Effect of Spectral Channels on Speech Recognition, Comprehension, and Listening Effort in Cochlear-Implant Users

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Meta-Analysis on the Identification of Linguistic and Emotional Prosody in Cochlear Implant Users and Vocoder Simulations

Objectives: This study quantitatively assesses how cochlear implants (CIs) and vocoder simulations of CIs influence the identification of linguistic and emotional prosody in nontonal languages. By means of meta-analysis, it was explored how accurately CI users and normal-hearing (NH) listeners of vocoder simulations (henceforth: simulation listeners) identify prosody compared with NH listeners of unprocessed speech (henceforth: NH listeners), whether this effect of electric hearing differs between CI users and simulation listeners, and whether the effect of electric hearing is influenced by the type of prosody that listeners identify or by the availability of specific cues in the speech signal. Design: Records were found by searching the PubMed Central, Web of Science, Scopus, Science Direct, and PsycINFO databases (January 2018) using the search terms “cochlear implant prosody” and “vocoder prosody.” Records (published in English) were included that reported results of experimental studies comparing CI users’ and/or simulation listeners’ identification of linguistic and/or emotional prosody in nontonal languages to that of NH listeners (all ages included). Studies that met the inclusion criteria were subjected to a multilevel random-effects meta-analysis. Results: Sixty-four studies reported in 28 records were included in the meta-analysis. The analysis indicated that CI users and simulation listeners were less accurate in correctly identifying linguistic and emotional prosody compared with NH listeners, that the identification of emotional prosody was more strongly compromised by the electric hearing speech signal than linguistic prosody was, and that the low quality of transmission of fundamental frequency (f0) through the electric hearing speech signal was the main cause of compromised prosody identification in CI users and simulation listeners. Moreover, results indicated that the accuracy with which CI users and simulation listeners identified linguistic and emotional prosody was comparable, suggesting that vocoder simulations with carefully selected parameters can provide a good estimate of how prosody may be identified by CI users. Conclusions: The meta-analysis revealed a robust negative effect of electric hearing, where CIs and vocoder simulations had a similar negative influence on the identification of linguistic and emotional prosody, which seemed mainly due to inadequate transmission of f0 cues through the degraded electric hearing speech signal of CIs and vocoder simulations

Perception of L2 lexical stress in words degraded by a cochlear implant simulation

This study investigates how the perception of L2 lexical stress is affected by an acoustic simulation of cochlear implants (CIs). We explore whether Dutch L2 learners of English are influenced by f0 differences or a vowel quality contrast when identifying lexical stress in L2 English words degraded by a CI simulation and whether listeners transfer cue-weighting strategies of the L1 into the L2. Results indicate that the identification of lexical stress based on a five-by-two matrix varying in f0 and vowel quality was, as hypothesized, strongly compromised in the CI simulation, but that the lexical stress identification strategies for neither the unprocessed nor the CI-simulated stimuli differed between L1 Dutch and L2 English. This suggests that the lexical stress identification strategies of the L1 may have been transferred into the L2 and that the CI simulation of the present study affected L1 Dutch and L2 English lexical stress perception similarly

Speech Prosody:The Musical, Magical Quality of Speech

When we speak, we can vary how we use our voices. Our speech can be high or low (pitch), loud or soft (loudness), and fast or slow (duration). This variation in pitch, loudness, and duration is called speech prosody. It is a bit like making music. Varying our voices when we speak can express sarcasm or emotion and can even change the meaning of what we are saying. So, speech prosody is a crucial part of spoken language. But how do speakers produce prosody? How do listeners hear and understand these variations? Is it possible to hear and interpret prosody in other languages? And what about people whose hearing is not so good? Can they hear and understand prosodic patterns at all? Let’s find out

Prosodic Focus Interpretation in Spectrotemporally Degraded Speech by Non-Native Listeners

Purpose: This study assesses how spectrotemporal degradations that can occur in the sound transmission of a cochlear implant (CI) may influence the ability of non-native listeners to recognize the intended meaning of utterances based on the position of the prosodically focused word. Previous research suggests that perceptual accuracy and listening effort are negatively affected by CI processing (or CI simulations) or when the speech is presented in a non-native language, in a number of tasks and circumstances. How these two factors interact to affect prosodic focus interpretation, however, remains unclear.Method: In an online experiment, normal-hearing (NH) adolescent and adult native Dutch learners of English and a small control group of NH native English adolescents listened to CI-simulated (eight-channel noise-band vocoded) and non–CI-simulated English sentences differing in prosodically marked focus. For assessing perceptual accuracy, listeners had to indicate which of four possible context questions the speaker answered. For assessing listening effort, a dual-task paradigm was used with a secondary free recall task.Results: The results indicated that prosodic focus interpretation was significantly less accurate in the CI-simulated condition compared with the non–CI-simulated condition but that listening effort was not increased. Moreover, there was no interaction between the influence of the degraded CI-simulated speech signal and listening groups in either their perceptual accuracy or listening effort.Conclusion: Non-native listeners are not more strongly affected by spectrotemporal degradations than native listeners, and less proficient non-native listeners are not more strongly affected by these degradations than more proficient non-native listeners

Creating a common language for soundscape research:Translation and validation of Dutch soundscape attributes

Much of the work into the understanding of our auditory environment, referred to as soundscape research, has emerged from international and interdisciplinary research. This has enabled growth in understanding and increased opportunities for optimising shared environments but has also formed one major obstacle: a lack of a common language to describe soundscapes. Therefore, the purpose of this study is to validate translated soundscape descriptors in Dutch as part of the Soundscape Attributes Translation Project (SATP). For this, an expert panel of seven soundscape researchers from The Netherlands and Flanders (Belgium) translated the original eight English attributes into Dutch. Subsequently, following standardised materials and procedures, a sample of 32 Dutch participants completed a listening experiment in which they rated 27 audio files on the eight soundscape attributes. Results show modest evidence indicating that the Dutch translations were applied similarly to the original English attributes, with a slight (but not statistically significant) bias towards Pleasantness and Eventfulness in the Dutch sample. Bayesian analysis supports these findings by showing that the translations for the opposing attributes Uneventful and Annoying fit less well compared to the other attributes. Despite some limitations and while further research is necessary, our findings are promising and suggest that, although not perfect, the Dutch translations of the English soundscape attributes could already be useful for describing thegeneral appraisal of a person’s soundscape in The Netherlands