Objective The goal of this study was to establish the developmental trajectories for children’s open-set recognition of monosyllabic words in each of two maskers: two-talker speech and speech-shaped noise. Design Listeners were 56 children (5 to 16 yrs) and 16 adults, all with normal hearing. Thresholds for 50% correct recognition of monosyllabic words were measured in a two-talker speech or a speech-shaped noise masker in the sound field using an open-set task. Target words were presented at a fixed level of 65 dB SPL throughout testing, while the masker level was adapted. A repeated-measures design was used to compare the performance of three age groups of children (5 to 7 yrs, 8 to 12 yrs, and 13 to 16 yrs) and a group of adults. The pattern of age-related changes during childhood was also compared between the two masker conditions. Results Listeners in all four age groups performed more poorly in the two-talker speech than the speech-shaped noise masker, but the developmental trajectories differed for the two masker conditions. For the speech-shaped noise masker, children’s performance improved with age until about 10 years of age, with little systematic child-adult differences thereafter. In contrast, for the two-talker speech masker, children’s thresholds gradually improved between 5 and 13 years of age, followed by an abrupt improvement in performance to adult-like levels. Children’s thresholds in the two masker conditions were uncorrelated. Conclusions Younger children require a more advantageous signal-to-noise ratio than older children and adults to achieve 50% correct word recognition in both masker conditions. However, children’s ability to recognize words appears to take longer to mature and follows a different developmental trajectory for the two-talker speech masker than the speech-shaped noise masker. These findings highlight the importance of considering both age and masker type when evaluating children’s masked speech perception abilities.

Purpose This study evaluated child-adult differences for consonant identification in a noise or a two-talker masker. Error patterns were compared across age and masker type to test the hypothesis that errors with the noise masker reflect limitations in the peripheral encoding of speech, whereas errors with the two-talker masker reflect target-masker confusions within the central auditory system. Method A repeated-measures design compared the performance of children (5–13 years) and adults in continuous speech-shaped noise or a two-talker masker. Consonants were identified from a closed set of 12 using a picture-pointing response. Results In speech-shaped noise, children under 10 years of age performed more poorly than adults, but performance was adult-like for 11- to 13-year-olds. In the two-talker masker significant child-adult differences were observed in even the oldest group of children. Systematic clusters of consonant errors were observed for children in the noise masker and for adults in both maskers, but not for children in the two-talker masker. Conclusions These results suggest a more prolonged time course of development for consonant identification in a two-talker than in a noise masker. Differences in error patterns between the maskers support the hypothesis that errors with the two-talker masker reflect failures of sound segregation.

Children perform more poorly than adults on a wide range of masked speech perception paradigms, but this effect is particularly pronounced when the masker itself is also composed of speech. The present study evaluated two factors that might contribute to this effect: the ability to perceptually isolate the target from masker speech, and the ability to recognize target speech based on sparse cues (glimpsing). Speech reception thresholds (SRTs) were estimated for closed-set, disyllabic word recognition in children (5-16 years) and adults in a one-or two-talker masker. Speech maskers were 60 dB sound pressure level (SPL), and they were either presented alone or in combination with a 50-dB-SPL speech-shaped noise masker. There was an age effect overall, but performance was adult-like at a younger age for the one-talker than the two-talker masker. Noise tended to elevate SRTs, particularly for older children and adults, and when summed with the one-talker masker. Removing timefrequency epochs associated with a poor target-to-masker ratio markedly improved SRTs, with larger effects for younger listeners; the age effect was not eliminated, however. Results were interpreted as indicating that development of speech-in-speech recognition is likely impacted by development of both perceptual masking and the ability recognize speech based on sparse cues.

Objectives: The objectives of this study were to (1) evaluate the extent to which school-age children benefit from fundamental frequency (F0) differences between target words and competing two-talker speech, and (2) assess whether this benefit changes with age. It was predicted that while children would be more susceptible to speech-in-speech masking compared to adults, they would benefit from differences in F0 between target and masker speech. A second experiment was conducted to evaluate the relationship between frequency discrimination thresholds and the ability to benefit from target/masker differences in F0. Design: Listeners were children (5-15 years) and adults (20-36 years) with normal hearing. In the first experiment, speech recognition thresholds (SRTs) for disyllabic words were measured in a continuous, 60-dB-SPL two-talker speech masker. The same male talker produced both the target and masker speech (average F0 = 120 Hz). The level of the target words was adaptively varied to estimate the level associated with 71% correct identification. The procedure was a four-alternative forced-choice with a picture-pointing response. Target words either had the same mean F0 as the masker or it was shifted up by 3, 6 or 9 semitones. To determine the benefit of target/masker F0 separation on word recognition, masking release was computed by subtracting thresholds in each shifted-F0 condition from the threshold in the unshifted-F0 condition. In the second experiment, frequency discrimination thresholds were collected for a subset of listeners to determine whether sensitivity to F0 differences would be predictive of SRTs. The standard was the syllable /ba/ with an F0 of 250 Hz; the target stimuli had a higher F0. Discrimination thresholds were measured using a three-alternative, three-interval forced choice procedure. Results: Younger children (5-12 years) had significantly poorer SRTs than older children (13-15 years) and adults in the unshifted-F0 condition. The benefit of F0 separations generally increased with increasing child age and magnitude of target/masker F0 separation. For 5-to 7-year-olds, there was a small benefit of F0 separation in the 9-semitone condition only. For 8-to 12-year-olds, there was a benefit from both 6-and 9-semitone separations, but to a lesser degree than what was observed for older children (13-15 years

This study examined the degree to which masker-spectral variability contributes to children's susceptibility to informational masking. Listeners were younger children (5-7 years), older children (8-10 years), and adults (19-34 years). Masked thresholds were measured using a 2IFC, adaptive procedure for a 300-ms, 1000-Hz signal presented simultaneously with (1) broadband noise, (2) a random-frequency ten-tone complex, or (3) a fixed-frequency ten-tone complex. Maskers were presented at an overall level of 60 dB SPL. Thresholds were similar across age for the noise condition. Thresholds for most children were higher than for most adults, however, for both ten-tone conditions. The average difference in threshold between random and fixed ten-tone conditions was comparable across age, suggesting a similar effect of reducing masker-spectral variability in children and adults. Children appear more likely to be susceptible to informational masking than adults, however, both with and in the absence of masker-spectral variability. The addition of a masker fringe (delayed onset of signal relative to masker) provided a release from masking for fixed and random ten-tone conditions in all age groups, suggesting at least part of the masking observed for both ten-tone maskers was informational.