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Relationship between perceptual learning in speech and statistical learning in younger and older adults.

Neger TM, Rietveld T, Janse E - Front Hum Neurosci (2014)

Bottom Line: Younger and older adults showed similar amounts of perceptual learning, but only younger adults showed significant statistical learning.In younger adults, amount of adaptation was associated with lexical knowledge and with statistical learning ability.Results suggest that perceptual and statistical learning share mechanisms of implicit regularity detection, but that the ability to detect statistical regularities is impaired in older adults if visual sequences are presented quickly.

View Article: PubMed Central - PubMed

Affiliation: Centre for Language Studies, Radboud University Nijmegen Nijmegen, Netherlands ; International Max Planck Research School for Language Sciences Nijmegen, Netherlands.

ABSTRACT
Within a few sentences, listeners learn to understand severely degraded speech such as noise-vocoded speech. However, individuals vary in the amount of such perceptual learning and it is unclear what underlies these differences. The present study investigates whether perceptual learning in speech relates to statistical learning, as sensitivity to probabilistic information may aid identification of relevant cues in novel speech input. If statistical learning and perceptual learning (partly) draw on the same general mechanisms, then statistical learning in a non-auditory modality using non-linguistic sequences should predict adaptation to degraded speech. In the present study, 73 older adults (aged over 60 years) and 60 younger adults (aged between 18 and 30 years) performed a visual artificial grammar learning task and were presented with 60 meaningful noise-vocoded sentences in an auditory recall task. Within age groups, sentence recognition performance over exposure was analyzed as a function of statistical learning performance, and other variables that may predict learning (i.e., hearing, vocabulary, attention switching control, working memory, and processing speed). Younger and older adults showed similar amounts of perceptual learning, but only younger adults showed significant statistical learning. In older adults, improvement in understanding noise-vocoded speech was constrained by age. In younger adults, amount of adaptation was associated with lexical knowledge and with statistical learning ability. Thus, individual differences in general cognitive abilities explain listeners' variability in adapting to noise-vocoded speech. Results suggest that perceptual and statistical learning share mechanisms of implicit regularity detection, but that the ability to detect statistical regularities is impaired in older adults if visual sequences are presented quickly.

No MeSH data available.


Related in: MedlinePlus

Mean hearing threshold (in dB HL) at 0.25, 0.5, 1, 2, 4, and 8 kHz for both ears in younger (n = 59) and older adults (n = 73). Error bars indicate two standard error from the mean.
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Figure 1: Mean hearing threshold (in dB HL) at 0.25, 0.5, 1, 2, 4, and 8 kHz for both ears in younger (n = 59) and older adults (n = 73). Error bars indicate two standard error from the mean.

Mentions: Hearing thresholds. Age-related hearing loss is prevalent in older adults (Lin et al., 2011). Poorer hearing may affect perceptual learning as auditory input contains less detail, thereby interfering with accessing and retuning low-level representations. Participants' auditory function was assessed by measuring air-conduction pure tone thresholds with the aid of an Oscilla USB-300 screening audiometer. As age-related hearing loss particularly affects sensitivity to high frequencies, a high-frequency pure tone average [PTAH] was taken as index of hearing acuity. This PTAH was calculated as the mean hearing threshold over 1, 2, and 4 kHz (instead of the standard PTA over 0.5, 1, and 2 kHz). Only the PTAH of the best ear was entered in the analysis, as all auditory stimuli were presented binaurally. Twenty-seven older participants actually qualified for hearing aids on the basis of their hearing thresholds according to the standard of hearing-aid coverage in the Netherlands (PTAH of the worst ear ≥35 dB HL). None of the participants wore hearing aids in daily life, however. Higher thresholds reflected poorer hearing. Mean thresholds at different frequencies per age group are given in Figure 1.


Relationship between perceptual learning in speech and statistical learning in younger and older adults.

Neger TM, Rietveld T, Janse E - Front Hum Neurosci (2014)

Mean hearing threshold (in dB HL) at 0.25, 0.5, 1, 2, 4, and 8 kHz for both ears in younger (n = 59) and older adults (n = 73). Error bars indicate two standard error from the mean.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150448&req=5

Figure 1: Mean hearing threshold (in dB HL) at 0.25, 0.5, 1, 2, 4, and 8 kHz for both ears in younger (n = 59) and older adults (n = 73). Error bars indicate two standard error from the mean.
Mentions: Hearing thresholds. Age-related hearing loss is prevalent in older adults (Lin et al., 2011). Poorer hearing may affect perceptual learning as auditory input contains less detail, thereby interfering with accessing and retuning low-level representations. Participants' auditory function was assessed by measuring air-conduction pure tone thresholds with the aid of an Oscilla USB-300 screening audiometer. As age-related hearing loss particularly affects sensitivity to high frequencies, a high-frequency pure tone average [PTAH] was taken as index of hearing acuity. This PTAH was calculated as the mean hearing threshold over 1, 2, and 4 kHz (instead of the standard PTA over 0.5, 1, and 2 kHz). Only the PTAH of the best ear was entered in the analysis, as all auditory stimuli were presented binaurally. Twenty-seven older participants actually qualified for hearing aids on the basis of their hearing thresholds according to the standard of hearing-aid coverage in the Netherlands (PTAH of the worst ear ≥35 dB HL). None of the participants wore hearing aids in daily life, however. Higher thresholds reflected poorer hearing. Mean thresholds at different frequencies per age group are given in Figure 1.

Bottom Line: Younger and older adults showed similar amounts of perceptual learning, but only younger adults showed significant statistical learning.In younger adults, amount of adaptation was associated with lexical knowledge and with statistical learning ability.Results suggest that perceptual and statistical learning share mechanisms of implicit regularity detection, but that the ability to detect statistical regularities is impaired in older adults if visual sequences are presented quickly.

View Article: PubMed Central - PubMed

Affiliation: Centre for Language Studies, Radboud University Nijmegen Nijmegen, Netherlands ; International Max Planck Research School for Language Sciences Nijmegen, Netherlands.

ABSTRACT
Within a few sentences, listeners learn to understand severely degraded speech such as noise-vocoded speech. However, individuals vary in the amount of such perceptual learning and it is unclear what underlies these differences. The present study investigates whether perceptual learning in speech relates to statistical learning, as sensitivity to probabilistic information may aid identification of relevant cues in novel speech input. If statistical learning and perceptual learning (partly) draw on the same general mechanisms, then statistical learning in a non-auditory modality using non-linguistic sequences should predict adaptation to degraded speech. In the present study, 73 older adults (aged over 60 years) and 60 younger adults (aged between 18 and 30 years) performed a visual artificial grammar learning task and were presented with 60 meaningful noise-vocoded sentences in an auditory recall task. Within age groups, sentence recognition performance over exposure was analyzed as a function of statistical learning performance, and other variables that may predict learning (i.e., hearing, vocabulary, attention switching control, working memory, and processing speed). Younger and older adults showed similar amounts of perceptual learning, but only younger adults showed significant statistical learning. In older adults, improvement in understanding noise-vocoded speech was constrained by age. In younger adults, amount of adaptation was associated with lexical knowledge and with statistical learning ability. Thus, individual differences in general cognitive abilities explain listeners' variability in adapting to noise-vocoded speech. Results suggest that perceptual and statistical learning share mechanisms of implicit regularity detection, but that the ability to detect statistical regularities is impaired in older adults if visual sequences are presented quickly.

No MeSH data available.


Related in: MedlinePlus