Speech recognition in noise task among children and young-adults: a pupillometry study

IntroductionChildren experience unique challenges when listening to speech in noisy environments. The present study used pupillometry, an established method for quantifying listening and cognitive effort, to detect temporal changes in pupil dilation during a speech-recognition-in-noise task among school-aged children and young adults.MethodsThirty school-aged children and 31 young adults listened to sentences amidst four-talker babble noise in two signal-to-noise ratios (SNR) conditions: high accuracy condition (+10 dB and  + 6 dB, for children and adults, respectively) and low accuracy condition (+5 dB and + 2 dB, for children and adults, respectively). They were asked to repeat the sentences while pupil size was measured continuously during the task.ResultsDuring the auditory processing phase, both groups displayed pupil dilation; however, adults exhibited greater dilation than children, particularly in the low accuracy condition. In the second phase (retention), only children demonstrated increased pupil dilation, whereas adults consistently exhibited a decrease in pupil size. Additionally, the children’s group showed increased pupil dilation during the response phase.DiscussionAlthough adults and school-aged children produce similar behavioural scores, group differences in dilation patterns point that their underlying auditory processing differs. A second peak of pupil dilation among the children suggests that their cognitive effort during speech recognition in noise lasts longer than in adults, continuing past the first auditory processing peak dilation. These findings support effortful listening among children and highlight the need to identify and alleviate listening difficulties in school-aged children, to provide proper intervention strategies

The Effects of Psychophysical Methods on Spectral and Spatial TOJ Thresholds

(1) Background: A large number of studies have used different psychophysical methods for measuring temporal order judgment (TOJ) thresholds, which makes it difficult to compare the results of different studies. In this study, we aimed to compare the thresholds measured by the two main procedures used in many studies, the adaptive procedure, and the method of constant stimuli; (2) Methods: Study 1 tested spatial TOJ and included 109 participants, 50 using the adaptive procedure and 59 using the constant stimuli procedure. Study 2 tested spectral TOJ and included 223 participants, 119 using the adaptive procedure and 104 using constant stimuli; (3) Results: Both the spatial and spectral TOJ results showed no difference between the psychophysical methods, either in (1) the form of the distribution; (2) the mean; or (3) the standard deviation. However, Bayesian analysis showed a large Bayes factor only for spatial TOJ; (4) Conclusions: There is no difference between spatial TOJ thresholds measured by an adaptive procedure and the method of constant stimuli, and their results can be compared across studies. A similar conclusion can be drawn also for spectral TOJ, but should be considered more cautiously

Situational Awareness: The Effect of Stimulus Type and Hearing Protection on Sound Localization

The purpose of the current study was to test sound localization of a spoken word, rarely studied in the context of localization, compared to pink noise and a gunshot, while taking into account the source position and the effect of different hearing protection devices (HPDs) used by the listener. Ninety participants were divided into three groups using different HPDs. Participants were tested twice, under with- and no-HPD conditions, and were requested to localize the different stimuli that were delivered from one of eight speakers evenly distributed around them (starting from 22.5°). Localization of the word stimulus was more difficult than that of the other stimuli. HPD usage resulted in a larger mean root-mean-square error (RMSE) and increased mirror image reversal errors for all stimuli. In addition, HPD usage increased the mean RMSE and mirror image reversal errors for stimuli delivered from the front and back, more than for stimuli delivered from the left and right. HPDs affect localization, both due to attenuation and to limitation of pinnae cues when using earmuffs. Difficulty localizing the spoken word should be considered when assessing auditory functionality and should be further investigated to include HPDs with different attenuation spectra and levels, and to further types of speech stimuli

The Effect of Age, Type of Noise, and Cochlear Implants on Adaptive Sentence-in-Noise Task

Adaptive tests of sentences in noise mimic the challenge of daily listening situations. The aims of the present study were to validate an adaptive version of the HeBio sentence test on normal hearing (NH) adults; to evaluate the effect of age and type of noise on speech reception threshold in noise (SRTn); and to test it on prelingual adults with cochlear implants (CI). In Experiment 1, 45 NH young adults listened to two lists accompanied by four-talker babble noise (4TBN). Experiment 2 presented the sentences amidst 4TBN or speech-shaped noise (SSN) to 80 participants in four age groups. In Experiment 3, 18 CI adult users with prelingual bilateral profound hearing loss performed the test amidst SSN, along with HeBio sentences and monosyllabic words in quiet and forward digits span. The main findings were as follows: SRTn for NH participants was normally distributed and had high test–retest reliability; SRTn was lower among adolescents and young adults than middle-aged and older adults, and were better for SSN than 4TBN; SRTn for CI users was higher and more variant than for NH and correlated with speech perception tests in quiet, digits span, and age at first CI. This suggests that the adaptive HeBio can be implemented in clinical and research settings with various populations

Benefits of Auditory Training with an Open-Set Sentences-in-Babble-Noise

Auditory training (AT) has limited generalization to non-trained stimuli. Therefore, in the current study, we tested the effect of stimuli similar to that used in daily life: sentences in background noise. The sample consisted of 15 Hebrew-speaking adults aged 61–88 years with bilateral hearing impairment who engaged in computerized auditory training at home four times per week over a two-month period. Significant improvements were observed in sentences comprehension (Hebrew AzBio (HeBio) sentences test) with both four-talker-babble-noise (4TBN) and speech-shaped-noise (SSN) and in words comprehension (consonant-vowel-consonant (CVC) words test), following one month of AT. These improvements were sustained for two months after completing the AT. No evidence of spontaneous learning was observed in the month preceding training, nor was there an additional training effect in the additional month. Participants’ baseline speech perception abilities predicted their post-training speech perception improvements in the generalization tasks. The findings suggest that top-down generalization occurs from sentences to words and from babble noise to SSN and quiet conditions. Consequently, synthetic training tasks focusing on sentence-level comprehension accompanied by multi-talker babble noise should be prioritized. Moreover, an individualized approach to AT has demonstrated effectiveness and should be considered in both clinical and research settings