (64%) and private (36%) sectors in the United Kingdom completed the survey. RESULTS: In the United Kingdom, speech testing practice varied significantly between health sectors. Speech testing was carried out during the audiology assessment by 73.4% of private sector HHPs and 20.4% of those from the public sector. During the hearing aid intervention stage, speech testing was carried out by 56.5% and 26.5% of HHPs from the private and public sectors, respectively. Recognized benefits of speech testing included (a) providing patients with relatable assessment information, (b) guiding hearing aid fitting, and (c) supporting a diagnostic test battery. A lack of clinical time was a key barrier to uptake. CONCLUSIONS: Use of speech testing varies in adult audiology. Results from this study found that the percentage of U.K. HHPs making use of speech tests was low compared to that of other countries. HHPs recognized different benefits of speech testing in audiology practice, but the barriers limiting uptake were often driven by factors derived from decision makers rather than clinical rationale. Privately funded HHPs used speech tests more frequently than those working in the public sector where time and resources are under greater pressure and governed by guidance that does not include a recommendation for speech testing. Therefore, the inclusion of speech testing in national clinical guidelines could increase the consistency of use and facilitate the comparison of practice trends across centers. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.20044457.

A Hearing Screening Protocol for Stroke Patients: An Exploratory Study.

Background: Auditory impairment post stroke is common and may be due to both peripheral hearing loss and or central auditory processing disorder (CAPD). When auditory impairment remains untreated, it may impact on patient communication and rehabilitation after stroke. Offering a comprehensive audiological assessment to all stroke patients would be both costly and time-consuming. A brief hearing screening is thus required. Objective: The aim of this study was to determine whether a two-tiered hearing screening approach, with use of a handheld hearing screener and two validated hearing questionnaires could be used as a hearing screening for peripheral hearing loss and CAPD in stroke survivors. The sensitivity and specificity of the screening method was analyzed. Methods: This was a prospective study conducted in a tertiary neurology hospital. Forty-two consecutive stroke patients were recruited and tested within 3-12 months post-onset of their stroke. Three screening tools for the identification of hearing impairment were evaluated in this study: A handheld hearing screener for determination of peripheral audiometric hearing loss and two validated questionnaires (The Amsterdam Inventory Auditory for Disability (AIAD) and the Hearing Handicap Inventory for Elderly (HHIE) questionnaires) for determination of peripheral hearing loss and/or CAPD. Results: The hearing screener had a sensitivity of 92. 59% detecting a hearing loss and specificity of 100%. The greatest test accuracy in identifying a central auditory processing type hearing impairment in stroke patients was found when the handheld hearing screener and the AIAD questionnaire were combined. Conclusion: This study is a first step toward addressing the complex auditory needs of stroke survivors in a systematic manner, with the ultimate aim to support their communication needs and long-term recovery and wellbeing. Registration: Project Identification number 11/0469 and REC ref 11/LO/1675.

Hearing Characteristics of Stroke Patients: Prevalence and Characteristics of Hearing Impairment and Auditory Processing Disorders in Stroke Patients.

BACKGROUND: Stroke survivors may suffer from a range of hearing impairments that may restrict their participation in postacute rehabilitation programs. Hearing impairment may have a significant impact on listening, linguistic skills, and overall communication of the affected stroke patient. However, no studies sought to systematically characterize auditory function of stroke patients in detail, to establish the different types of hearing impairments in this cohort of patients. Such information would be clinically useful in understanding and addressing the hearing needs of stroke survivors. PURPOSE: The present study aimed to characterize and classify the hearing impairments, using a detailed audiological assessment test battery, in order to determine the level of clinical need and inform appropriate rehabilitation for this patient population. RESEARCH DESIGN: A case-control study. STUDY SAMPLE: Forty-two recruited stroke patients who were discharged from a stroke unit and 40 control participants matched for age. DATA COLLECTION AND ANALYSIS: All participants underwent pure-tone audiometry and immittance measurements including acoustic reflex threshold, transient-evoked otoacoustic emissions, auditory-evoked brainstem response, and a central auditory processing assessment battery, performed in a single session. Hearing impairments were classified as peripheral hearing loss (cochlear and neural type), central auditory processing disorder (CAPD), and as a combination of CAPD and peripheral hearing loss. RESULTS: Overall mean hearing thresholds were not significantly different between the control and stroke groups. The most common type of hearing impairment in stroke patients was the combination type, "peripheral and CAPD," in the 61- to 80-yr-old subgroup (in 55%), and auditory processing deficits in 18- to 60-yr-olds (in 40%), which were both significantly higher than in controls. CONCLUSIONS: This is the first study to examine hearing function in detail in stroke patients. Given the importance of hearing for the efficiency of communication, it is essential to identify hearing impairments and differentiate peripheral and central deficits to define an appropriate intervention plan.

