Stabilitet för Acceptable Noise Level (ANL) hos normalhörande vuxna personer vid upprepade mätningar inom samma testsession och dess

Olika personer har olika acceptans för bakgrundsbrus vid samtidig lyssning till tal. Akustiska parametrar och sensoriska aspekter har hittills inte kunnat förklara variationen. Högre funktioner som t.ex. arbetsminne tros vara en av de bakomliggande mekanismerna men orsakerna är inte väl utredda. Testet Acceptable Noise Level (ANL) mäter acceptans för bakgrundsbrus men spridningen av resultat på ANL-testet är stor. Denna undersökning genomförde upprepade mätningar av acceptabel brusnivå inom samma testsession samt arbetsminnestester för att se om stabiliteten för upprepade ANL-mätningar tillsammans med arbetsminneskapaciteten kunde bidra till att förklara variationen. Arbetsminnestesterna som genomfördes mätte fonologiskt och visuospatialt arbetsminne. Vissa individer visade sig vara mer stabila än andra, men graden av stabilitet på ANL-testet kunde inte förklaras av resultatet på de utförda arbetsminnestesterna. En ökande stabilitet med antalet ANL-mätningar skulle kunna bero på en inlärningseffekt. Testet har låg reliabilitet pga. svagheter i metoden och därför är det svårt att dra några tydliga slutsatser från undersökningen. Förslag på metodologiska förbättringar ges

Hearing thresholds and cognitive flexibility in young healthy individuals with normal hearing

Objective: Pure tone audiometry may seem to be a relatively easy task for the participant but it may involve cognitive as well as sensory abilities. The aim of this study is to examine the relationship between hearing thresholds in the frequency range 0.125–8 kHz and the core executive function cognitive flexibility in healthy individuals with normal hearing. Design: Experimental study measuring correlations between different pure-tone hearing threshold measures and cognitive flexibility. Pure tone air conduction audiometry (frequencies 0.125–8.0 kHz) and two tests of cognitive flexibility (information updating and shifting ability) were conducted. Study sample: Seventy-two subjects (aged between 21 and 36) with normal hearing (<20 dB HL) for the tested frequencies. Results: Four measures of average pure tone hearing thresholds were negatively correlated with cognitive flexibility. Conclusions: Pure-tone air conduction hearing thresholds seem to be related to cognitive flexibility in healthy individuals with normal hearing

The acceptable noise level: The effect of repeated measurements.

Objective: This study explores if increasing number of repetitions might improve the precision of the acceptable noise level (ANL) test. Design: We measured twelve ANL repetitions, i.e. four complete ANL tests (4 × 3 repetitions), at one session using diotic presentation and a non-semantic ANL version. Study sample: Thirty-two normal-hearing adults. Results: Small order and fatigue effects were seen. We used the coefficient of repeatability (CR) to assess the repeatability; CRs ranged between 3.9 and 7.6 dB for the four ANL tests. Using the twelve ANL repetitions we removed the variability of the ANL across subjects by normalizing the data to the individual mean ANL for the twelve repetitions. The mean normalized ANL across the subjects rapidly approached the ANL normalized to the individual mean for the 12 repetitions (0 dB), and after three repetitions the SD seemed to be stable at about 3 dB. Conclusions: The findings suggest that both order and fatigue affect the ANL. The findings also suggest that it may be more accurate to speak of an acceptable noise range than ANL. These findings have large implications for how we understand acceptable noise and it would explain a large part of the variability seen among normal-hearing and perhaps hearing-impaired subjects

Listening effort : Order effects and core executive functions

Background: Listening effort seems to depend on input-related listening demands and several factors internal to the individual listener. Input-related demands may be listening in noise compared with listening in quiet, and internal factors may be cognitive functions. Purpose: The purpose was to apply measures of listening effort and perceived listening effort in participants with normal hearing, to determine if there are any presentation order effects, and to explore the relationship between listening effort measured as accuracy, response times, efficiency of information encoding into long-term memory, perceived listening effort, and core executive functions. Research design: A within-subject design with repeated measures was used and a study of relationships between variables was made. Study sample: Thirty-two healthy adults with normal hearing. Data collection and analysis: Participants were tested individually by a listening task using a dual-task paradigm. The listening task was performed in quiet and in multitalker babble noise at 10 dB signal-to-noise ratio (SNR). Perceived listening effort and core executive functions (working memory, inhibitory control, and cognitive flexibility) were also assessed. Results: The measures of listening effort (correct responses, response times, and immediate and delayed listening comprehension) failed to demonstrate increased listening effort in multitalker babble noise (10 dB SNR) compared with quiet, although a significant test order effect was seen for correct responses indicating that participants who first listened in noise did not improve in quiet. Perceived listening effort increased significantly in noise compared with quiet. No relationship was found between measures of listening effort and ratings of perceived listening effort. Working memory and cognitive flexibility were not related to ratings of perceived listening effort. In contrast, better inhibitory control was related to higher ratings in both quiet and in noise. Conclusions: It is possible that the SNR and measures used were not as sensitive as required to measure listening effort behaviorally. In the present experimental setup, prior noise exposure impedes the beneficial effects of performing a task in quiet. Self-reports seem to provide a valid measure of perceived listening effort that is related to the individual's inhibitory control. The present findings suggest that participants with better inhibitory control are more susceptible to the task demand level both in quiet and in noise

