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Objective: This study evaluated the outcomes of the Oticon Medical Neuro Zti cochlear implant and the Neuro 2 sound processor.Design: Neuro One users were upgraded to Neuro 2. Monosyllabic word identification was evaluated in adults with Neuro One after ≥5 months, with Neuro 2 at upgrade, and with Neuro 2 after 3 months. Self-reported listening ability, satisfaction, and usability were measured in adults and children.Study sample: Participants were 44 adults and 26 children.Results: Speech identification scores in quiet and noise were 58% and 45% with Neuro One and 67% and 55% with Neuro 2 after 3 months, respectively. Hearing impairment duration and number of active electrodes significantly predicted speech identification in noise with Neuro 2. Significantly higher questionnaire ratings were obtained for Neuro 2 than Neuro One regarding listening ability in complex listening situations, comfort and music, as well as nine aspects of satisfaction and usability.Conclusion: This study demonstrates the clinical superiority of the Neuro 2 sound processor over Neuro One in terms of speech identification in quiet and in noise and reported patient benefit and satisfaction. Given the study design, sources of improvement may include factors unrelated to the sound processor itself.
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Implantación Coclear/instrumentación , Implantes Cocleares , Pérdida Auditiva/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Francia , Pérdida Auditiva/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Ruido , Satisfacción del Paciente , Percepción del Habla , Prueba del Umbral de Recepción del Habla , Resultado del Tratamiento , Adulto JovenRESUMEN
Technological advances in the domain of digital signal processing adapted to cochlear implants (CI) are partially responsible for the ever-improving outcomes observed with this neural prosthesis. The goal of the present study was to evaluate audiometric outcomes with a new signal processing strategy implemented in Oticon Medical-Neurelec cochlear implant systems, the xDP strategy. The core of this approach is a preset-based back-end output compression system, modulating a multi-channel transfer function depending on the intensity and information content of input sounds. Twenty adult CI patients, matched for age and CI experience, were included in this study. Pure-tone thresholds and vocal audiometry scores were measured with their former signal processing strategy and with xDP. Speech perception was assessed using dissyllabic words presented in quiet, at different intensity levels: 40, 55, 70, and 85 dB SPL, and in a cocktail party noise at a signal-to-noise ratio of +10 dB. Results with the xDP strategy showed, as awaited, no major modification of pure-tone thresholds. A global increase of speech perception scores was observed after a 1-month habituation period, with significant improvements for speech perception in quiet for moderate (55 dB SPL), loud speech sounds (85 dB SPL), and speech-in-noise comprehension. Subjective signal quality assessment showed a preference for Crystalis(xDP) over the former strategy. These results allow the quantification of improvements provided by the xDP signal processing strategy.
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Audiometría/métodos , Implantación Coclear , Diseño Asistido por Computadora , Trastornos de la Audición , Percepción del Habla , Adulto , Anciano , Implantación Coclear/efectos adversos , Implantación Coclear/métodos , Implantes Cocleares , Femenino , Trastornos de la Audición/diagnóstico , Trastornos de la Audición/fisiopatología , Trastornos de la Audición/cirugía , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Fonética , Procesamiento de Señales Asistido por Computador , Relación Señal-RuidoRESUMEN
OBJECTIVE: The aim of this study was to evaluate the potential improvements of speech perception and sound quality provided by a multiband single channel noise-reduction algorithm based on the modified Wiener-filter adapted to cochlear implant sound processing. DESIGN: This study was a longitudinal trial with a repeated-measures design. Outcome measures were performed on the first day when the noise reduction feature was provided and after a one month habituation period. Objective measures included pure-tone thresholds and vocal audiometry assessments. Speech perception was measured in quiet and in the presence of two types of noise: a stationary speech shaped noise and a two-talker cocktail noise. Subjective sound quality was assessed using a ten item questionnaire. STUDY SAMPLE: Thirteen post-lingual deaf adults, experienced users of a cochlear implant system, took part in this study. RESULTS: The noise-reduction algorithm provided a benefit for the perception of speech presented in a stationary speech shaped noise and an overall improvement in subjective sound quality ratings. CONCLUSIONS: It was shown that a single channel noise reduction system based on a modified Wiener-filter approach can improve speech in noise perception performance and subjective sound quality in cochlear implant patients.
