Susan Gordon-Hickey

The relationship of locus of control, self-control, and acceptable noise levels for young listeners with normal hearing

Abstract Objective: Background noise acceptance while listening to speech, assessed via the acceptable noise level (ANL) measure, has been shown to be an accurate predictor of hearing-aid success. No specific listener characteristics have been identified as being related to a listeners ability to accept background noise. The purpose of this study was to determine whether or not locus of control and self-control are related to ANL. Design: Correlational design. Study sample: Participants were seventy young adults (21 male, 49 female; aged 19 to 39 years) with normal hearing. Participants completed psychological profiles that evaluated locus of control and self-control and their ANLs were measured. Results: Results revealed correlations between ANL and self-control. Listeners with higher levels of self-control accepted more background noise than listeners with lower levels of self-control. Conclusions: This research suggests that exercises aimed at strengthening a listeners auditory self-control may lead to improved background noise acceptance. Improvement in background noise acceptance could lead to improved hearing-aid success. Future research should explore these possibilities.

Most comfortable listening levels, background noise levels, and acceptable noise levels for children and adults with normal hearing.

BACKGROUND For adults the acceptable noise level (ANL) has been shown to be a strong predictor of hearing aid success. ANL is calculated as the difference between most comfortable listening level (MCL) and background noise level (BNL). No studies have made direct comparisons of these measures between adults and children. PURPOSE To evaluate and compare MCLs, BNLs, and ANLs in children and young adults. RESEARCH DESIGN A cross-sectional design was used in this study. Two groups (children and adults) were tested for each dependent variable. MCLs and BNLs were measured for each participant, and ANLs were computed from these two measurements. STUDY SAMPLE The participants were 34 children (8-10 yr) and 34 young adults (19-29 yr) with normal hearing. RESULTS Significant main effects were found for MCLs and BNLs. There was no main effect for ANLs. MCLs and BNLs were significantly lower for the children than for the adults. CONCLUSIONS These results suggest that while ANLs are unchanged from childhood to adulthood, there appears to be a developmental change in MCLs and BNLs. These findings have implications for the use of ANLs in the pediatric population.

Effects of reverberation on acceptable noise level measurements in younger and older adults.

Abstract Acceptable noise level (ANL) test materials were digitally modified to create five reverberant conditions by applying different values of reverberation time (RT) to a non-reverberant condition (RT = 0, 0.4, 0.7, 1.2, and 2 s). Two groups of 12 subjects participated: younger individuals (22–29 years, M = 24.3) and older adults (50–69 years, M = 57.5). Mean hearing threshold levels (250 to 8000 Hz) for both groups were 30 dB HL or better. Most comfortable listening level (MCL) and background noise level (BNL) measurements were completed in each reverberant condition, and from these measurements, ANLs were calculated. Significant main effects for age and reverberation were not found for ANL or MCL. These results suggest that reverberation does not affect the amount of background noise individuals are willing to accept, or the level of speech individuals choose as the MCL. These results can be used by clinical audiologists to counsel patients regarding the use of communication strategies. Additionally, these results can be used to support previous findings that ANL is not related to the intelligibility of the speech signal. Sumario Se modificaron digitalmente materiales de prueba de niveles aceptables de ruido (ANL) para crear cinco condiciones de reverberación, aplicando diferentes valores de tiempo de reverberación (RT) a una condición no reverberante (RT = 0, 0.4, 0.7, 1.2, y 2 s). Participaron dos grupos de 12 sujetos: jóvenes (22–29 años, M = 24.3) y adultos mayores (50–69 años, M = 57.5). La media de los umbrales auditivos (250 a 8000 Hz) en ambos grupos fue de 30 dB HL o mejor. El mejor nivel confortable de audición (MCL) y las mediciones del nivel de ruido de fondo (BNL) se completaron en cada condición de reverberación y de estas mediciones, se calcularon los ANL. No se encontraron efectos significativos por edad y reverberación para el ANL o el MCL. Estos resultados sugieren que la reverberación no afecta la cantidad de ruido de fondo que los individuos stán dispuestos a aceptar ni el nivel de lenguaje que seleccionan como el MCL. Estos resultados pueden ser usados por los audiólogos clínicos para aconsejar a los pacientes en relación con el uso de estrategias comunicativas. Adicionalmente, pueden usarse para apoyar hallazgos previos en cuanto a que los ANL no se relacionan con la inteligibilidad de las señales del habla.

Speech Recognition at the Acceptable Noise Level.

BACKGROUND The acceptable noise level (ANL) has been proposed as a prehearing aid fitting measure that could be used for hearing aid selection and counseling purposes. Previous work has demonstrated that a listeners ANL is unrelated to their speech recognition in noise abilities. It is unknown what criteria a listener uses when they select their ANL. To date, no research has explored the amount of speech recognized at the listeners ANL. PURPOSE To examine the amount of speech recognized at the listeners ANL to determine whether speech recognition in noise is utilized as a factor for setting ANL. RESEARCH DESIGN A descriptive quasi-experimental study was completed. For all listeners, ANL was measured and speech recognition in noise was tested at ANL and at two additional signal-to-noise ratio (SNR) conditions based on the listeners ANL (ANL + 5 and ANL - 5). STUDY SAMPLE Forty-four older adults served as participants. Twenty-seven participants had normal hearing and seventeen participants had mild to moderately-severe, symmetrical, sensorineural hearing loss. DATA COLLECTION AND ANALYSIS Acceptance of noise was calculated from the measures of most comfortable listening level and background noise level. Additionally, speech recognition in noise was assessed at three SNRs using the quick speech-in-noise test materials. RESULTS A significant interaction effect of SNR condition and ANL group occurred for speech recognition. At ANL, a significant difference in speech recognition in noise was found across groups. Those in the mid and high ANL groups had excellent speech recognition at their ANL. Speech recognition in noise at ANL decreased with ANL category. CONCLUSIONS For listeners with mid and high ANLs, speech recognition appears to play a primary role in setting their ANL. For those with low ANLs, speech recognition may contribute to setting their ANL; however, it does not appear to be the primary determiner of ANL. For those with very low ANLs, speech recognition does not appear to be significant variable for setting their ANL.

The Influence of Speech Rate on Acceptable Noise Levels

BACKGROUND Older adults often struggle with accurate perception of rate-altered speech and have difficulty understanding speech in noise. The acceptable noise level (ANL) quantifies a listeners willingness to listen to speech in background noise and has been found to accurately predict hearing aid success. Based on the difficulty older adults experience with rapid speech, we were interested in how older adults may change the amount of background noise they willingly accept in a variety of speech rate conditions. PURPOSE To determine the effects of age and speech rate on the ANL. RESEARCH DESIGN A quasi-experimental mixed design was employed. STUDY SAMPLE Fifteen young adults (19-27 yr) and fifteen older adults (55-73 yr) with audiometrically normal hearing or hearing loss within age-normed limits served as participants. DATA COLLECTION AND ANALYSIS Most comfortable listening levels (MCLs) and background noise levels (BNLs) were measured using three different speech rates (slow, normal, and fast). The ANL was calculated by subtracting BNL from MCL. Repeated measures analysis of variances were used to analyze the effects of age and speech rate on ANL. RESULTS A significant main effect of speech rate was observed; however, a significant main effect of age was not found. Results indicated that as speech rate increased the ANLs increased. This suggests that participants became less accepting of background noise as speech rates increased. CONCLUSIONS The findings of the present study provide support for communication strategies that recommend slowing an individuals speaking rate and/or reducing background noise, if possible. Participants in the present study were better able to cope with background noise when the primary stimulus was presented at slow and normal speaking rates.