We are a public research laboratory in Paris specializing in the psychophysics, experimental and developmental psychology of perception, action, and language. Please click on the links to the left to learn more about our research and teaching.
Here is our report.

Our director is Andrei Gorea
and our associate director is Thierry Nazzi

Event Information:

  • Mon

    Iris-Corinna Schwarz, Stockholm University

    11hSalle de réunion du LPP, H432, 4ème étage, Centre Biomédical des Saints Pères 45 rue des Sts Pères, 75006 Paris

    Aspects of speech input in parent-child interaction and their relationship to child language development: A snapshot of ongoing research at Stockholm Babylab


    Child language development is speech-input dependent, making parent-child interaction one of the main vessels promoting language development. At Stockholm Babylab, a large proportion of the research that I’m part of is focused on speech input in the nucleus of the parent-child dyad. This parental speech input is studied on different levels.

    First, on a macro-level, it is the amount of speech input that correlates with language outcome (e.g., Weisleder & Fernald, 2013). At Stockholm Babylab, we are currently evaluating the LENA system when it is used on Swedish (Schwarz et al., under review), paving the way for large-scale studies and interventions based on LENA estimates. The LENA system has the potential to open up the methodological bottleneck of transcribing or annotating recordings, as it uses automatic segmentation of the audio signal based on its acoustic properties. Further, recent results from our team indicate that amount of speech input is directly related to maturation of speech sound categories early in infancy (Marklund, Schwarz, & Lacerda, submitted), suggesting that the amount of speech input is important for language development on a fine-grained level long before the child herself starts to talk.

    Second, contingency of parental responsiveness in parent-child interaction that is also related to language development (e.g., Goldstein & Schwade, 2008). The Stockholm Babylab team has shown that parents of 18-month-old children have different response times depending on the vocabulary size of the child (Marklund, Marklund, Lacerda & Schwarz, 2015). Parents of children with large vocabularies respond faster to their children’s utterances than do parents of children with smaller vocabularies. While not implying causation, this study still highlights that temporal aspects of parent-child interaction are important to study with respect to the impact they may have on language development. This counts also for the timing of infant responses to parent speech input. An ongoing study at Stockholm Babylab on temporal aspects of parent-child interaction gives a first indication for the possibility that 6-month-olds’ response time to parent target utterances is dependent on whether the parent is the primary or secondary caregiver, implying differences in the amount of speech exposure created by the two parents (Schwarz et al., to be submitted). Note that this is work in progress, and that these results are only preliminary.

    Third, on a micro-level, we study affect in parents’ infant-directed speech and its relation to vocabulary development in a collaboration with The MARCS Institute at Western Sydney University in two ongoing studies; one that describes the perceived affective intent of Swedish infant-directed speech and compares it to previous results on Australian English (Kitamura & Burnham, 2003), and one that investigates the acoustic correlates of perceived affect. Other micro-level characteristics of parent input as for example repetitions are studied in the ongoing MINT-project, which I will present in an overview.



    Goldstein, M. H., & Schwade, J. A. (2008). Social feedback to infants' babbling facilitates rapid phonological learning.

    Psychological Science, 19(5), 515-523. doi: 10.1111/j.1467-9280.2008.02117.x

    Kitamura, C., & Burnham, D. (2003). Pitch and communicative intent in mother's speech: adjustments for age and sex in

    the first year. Infancy, 4(1), 85-110.

    Marklund, E., Schwarz, I.-C., & Lacerda, F. (submitted). Amount of speech exposure predicts vowel categorization in 4- and

    8-month-olds. Developmental Cognitive Neuroscience.

    Marklund, U., Marklund, E., Lacerda, F., & Schwarz, I.-C. (2015). Pause and utterance duration in child-directed speech in

    relation to child vocabulary size. Journal of Child Language, 42(5), 1158-1171. doi: 10.1017/S0305000914000609

    Schwarz, I.-C., Botros, N., Lord, A., Marcusson, A., Tidelius, H. & Marklund, E. (under review). The LENATM system applied to

    Swedish: Reliability of the Adult Word Count estimate. Paper to be presented at Interspeech 2017, Stockholm, Sweden.

    Schwarz, I.-C., Ekman, M., Hällström, E., Moretta, M.R., Myr, J. & Marklund, U. (to be submitted). 6-month-olds respond

    faster to target utterances from primary caregivers than to secondary caregivers. Paper to be presented at the

    Workshop Many Paths to Language Acquisition 2017, Nijmegen, Netherlands.

    Weisleder, A., & Fernald, A. (2013). Talking to children matters - Early language experience strengthens processing and

    builds vocabulary. Psychological Science, 24(11), 2134-2152. doi: 10.1177/0956797613488145



    Invited by the Speech team

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