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Algoritmos , Implantes Cocleares , Ruido , Procesamiento de Señales Asistido por Computador , Adulto , Anciano , Audiometría de Tonos Puros , Umbral Auditivo , Implantación Coclear/métodos , Sordera/fisiopatología , Sordera/cirugía , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Satisfacción del Paciente , Relación Señal-Ruido , Percepción del Habla , Voz , Adulto JovenRESUMEN
The present study investigates how electrically evoked Auditory Brainstem Responses (eABRs) can be used to measure local channel interactions along cochlear implant (CI) electrode arrays. eABRs were recorded from 16 experienced CI patients in response to electrical pulse trains delivered using three stimulation configurations: (1) single electrode stimulations (E11 or E13); (2) simultaneous stimulation from two electrodes separated by one (En and En+2, E11 and E13); and (3) stimulations from three consecutive electrodes (E11, E12, and E13). Stimulation level was kept constant at 70% electrical dynamic range (EDR) on the two flanking electrodes (E11 and E13) and was varied from 0 to 100% EDR on the middle electrode (E12). We hypothesized that increasing the middle electrode stimulation level would cause increasing local electrical interactions, reflected in characteristics of the evoked compound eABR. Results show that group averaged eABR wave III and V latency and amplitude were reduced when stimulation level at the middle electrode was increased, in particular when stimulation level on E12 reached 40, 70, and 100% EDR. Compound eABRs can provide a detailed individual quantification of electrical interactions occurring at specific electrodes along the CI electrode array. This approach allows a fine determination of interactions at the single electrode level potentially informing audiological decisions regarding mapping of CI systems.
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Facial nerve stimulation (FNS) is a potential complication which may affect the auditory performance of children with cochlear implants (CIs). We carried out an exploratory prospective observational study to investigate the effects of the electrical stimulation pattern on FNS reduction in young children with CI. Ten ears of seven prelingually deafened children with ages up to 6 years old who undergone a unilateral or bilateral CI surgery were included in this study. Electromyographic (EMG) action potentials from orbicularis oculi muscle were recorded using monopolar biphasic stimulation (ST1) and multi-mode monophasic stimulation with capacitive discharge (ST2). Presence of EMG responses, facial nerve stimulation thresholds (T-FNS) and EMG amplitudes were compared between ST1 and ST2. Intra-cochlear electrodes placement, cochlear-nerve and electrode-nerve distances were also estimated to investigate their effects on EMG responses. The use of ST2 significantly reduced the presence of intraoperative EMG responses compared to ST1. Higher stimulation levels were required to elicit FNS with ST2, with smaller amplitudes, compared to ST1. No and weak correlation was observed between cochlea-nerve and electrode-nerve distances and EMG responses, respectively. ST2 may reduce FNS in young children with CI. Differently from the electrical stimulation pattern, the cochlea-nerve and electrode-nerve distances seem to have limited effects on FNS in this population.
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Understanding cochlear anatomy is crucial for developing less traumatic electrode arrays and insertion guidance for cochlear implantation. The human cochlea shows considerable variability in size and morphology. This study analyses 1000+ clinical temporal bone CT images using a web-based image analysis tool. Cochlear size and shape parameters were obtained to determine population statistics and perform regression and correlation analysis. The analysis revealed that cochlear morphology follows Gaussian distribution, while cochlear dimensions A and B are not well-correlated to each other. Additionally, dimension B is more correlated to duct lengths, the wrapping factor and volume than dimension A. The scala tympani size varies considerably among the population, with the size generally decreasing along insertion depth with dimensional jumps through the trajectory. The mean scala tympani radius was 0.32 mm near the 720° insertion angle. Inter-individual variability was four times that of intra-individual variation. On average, the dimensions of both ears are similar. However, statistically significant differences in clinical dimensions were observed between ears of the same patient, suggesting that size and shape are not the same. Harnessing deep learning-based, automated image analysis tools, our results yielded important insights into cochlear morphology and implant development, helping to reduce insertion trauma and preserving residual hearing.
