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Background: An important goal of providing amplification to children with hearing loss is to ensure that hearing aids are adjusted to match targets of prescriptive procedures as closely as possible. The Desired Sensation Level (DSL) v5 and the National Acoustic Laboratories’ prescription for nonlinear hearing aids, version 1 (NAL-NL1) procedures are widely used in fitting hearing aids to children. Little is known about hearing aid fitting outcomes for children with severe or profound hearing loss. Purpose: The purpose of this study was to investigate the prescribed and measured gain of hearing aids fit according to the NAL-NL1 and the DSL v5 procedure for children with moderately severe to profound hearing loss; and to examine the impact of choice of prescription on predicted speech intelligibility and loudness. Research Design: Participants were fit with Phonak Naida V SP hearing aids according to the NAL-NL1 and DSL v5 procedures. The Speech Intelligibility Index (SII) and estimated loudness were calculated using published models. Study Sample: The sample consisted of 16 children (30 ears) aged between 7 and 17 yr old. Data Collection and Analysis: The measured hearing aid gains were compared with the prescribed gains at 50 (low), 65 (medium), and 80 dB SPL (high) input levels. The goodness of fit-to-targets was quantified by calculating the average root-mean-square (RMS) error of the measured gain compared with prescriptive gain targets for 0.5, 1, 2, and 4 kHz. The significance of difference between prescriptions for hearing aid gains, SII, and loudness was examined by performing analyses of variance. Correlation analyses were used to examine the relationship between measures. Results: The DSL v5 prescribed significantly higher overall gain than the NAL-NL1 procedure for the same audiograms. For low and medium input levels, the hearing aids of all children fit with NAL-NL1 were within 5 dB RMS of prescribed targets, but 33% (10 ears) deviated from the DSL v5 targets by more than 5 dB RMS on average. For high input level, the hearing aid fittings of 60% and 43% of ears deviated by more than 5 dB RMS from targets of NAL-NL1 and DSL v5, respectively. Greater deviations from targets were associated with more severe hearing loss. On average, the SII was higher for DSL v5 than for NAL-NL1 at low input level. No significant difference in SII was found between prescriptions at medium or high input level, despite greater loudness for DSL v5 than for NAL-NL1. Conclusions: Although targets between 0.25 and 2 kHz were well matched for both prescriptions in commercial hearing aids, gain targets at 4 kHz were matched for NAL-NL1 only. Although the two prescriptions differ markedly in estimated loudness, they resulted in comparable predicted speech intelligibility for medium and high input levels.

Many adults who receive a cochlear implant in one ear have usable residual hearing in the opposite ear. The simultaneous use of a cochlear implant (CI) and a hearing aid (HA) in the contralateral ear, or bimodal fitting, provides the recipient with potentially complementary information to the auditory system for speech perception, localization, and functional benefits in everyday life via two different modes of stimulation (acoustic and electric). This study investigated consonant perception in listeners who use bimodal fitting with the aim to identify the acoustic cues responsible for speech understanding when an HA is used together with a CI in comparison with the use of a CI alone. The results showed that on average, there was significant improvement in consonant recognition in quiet and in noise when adults wore CIs with HAs compared with CIs alone. Feature analysis of consonants was performed to directly examine what additional cues were provided by the HA to enhance consonant perception. This analysis showed that on average, there was a significant increase in reception of information about voicing in quiet conditions and about voicing and manner of articulation in noise. There was no difference in the transmission of information about place of articulation. The implications of these findings on rehabilitation of adults with unilateral CI are discussed.

Finding ways to evaluate the success of hearing aid fittings in young infants has increased in importance with the implementation of hearing screening programs. Cortical auditory evoked potentials (CAEP) can be recorded in infants and provides evidence for speech detection at the cortical level. The validity of this technique as a tool of hearing aid evaluation needs, however, to be demonstrated. The present study examined the relationship between the presence/absence of CAEPs to speech stimuli and the outcomes of a parental questionnaire in young infants who were fitted with hearing aids. The presence/absence of responses was determined by an experienced examiner as well as by a statistical measure, Hotelling's T2. A statistically significant correlation between CAEPs and questionnaire scores was found using the examiner's grading (rs = 0.45) and using the statistical grading (rs = 0.41), and there was reasonably good agreement between traditional response detection methods and the statistical analysis. La búsqueda de formas de evaluar el éxito de una adaptación de auxiliares auditivos en niños pequeños ha aumentado en importancia con la implementación de los programas de tamizaje auditivo. Se pueden registrar potenciales evocados auditivos corticales (CAEP) en infantes y aportar evidencia sobre la detección del lenguaje a nivel cortical. La validez de esta técnica como una herramienta para la evaluación de las necesidades de adaptación de auxiliares auditivos necesita, sin embargo, ser demostrada. El presente estudio examinó la relación entre la presencia/ausencia de CAEP ante estímulos de lenguaje y el resultado de un cuestionario a los padres de infantes a los que se adaptaron auxiliares auditivos. La presencia/ausencia de respuestas fue determinada por un examinador con experiencia, así como por un procedimiento de medición estadística: la T2 de Hotelling. Se encontró una correlación estadísticamente significativa entre los CAEP y los puntajes del cuestionario, utilizando la gradación del examinador (rs = 0.45) y utilizando la gradación estadística (rs = 0.41), y existió un acuerdo razonablemente bueno entre los métodos tradicionales de detección de respuesta y el análisis estadístico.