Dataset Information

Distinct neural encoding of glimpsed and masked speech in multitalker situations.

ABSTRACT: Humans can easily tune in to one talker in a multitalker environment while still picking up bits of background speech; however, it remains unclear how we perceive speech that is masked and to what degree non-target speech is processed. Some models suggest that perception can be achieved through glimpses, which are spectrotemporal regions where a talker has more energy than the background. Other models, however, require the recovery of the masked regions. To clarify this issue, we directly recorded from primary and non-primary auditory cortex (AC) in neurosurgical patients as they attended to one talker in multitalker speech and trained temporal response function models to predict high-gamma neural activity from glimpsed and masked stimulus features. We found that glimpsed speech is encoded at the level of phonetic features for target and non-target talkers, with enhanced encoding of target speech in non-primary AC. In contrast, encoding of masked phonetic features was found only for the target, with a greater response latency and distinct anatomical organization compared to glimpsed phonetic features. These findings suggest separate mechanisms for encoding glimpsed and masked speech and provide neural evidence for the glimpsing model of speech perception.

SUBMITTER: Raghavan VS

PROVIDER: S-EPMC10243639 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Distinct neural encoding of glimpsed and masked speech in multitalker situations.

Raghavan Vinay S VS O'Sullivan James J Bickel Stephan S Mehta Ashesh D AD Mesgarani Nima N

PLoS biology 20230606 6

Humans can easily tune in to one talker in a multitalker environment while still picking up bits of background speech; however, it remains unclear how we perceive speech that is masked and to what degree non-target speech is processed. Some models suggest that perception can be achieved through glimpses, which are spectrotemporal regions where a talker has more energy than the background. Other models, however, require the recovery of the masked regions. To clarify this issue, we directly record ...[more]

PMID: 37279203

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Dataset Information

Distinct neural encoding of glimpsed and masked speech in multitalker situations.

Publications

Distinct neural encoding of glimpsed and masked speech in multitalker situations.

Similar Datasets

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