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INTRODUCTION: Electrically evoked auditory brainstem responses provide reliable clinical information to assist professionals in the auditory rehabilitation of cochlear implant users. OBJECTIVE: This study aimed to investigate intraoperative evoked auditory brainstem response recordings in Evo®-cochlear implant electrode array recipients and its correlation with their behavioral levels and auditory performance. METHODS: This is a retrospectivey study. Intraoperative evoked auditory brainstem responses were recorded in adult Evo®-cochlear implant electrode array recipients. Wave V latencies, amplitudes and interpeak III-V intervals were recorded in three different electrode locations and compared to the sentence recognition scores obtained from subjects after six months of device use. Evoked auditory brainstem responses thresholds were also recorded and compared to the behaviorally determined levels of the subjects in the sound processor activation. RESULTS: Evoked auditory brainstem responses thresholds were significantly correlated with both, behavioral T- and C-levels and they were recorded at audible electrical stimulation levels in all subjects. There was a significant correlation between interpeak III-V interval recorded in the apical electrode and sentence recognition scores of the subjects. CONCLUSIONS: Intraoperative evoked auditory brainstem responses can be used to establish audible levels for fitting the sound processor in Evo®-cochlear implant recipients and it could help professionals to plan further actions aiming to improve their auditory performance.
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BACKGROUND: A prospective longitudinal multicentre study was conducted to assess the one-year postsurgical hearing preservation profile of the EVOTM electrode array. METHODS: Fifteen adults presenting indications of electro-acoustic stimulation (pure-tone audiometry (PTA) thresholds ≤70 dB below 750 Hz) were implanted with the EVO™ electrode array. Hearing thresholds were collected at five time-points from CI activation to twelve months (12M) after activation. Hearing thresholds and hearing preservation profiles (HEARRING group classification) were assessed. RESULTS: All subjects had measurable hearing thresholds at follow-up. No case of complete loss of hearing or minimal hearing preservation was reported at any time point. At activation (Nact = 15), five participants had complete hearing preservation, and ten participants had partial hearing preservation. At the 12M time point (N12m = 6), three participants had complete hearing preservation, and three participants had partial hearing preservation. Mean hearing loss at activation was 11 dB for full range PTA and 25 dB for PTAs low-frequency (125-500 Hz). CONCLUSIONS: This study provides the first longitudinal follow-up on associated hearing profiles to the EVO™ electrode array, which are comparable to the literature. However, other studies on larger populations should be performed.
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The Oticon Medical Neuro cochlear implant system includes the modes Opti Omni and Speech Omni, the latter providing beamforming (i.e., directional selectivity) in the high frequencies. Two studies compared sentence identification scores of adult cochlear implant users with Opti Omni and Speech Omni. In Study 1, a double-blind longitudinal crossover study, 12 new users trialed Opti Omni or Speech Omni (random allocation) for three months, and their sentence identification in quiet and noise (+10 dB signal-to-noise ratio) with the trialed mode were measured. The same procedure was repeated for the second mode. In Study 2, a single-blind study, 11 experienced users performed a speech identification task in quiet and at relative signal-to-noise ratios ranging from -3 to +18 dB with Opti Omni and Speech Omni. The Study 1 scores in quiet and in noise were significantly better with Speech Omni than with Opti Omni. Study 2 scores were significantly better with Speech Omni than with Opti Omni at +6 and +9 dB signal-to-noise ratios. Beamforming in the high frequencies, as implemented in Speech Omni, leads to improved speech identification in medium levels of background noise, where cochlear implant users spend most of their day.
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Purpose For cochlear implant users, the ability to use the telephone is often seen as an important landmark during rehabilitation and an indicator of cochlear implant benefit. The goal of this study was to develop a short questionnaire exploring the ability to use the telephone in cochlear implant users, named Telislife, and test it in a group of experienced users. Method This prospective multicenter study was based on the completion of self-administrated questionnaires. The Telislife includes 20 items using a 5-point Likert scale for answers. Speech recognition scores were obtained with monosyllabic word lists at 70 dB HL. Quality of life was evaluated with the Nijmegen Cochlear Implant Questionnaire. This study included 55 adult patients wearing a cochlear implant for over 1 year. Results The Telislife questionnaire showed excellent reliability (Cronbach's α = .91). A significant correlation was found between Telislife scores and Nijmegen Cochlear Implant Questionnaire scores (r = .69, p < .001) and speech recognition scores (r = .35, p = .007). Conclusion Given significant correlations between Telislife scores and both speech recognition and quality of life and given its short form, the Telislife questionnaire appears to be a reliable tool to evaluate cochlear implant outcomes in clinical practice. Supplemental Material https://doi.org/10.23641/asha.13322873.