Preliminary assessment of the feasibility of using AB words to assess candidacy in adults.

BACKGROUND: Adult cochlear implant (CI) candidacy is assessed in part by the use of speech perception measures. In the United Kingdom the current cut-off point to fall within the CI candidacy range is a score of less than 50% on the BKB sentences presented in quiet (presented at 70 dBSPL). GOAL: The specific goal of this article was to review the benefit of adding the AB word test to the assessment test battery for candidacy. RESULTS: The AB word test scores showed good sensitivity and specificity when calculated based on both word and phoneme scores. The word score equivalent for 50% correct on the BKB sentences was 18.5% and it was 34.5% when the phoneme score was calculated; these scores are in line with those used in centres in Wales (15% AB word score). CONCLUSION: The goal of the British Cochlear Implant Group (BCIG) service evaluation was to determine if the pre-implant assessment measures are appropriate and set at the correct level for determining candidacy, the future analyses will determine whether the speech perception cut-off point for candidacy should be adjusted and whether other more challenging measures should be used in the candidacy evaluation.

Simultaneous Assessment of Speech Identification and Spatial Discrimination: A Potential Testing Approach for Bilateral Cochlear Implant Users?

With increasing numbers of children and adults receiving bilateral cochlear implants, there is an urgent need for assessment tools that enable testing of binaural hearing abilities. Current test batteries are either limited in scope or are of an impractical duration for routine testing. Here, we report a behavioral test that enables combined testing of speech identification and spatial discrimination in noise. In this task, multitalker babble was presented from all speakers, and pairs of speech tokens were sequentially presented from two adjacent speakers. Listeners were required to identify both words from a closed set of four possibilities and to determine whether the second token was presented to the left or right of the first. In Experiment 1, normal-hearing adult listeners were tested at 15° intervals throughout the frontal hemifield. Listeners showed highest spatial discrimination performance in and around the frontal midline, with a decline at more eccentric locations. In contrast, speech identification abilities were least accurate near the midline and showed an improvement in performance at more lateral locations. In Experiment 2, normal-hearing listeners were assessed using a restricted range of speaker locations designed to match those found in clinical testing environments. Here, speakers were separated by 15° around the midline and 30° at more lateral locations. This resulted in a similar pattern of behavioral results as in Experiment 1. We conclude, this test offers the potential to assess both spatial discrimination and the ability to use spatial information for unmasking in clinical populations.

Using singing to nurture children's hearing? A pilot study.

This article reports a pilot study of the potential benefits of a sustained programme of singing activities on the musical behaviours and hearing acuity of young children with hearing impairment (HI). Twenty-nine children (n=12 HI and n=17 NH) aged between 5 and 7 years from an inner-city primary school in London participated, following appropriate ethical approval. The predominantly classroom-based programme was designed by colleagues from the UCL Institute of Education and UCL Ear Institute in collaboration with a multi-arts charity Creative Futures and delivered by an experienced early years music specialist weekly across two school terms. There was a particular emphasis on building a repertoire of simple songs with actions and allied vocal exploration. Musical learning was also supported by activities that drew on visual imagery for sound and that included simple notation and physical gesture. An overall impact assessment of the pilot programme embraced pre- and post-intervention measures of pitch discrimination, speech perception in noise and singing competency. Subsequent statistical data analyses suggest that the programme had a positive impact on participant children's singing range, particularly (but not only) for HI children with hearing aids, and also in their singing skills. HI children's pitch perception also improved measurably over time. Findings imply that all children, including those with HI, can benefit from regular and sustained access to age-appropriate musical activities.

Clinical use of electrode differentiation to enhance programming of cochlear implants.

The effect of deactivating indiscriminable cochlear implant (CI) electrodes for unilaterally implanted adults was evaluated using the BKB (Bamford-Kowal-Bench) sentence test in quiet and in pink noise (signal-to-noise ratio of +10dBA) and the adaptive Coordinate Response Measure (CRM). Each CI recipient who failed electrode differentiation (ED) in at least one electrode-pair, based on results of a pure-tone pitch-ranking task received two research programmes to try out in a cross-over study. Research programmes (RP) either employed discriminable electrodes only or the most discriminable two-thirds of the electrodes in the electrode array for CI recipients failing ED for more than a third of the electrodes. The participants were also asked to subjectively report improvement of or decline in sound quality in everyday listening situations. There was significant improvement in CRM speech reception thresholds (SRTs) (Z = -3.24, N = 15, P = 0.001), BKB sentence scores in quiet (t = 3.17, df = 24, P < 0.005) and also in pink noise (t = 2.26, df = 19, P < 0.005) after deactivating indiscriminable electrodes.