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- Kushnerenko, Elena, et al.
(författare)
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Brain responses to audiovisual speech mismatch in infants are associated with individual differences in looking behaviour
- 2013
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Ingår i: European Journal of Neuroscience. - : Wiley. - 0953-816X .- 1460-9568.
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Tidskriftsartikel (refereegranskat)abstract
- Research on audiovisual speech integration has reported high levels of individual variability, especially among young infants. In the present study we tested the hypothesis that this variability results from individual differences in the maturation of audiovisual speech processing during infancy. A developmental shift in selective attention to audiovisual speech has been demonstrated between 6 and 9 months with an increase in the time spent looking to articulating mouths as compared to eyes (Lewkowicz & Hansen-Tift. (2012) Proc. Natl Acad. Sci. USA, 109, 1431-1436; Tomalski et al. (2012) Eur. J. Dev. Psychol., 1-14). In the present study we tested whether these changes in behavioural maturational level are associated with differences in brain responses to audiovisual speech across this age range. We measured high-density event-related potentials (ERPs) in response to videos of audiovisually matching and mismatched syllables /ba/ and /ga/, and subsequently examined visual scanning of the same stimuli with eye-tracking. There were no clear age-specific changes in ERPs, but the amplitude of audiovisual mismatch response (AVMMR) to the combination of visual /ba/ and auditory /ga/ was strongly negatively associated with looking time to the mouth in the same condition. These results have significant implications for our understanding of individual differences in neural signatures of audiovisual speech processing in infants, suggesting that they are not strictly related to chronological age but instead associated with the maturation of looking behaviour, and develop at individual rates in the second half of the first year of life.
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| 2. |
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| 3. |
- Tomalski, Przemyslaw, et al.
(författare)
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Socioeconomic status and functional brain development - associations in early infancy
- 2013
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Ingår i: Developmental Science. - : Wiley. - 1363-755X .- 1467-7687. ; 16, s. 676-687
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Tidskriftsartikel (refereegranskat)abstract
- Socioeconomic status (SES) impacts on both structural and functional brain development in childhood, but how early its effects can be demonstrated is unknown. In this study we measured resting baseline EEG activity in the gamma frequency range in awake 6-9-month-olds from areas of East London with high socioeconomic deprivation. Between-subjects comparisons of infants from low- and high-income families revealed significantly lower frontal gamma power in infants from low-income homes homes. Similar power differences were found when comparing infants according to maternal occupation, with lower occupational status groups yielding lower power. Infant sleep, maternal education, length of gestation, and birth weight, as well as smoke exposure and bilingualism, did not explain these differences. Our results show that the effects of socioeconomic disparities on brain activity can already be detected in early infancy, potentially pointing to very early for language and attention difficulties. This is the first study to reveal region-selective differences in functional brain development associated with early infancy in low-income families.
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