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Implantación Coclear , Implantes Cocleares , Percepción del Habla , Adulto , Humanos , Estudios Prospectivos , Calidad de Vida , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , TeléfonoRESUMEN
OBJECTIVE: The aim of the present study was to investigate the pupillary response to word identification in cochlear implant (CI) patients. Authors hypothesized that when task difficulty (i.e., addition of background noise) increased, pupil dilation markers such as the peak dilation or the latency of the peak dilation would increase in CI users, as already observed in normal-hearing and hearing-impaired subjects. METHODS: Pupillometric measures in 10 CI patients were combined to standard speech recognition scores used to evaluate CI outcomes, namely, speech audiometry in quiet and in noise at +10 dB signal-to-noise ratio (SNR). The main outcome measures of pupillometry were mean pupil dilation, maximal pupil dilation, dilation latency, and mean dilation during return to baseline or retention interval. Subjective hearing quality was evaluated by means of one self-reported fatigue questionnaire, and the Speech, Spatial, and Qualities (SSQ) of Hearing scale. RESULTS: All pupil dilation data were transformed to percent change in event-related pupil dilation (ERPD, %). Analyses show that the peak amplitudes for both mean pupil dilation and maximal pupil dilation were higher during the speech-in-noise test. Mean peak dilation was measured at 3.47 ± 2.29% noise vs. 2.19 ± 2.46 in quiet and maximal peak value was detected at 9.17 ± 3.25% in noise vs. 8.72 ± 2.93% in quiet. Concerning the questionnaires, the mean pupil dilation during the retention interval was significantly correlated with the spatial subscale score of the SSQ Hearing scale [r(8) = -0.84, p = 0.0023], and with the global score [r(8) = -0.78, p = 0.0018]. CONCLUSION: The analysis of pupillometric traces, obtained during speech audiometry in quiet and in noise in CI users, provided interesting information about the different processes engaged in this task. Pupillometric measures could be indicative of listening difficulty, phoneme intelligibility, and were correlated with general hearing experience as evaluated by the SSQ of Hearing scale. These preliminary results show that pupillometry constitutes a promising tool to improve objective quantification of CI performance in clinical settings.
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OBJECTIVE: This study investigated the audiological and tinnitus outcomes of cochlear implantation (CI) in adults with single-sided deafness (SSD) and tinnitus. STUDY DESIGN: Multicentered prospective, non-randomized intervention study. SETTING: Six French CI centers. PATIENTS: Twenty-six patients with SSD and incapacitating tinnitus (Tinnitus Handicap Inventory [THI] >58) underwent cochlear implantation. INTERVENTIONS: First, CIs delivered only masking white noise stimulation for 1 month and then standard CI stimulation. MAIN OUTCOME MEASURES: Before and after CI surgery, patients completed the THI, Tinnitus Reaction Questionnaire (TRQ), Subjective Tinnitus Severity Scale (STSS), and two visual analogue scales quantifying tinnitus loudness and annoyance. Speech perception in spatialized noise was tested at 13 months. RESULTS: The first month of white noise stimulation triggered a significant improvement in THI scores (72â±â9 to 55â±â20, pâ<â0.05). No change was observed for the other measures. After 1 year of standard CI stimulation, 23 patients (92%) reported a significant improvement in tinnitus. This improvement started 1 to 2 months after CI and exceeded 40% improvement for 14 patients (54%). Average speech-in-noise perception after 1 year significantly improved for the 23 patients who completed these measures. CONCLUSIONS: CI is efficacious to reduce the handicap of patient with SSD and incapacitating tinnitus, leading to a decrease in reported tinnitus and partial restoration of binaural hearing abilities.
