Dataset Information

Gradient activation of speech categories facilitates listeners' recovery from lexical garden paths, but not perception of speech-in-noise.

ABSTRACT: Listeners activate speech-sound categories in a gradient way, and this information is maintained and affects activation of items at higher levels of processing (McMurray et al., 2002; Toscano et al., 2010). Recent findings by Kapnoula et al. (2017) suggest that the degree to which listeners maintain within-category information varies across individuals. Here we assessed the consequences of this gradiency for speech perception. To test this, we collected a measure of gradiency for different listeners using the visual analogue scaling (VAS) task used by Kapnoula et al. (2017). We also collected 2 independent measures of performance in speech perception: a visual world paradigm (VWP) task measuring participants' ability to recover from lexical garden paths (McMurray et al., 2009) and a speech-perception task measuring participants' perception of isolated words in noise. Our results show that categorization gradiency does not predict participants' performance in the speech-in-noise task. However, higher gradiency predicted higher likelihood of recovery from temporarily misleading information presented in the VWP task. These results suggest that gradient activation of speech sound categories is helpful when listeners need to reconsider their initial interpretation of the input, making them more efficient in recovering from errors. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

SUBMITTER: Kapnoula EC

PROVIDER: S-EPMC9069052 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Gradient activation of speech categories facilitates listeners' recovery from lexical garden paths, but not perception of speech-in-noise.

Kapnoula Efthymia C EC Edwards Jan J McMurray Bob B

Journal of experimental psychology. Human perception and performance 20210401 4

Listeners activate speech-sound categories in a gradient way, and this information is maintained and affects activation of items at higher levels of processing (McMurray et al., 2002; Toscano et al., 2010). Recent findings by Kapnoula et al. (2017) suggest that the degree to which listeners maintain within-category information varies across individuals. Here we assessed the consequences of this gradiency for speech perception. To test this, we collected a measure of gradiency for different liste ...[more]

PMID: 33983791

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Project description:When listening to degraded speech, such as speech delivered by a cochlear implant (CI), listeners make use of top-down linguistic knowledge to facilitate speech recognition. Lexical knowledge supports speech recognition and enhances the perceived clarity of speech. Yet, the extent to which lexical knowledge can be used to effectively compensate for degraded input may depend on the degree of degradation and the listener's age. The current study investigated lexical effects in the compensation for speech that was degraded via noise-vocoding in younger and older listeners. In an online experiment, younger and older normal-hearing (NH) listeners rated the clarity of noise-vocoded sentences on a scale from 1 ("very unclear") to 7 ("completely clear"). Lexical information was provided by matching text primes and the lexical content of the target utterance. Half of the sentences were preceded by a matching text prime, while half were preceded by a non-matching prime. Each sentence also consisted of three key words of high or low lexical frequency and neighborhood density. Sentences were processed to simulate CI hearing, using an eight-channel noise vocoder with varying filter slopes. Results showed that lexical information impacted the perceived clarity of noise-vocoded speech. Noise-vocoded speech was perceived as clearer when preceded by a matching prime, and when sentences included key words with high lexical frequency and low neighborhood density. However, the strength of the lexical effects depended on the level of degradation. Matching text primes had a greater impact for speech with poorer spectral resolution, but lexical content had a smaller impact for speech with poorer spectral resolution. Finally, lexical information appeared to benefit both younger and older listeners. Findings demonstrate that lexical knowledge can be employed by younger and older listeners in cognitive compensation during the processing of noise-vocoded speech. However, lexical content may not be as reliable when the signal is highly degraded. Clinical implications are that for adult CI users, lexical knowledge might be used to compensate for the degraded speech signal, regardless of age, but some CI users may be hindered by a relatively poor signal.

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Dataset Information

Gradient activation of speech categories facilitates listeners' recovery from lexical garden paths, but not perception of speech-in-noise.

Publications

Gradient activation of speech categories facilitates listeners' recovery from lexical garden paths, but not perception of speech-in-noise.

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