Extended high-frequency pure tone hearing thresholds and core executive functions

Objective: To examine the relationship between extended high-frequency pure tone hearing thresholds (frequencies 10 to 14 kHz) and working memory capacity (WMC), inhibitory control, and cognitive flexibility. Design: Experimental study measuring correlations between different high-frequency hearing threshold measures and cognitive measures. Study: Pure tone audiometry was assessed in the extended high-frequency (frequencies 10, 12.5 and 14 kHz). Subjects were also tested regarding WMC, inhibitory control (response inhibition), and cognitive flexibility (information updating and shifting ability). Sample: Forty-three subjects between 20 and 29 years old with normal hearing (≤ 20 dB HL) in the frequency range between 0.125 to 8 kHz. Results: No significant correlations were seen between high-frequency hearing thresholds defined as average best and worst ear high-frequency hearing thresholds and the cognitive measures. Differences between the best and the worst ear showed significant negative correlations with inhibitory control and global executive function (combination score for WMC, inhibitory control and cognitive flexibility). Conclusions: The present study suggests that global executive functions, more specifically response inhibition, and hearing threshold asymmetry in the extended high-frequency range are interrelated

Should the acceptable noise level be considered to be an acceptable noise range?

The acceptable noise level (ANL) test is used to quantify the amount of competing background noise (BNL) that a listener is willing to accept when listening to speech at the most comfortable level (MCL). ANL is calculated by subtracting the BNL from the MCL. Most studies show large intersubject ANL variability and a few also demonstrate large intrasubject variability. Very few predictor variables for ANL have been identified and it has been proposed that the ANL depends on an inherent characteristic of the listener. However, some of the variability seems to depend on poor precision of the ANL test. After removing the effect of poor precision, some variability still remains. One possible explanation for these findings may be that the ANL is not a single level but a range of levels. Using recent data, this presentation examines the notion of an acceptable noise range

The effect of repeated measurements and working memory on the most comfortable level in the ANL test.

Objective: To study the effect of a large number of repetitions on the most comfortable level (MCL) when doing the acceptable noise level (ANL) test, and explore if MCL variability is related to central cognitive processes. Design: Twelve MCL repetitions were measured within the ANL test using interleaved methodology during one session using a non-semantic version. Phonological (PWM) and visuospatial working memory (VSWM) was measured. Study sample: Thirty-two normal-hearing adults. Results: Repeated measures ANOVA, intraclass correlations, and the coefficient of repeatability (CR) were used to assess the repeatability. Repeated measures ANOVA and CR indicated poor agreement between the two first repetitions. After excluding the first repetition, analyses showed that the MCL in the ANL test is reliable. A negative association was found between PWM and MCL variability indicating that subjects with higher PWM show less variability. Conclusions: The findings suggest that, after excluding the first repetition, the MCL in the ANL test is reliable. A single repetition of the MCL in the ANL test should be avoided. If an interleaved methodology is used, a single ANL repetition should be added prior to the actual testing. The findings also suggest that MCL variability is associated to PWM but not VSWM

The effect of voice quality and competing speakers in a passage comprehension task : perceived effort in relation to cognitive functioning and performance in children with normal hearing

The study investigates the effect of voice quality and competing speakers on perceived effort in a passage comprehension task in relation to cognitive functioning. In addition, it explores if perceived effort was related to performance. A total of 49 children (aged 7:03 to 12:02 years) with normal hearing participated. The children performed an auditory passage comprehension task presented with six different listening conditions consisting of a typical voice or a dysphonic voice presented in quiet, with one competing speaker, and with four competing speakers. After completing the task, they rated their perceived effort on a five-grade scale. The children also performed tasks measuring working memory capacity (WMC) and executive functioning. The results show that voice quality had no direct effect on perceived effort but the children’s ratings of perceived effort were related to their executive functioning. A significant effect was seen for background listening condition indicating higher perceived effort for background listening conditions with competing speakers. The effects of background listening condition were mainly related to the children’s WMC but also their executive functioning. It can be concluded that the individual susceptibility to the effect of the dysphonic voice is related to the child’s executive functioning. The individual susceptibility to the presence of competing speakers is related to the child’s WMC and executive functioning

The effect of voice quality and competing speakers in a passage comprehension task : performance in relation to cognitive functioning in children with normal hearing

Objective: This study explores the effect of voice quality and competing speaker/-s on children’s performance in a passage comprehension task. Furthermore, it explores the interaction between passage comprehension and cognitive functioning. Methods: Forty-nine children (27 girls and 22 boys) with normal hearing (aged 7–12 years) participated. Passage comprehension was tested in six different listening conditions; a typical voice (non-dysphonic voice) in quiet, a typical voice with one competing speaker, a typical voice with four competing speakers, a dysphonic voice in quiet, a dysphonic voice with one competing speaker, and a dysphonic voice with four competing speakers. The children’s working memory capacity and executive functioning were also assessed. Results: The findings indicate no direct effect of voice quality on the children’s performance, but a significant effect of background listening condition. Interaction effects were seen between voice quality, background listening condition, and executive functioning. Conclusions: The children’s susceptibility to the effect of the dysphonic voice and the background listening conditions are related to the individual’s executive functions. The findings have several implications for design of interventions in language learning environments such as classrooms