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Implantación Coclear , Implantes Cocleares , Sordera , Pérdida Auditiva Unilateral , Percepción del Habla , Acúfeno , Adulto , Sordera/cirugía , Estudios de Seguimiento , Pérdida Auditiva Unilateral/cirugía , Humanos , Estudios Prospectivos , Acúfeno/cirugía , Resultado del TratamientoRESUMEN
OBJECTIVE: This prospective longitudinal cohort study at six tertiary referral centers in Canada and Denmark describes the clinical efficiency and surgical safety of cochlear implantation with the Oticon Medical Neuro cochlear implant system, including the Neuro Zti implant, the EVO electrode array, and the Neuro One sound processor. METHODS: Patients were adult cochlear implant candidates with bilateral sensorineural hearing loss. RESULTS: The mean HINT scores in quiet pre-operatively and at 3, 6, and 12 months post-activation were 13%, 58%, 67%, and 72%, respectively, and in noise (+10 dB SNR) 13%, 46%, 53%, and 59%, respectively. The mean improvement from baseline to 6 months post-activation was 54% in quiet and 40% in noise. The surgical major complication incidence rate was 0% and the post-surgical major complication incidence rate (until 12 months post-activation) was 4%. There was no adverse event that was fatal, that required explantation, or that resulted in sound processor nonuse, and no implant failure. CONCLUSION: Cochlear implantation with the Oticon Medical Neuro system enables speech identification both in quiet and in noise and audiologic outcomes continue to improve in the year following activation. No substantial adverse events occurred during the surgical implantation procedure and during the 12 months post-activation.
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Implantes Cocleares/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Implantación Coclear , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Ruido , Estudios Prospectivos , Resultado del TratamientoRESUMEN
PURPOSE: This study investigates the ability to understand degraded speech signals and explores the correlation between this capacity and the functional characteristics of the peripheral auditory system. METHOD: The authors evaluated the capability of 50 normal-hearing native French speakers to restore time-reversed speech. The task required them to transcribe two-syllable items containing temporal reversions of variable sizes, ranging from no reversion to complete reversion, increasing by half-syllable steps. In parallel, the functionality of each participant's auditory efferent system was evaluated using contralateral suppression of click-evoked otoacoustic emissions. RESULTS: Perceptual accuracy for time-reversed speech diminished when the size of the applied temporal distortion increased. A lexical benefit was evident, and an important interindividual variability in performance was observed. Functional exploration of the auditory system revealed that speech restoration performances correlated with the suppression strength of the participant's auditory efferent system. CONCLUSIONS: These results suggest a clear relation between the functional asymmetry of the auditory efferent pathway (the right-side activity is greater than the left-side activity in right-handed participants) and the comprehension of acoustically distorted speech in normal-hearing participants. Further experiments are needed to better specify how the functionality of the medial olivocochlear bundle can cause phonological activation to be more efficient.
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Comprensión/fisiología , Percepción del Habla/fisiología , Habla , Estimulación Acústica , Adolescente , Adulto , Análisis de Varianza , Femenino , Lateralidad Funcional , Humanos , Masculino , Emisiones Otoacústicas Espontáneas , Fonética , Psicoacústica , Factores de Tiempo , Vocabulario , Adulto JovenRESUMEN
Objective: To propose a method for quantitative assessment of the migration of lateral-wall, straight electrode arrays after surgery based on postoperative Cone Beam Computed Tomography (CBCT) images and automated medical image analysis techniques. Methods: A preliminary study is conducted on 19 implanted ears. For each implantation, two CBCT images are objectively analyzed. Electrode arrays are consistently projected into the same coordinate system in order to estimate precisely the migration of each electrode. Spatial configuration changes are characterized with the overall curvature of the electrode array. Results: From the samples analyzed no significant electrode migration, extrusion or electrode curvature changes were found. Mean infinitesimal local migration reveals a tendency where apical electrodes tend to move away from the modiolus and basal electrodes away from the round window. Conclusion: CBCT images demonstrate adequate resolution with limited artifacts to assess the electrode array position in vivo. Automated medical image analysis techniques and consistent coordinate system allow to quantitatively estimate migration and extrusion effect for lateral-wall, straight electrode array.
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Implantación Coclear , Implantes Cocleares , Tomografía Computarizada de Haz Cónico/métodos , Interpretación de Imagen Asistida por Computador/métodos , Falla de Prótesis , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Periodo Posoperatorio , Reproducibilidad de los ResultadosRESUMEN
OBJECTIVE: To evaluate quality of life (QoL) and cognitive function in elderly patients with cochlear implants relative to auditory improvement, using geriatric validated scales. STUDY DESIGN: Prospective observational study. SETTING: A tertiary referral center for cochlear implantation (CI) and a geriatric center in Nancy, France. PATIENTS: Sixteen consecutive patients were included, from 65 to 80 years old, with postlingual severe-to-profound deafness. MAIN OUTCOME MEASURES: Evaluations were conducted before and at 6 and 12 months after cochlear implant surgery. A monosyllabic word recognition test was used to measure speech perception. QoL was evaluated by the World Health Organization Quality of Life Assessment for elderly people; cognitive function was evaluated by the Mini-Mental State Examination; depression was evaluated by the Hamilton Scale; autonomy was evaluated by the Instrumental Activities of Daily Living. RESULTS: Speech intelligibility evolved from 10% before surgery to 63% and 69% at 6 and 12 months after cochlear implant activation, respectively. QoL showed significant improvement in sensory abilities. The Mini-Mental State Examination evaluations remained stable and executive functions tended to improve. Autonomy improved significantly. CONCLUSION: Cochlear implantation improves autonomy and the QoL in the elderly. Cognitive functions are not influenced by surgery, but executive functions appear to benefit from implantation. Age should not be a limiting factor, and cochlear implantation can be proposed as an efficient treatment for severe-to-profound hearing loss in the elderly.
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Implantación Coclear/psicología , Cognición/fisiología , Pérdida Auditiva/rehabilitación , Calidad de Vida , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Implantes Cocleares , Depresión/psicología , Femenino , Pérdida Auditiva/fisiopatología , Humanos , Masculino , Autonomía Personal , Estudios Prospectivos , Percepción del Habla/fisiologíaRESUMEN
Abstract Introduction Electrically evoked auditory brainstem responses provide reliable clinical information to assist professionals in the auditory rehabilitation of cochlear implant users. Objective This study aimed to investigate intraoperative evoked auditory brainstem response recordings in Evo®-cochlear implant electrode array recipients and its correlation with their behavioral levels and auditory performance. Methods This is a retrospectivey study. Intraoperative evoked auditory brainstem responses were recorded in adult Evo®-cochlear implant electrode array recipients. Wave V latencies, amplitudes and interpeak III-V intervals were recorded in three different electrode locations and compared to the sentence recognition scores obtained from subjects after six months of device use. Evoked auditory brainstem responses thresholds were also recorded and compared to the behaviorally determined levels of the subjects in the sound processor activation. Results Evoked auditory brainstem responses thresholds were significantly correlated with both, behavioral T- and C-levels and they were recorded at audible electrical stimulation levels in all subjects. There was a significant correlation between interpeak III-V interval recorded in the apical electrode and sentence recognition scores of the subjects. Conclusions Intraoperative evoked auditory brainstem responses can be used to establish audible levels for fitting the sound processor in Evo®-cochlear implant recipients and it could help professionals to plan further actions aiming to improve their auditory performance.
Resumo Introdução Os potenciais auditivos de tronco encefálico evocados eletricamente fornecem informações clínicas confiáveis que auxiliam no processo de reabilitação auditiva de usuários de implante coclear. Objetivo Investigar o registro intraoperatório dos potenciais auditivos de tronco encefálico evocados eletricamente em usuários do feixe de eletrodos Evo® e sua correlação com os níveis comportamentais e desempenho auditivo dos indivíduos. Método Estudo retrospectivo. Os potenciais auditivos de tronco encefálico intraoperatórios foram registrados em usuários adultos de implante coclear com feixe de eletrodos Evo®. As latências e amplitudes da onda V e os intervalos interpico III-V foram registrados em três diferentes eletrodos e comparados às pontuações de reconhecimento de sentenças após 6 meses de uso do implante coclear. Os limiares dos eABRs foram comparados aos níveis comportamentais dos indivíduos na ativação do processador de som. Resultados Os limiares do eABR foram significativamente correlacionados aos níveis comportamentais T e C e registrados em níveis de estimulação elétrica audíveis em todos os indivíduos. Houve uma correlação significativa entre o intervalo interpico III-V no eletrodo apical e a pontuação de reconhecimento de sentenças dos indivíduos. Conclusões O eABR intraoperatório pode ser usado para estabelecer níveis audíveis de estimulação elétrica na ativação do processador sonoro em usuários de implante coclear‐Evo® e pode auxiliar os profissionais no planejamento de ações visando melhorar o desempenho auditivo nesses pacientes.
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The current research provides a theoretical, computational and neurophysiological framework in which particular aspects of sentence comprehension and non-linguistic sequence transformation processing are implemented by a common neural mechanism for structure mapping. The theoretical context is derived from construction grammar theory in which language is considered in terms of a structured inventory of form to meaning mappings. Computationally, the construction grammar concept is implemented in a hybrid neural network model that is derived from functional neuroanatomical studies. In particular, based on data from Hoen et al. (2006, this issue), the generalized structure mapping capability is attributed to a local cortical network that includes Brodmann's area (BA) 44, while the integration of semantic structure into this transformation mechanism relies on BA 45.
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Mapeo Encefálico , Comprensión/fisiología , Modelos Neurológicos , Psicolingüística , Semántica , Encéfalo/anatomía & histología , Encéfalo/fisiología , HumanosRESUMEN
The determining of brain regions that exhibit specific activity during sentence comprehension compared to other non-linguistic cognitive tasks constitutes one of the important challenges in the domain of functional neuroimaging of the faculty of language. In the current paper we report an event-related functional magnetic resonance imaging (ER-fMRI) experiment, in which we directly compared the cerebral basis of sentence comprehension on the one hand, and of abstract sequence processing on the other hand. Previous experimental work done in our group, as well as different observations from recent behavioural, neurophysiological and functional neuroimaging experiments led us to propose the hypothesis that both of these tasks would share certain computational properties. Thus, this experiment was designed to show which brain regions would be implicated in both tasks and compare them to brain regions that would be specifically engaged in sentence comprehension. Results from this experiment suggest that distinct sub-regions in the left prefrontal cortex, potentially including Broca's area show distinct activation patterns during both of these tasks. Results are discussed in the context of a construction-based model of sentence processing (see Dominey and Hoen, 2006, this issue) that is based on a dual-path processing mechanism separating function and content information processing. We propose and discuss the hypothesis that subparts of Broca's area BA 44 and BA 45 would respectively be implicated in two different aspects of sentence comprehension: i) a general structure mapping capability and ii) the online integration of semantic representations onto structural constraints.
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Cognición/fisiología , Comprensión/fisiología , Lóbulo Frontal/fisiopatología , Adulto , Mapeo Encefálico , Corteza Cerebral/fisiología , Análisis por Conglomerados , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Neurológicos , Red Nerviosa/fisiología , Psicolingüística , Desempeño Psicomotor/fisiología , LecturaRESUMEN
A vast majority of dyslexic children exhibit a phonological deficit, particularly noticeable in phonemic identification or discrimination tasks. The gap in performance between dyslexic and normotypical listeners appears to decrease into adulthood, suggesting that some individuals with dyslexia develop compensatory strategies. Some dyslexic adults however remain impaired in more challenging listening situations such as in the presence of background noise. This paper addresses the question of the compensatory strategies employed, using the recently developed Auditory Classification Image (ACI) methodology. The results of 18 dyslexics taking part in a phoneme categorization task in noise were compared with those of 18 normotypical age-matched controls. By fitting a penalized Generalized Linear Model on the data of each participant, we obtained his/her ACI, a map of the time-frequency regions he/she relied on to perform the task. Even though dyslexics performed significantly less well than controls, we were unable to detect a robust difference between the mean ACIs of the two groups. This is partly due to the considerable heterogeneity in listening strategies among a subgroup of 7 low-performing dyslexics, as confirmed by a complementary analysis. When excluding these participants to restrict our comparison to the 11 dyslexics performing as well as their average-reading peers, we found a significant difference in the F3 onset of the first syllable, and a tendency of difference on the F4 onset, suggesting that these listeners can compensate for their deficit by relying upon additional allophonic cues.