An official website of the United States government
Abstract The current study utilized eye-tracking to investigate the effects of intersensory redundancy and language on infant visual attention and detection of a change in prosody in audiovisual speech. Twelve-month-old monolingual English-learning infants viewed either synchronous (redundant) or asynchronous (non-redundant) presentations of a woman speaking in native or non-native speech. Halfway through each trial, the speaker changed prosody from infant-directed speech (IDS) to adult-directed speech (ADS) or vice versa. Infants focused more on the mouth of the speaker on IDS trials compared to ADS trials regardless of language or intersensory redundancy. Additionally, infants demonstrated greater detection of prosody changes from IDS speech to ADS speech in native speech. Planned comparisons indicated that infants detected prosody changes across a broader range of conditions during redundant stimulus presentations. These findings shed light on the influence of language and prosody on infant attention and highlight the complexity of audiovisual speech processing in infancy.
more »
« less
Infant placement and language exposure in daily life
Abstract Children's daily contexts shape their experiences. In this study, we assessed whether variations in infant placement (e.g., held, bouncy seat) are associated with infants' exposure to adult speech. Using repeated survey sampling of mothers and continuous audio recordings, we tested whether the use of independence‐supporting placements was associated with adult speech exposure in a Southeastern U.S. sample of 60 4‐ to 6‐month‐old infants (38% male, predominately White, not Hispanic/Latinx, from higher socioeconomic status households). Within‐subject analyses indicated that independence‐supporting placements were associated with exposure to fewer adult words in the moment. Between‐subjects analyses indicated that infants more frequently reported to be in independence‐supporting placements that also provided posture support (i.e., an exersaucer) were exposed to relatively fewer adult words and less consistent adult speech across the day. These findings indicate that infants' opportunities for exposure to adult speech ‘in the wild’ may vary based on immediate physical context.
more »
« less
- Award ID(s):
- 2042285
- PAR ID:
- 10525891
- Publisher / Repository:
- Infant and Child Development
- Date Published:
- Journal Name:
- Infant and Child Development
- Volume:
- 32
- Issue:
- 3
- ISSN:
- 1522-7227
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Abstract Computational models of infant word‐finding typically operate over transcriptions of infant‐directed speech corpora. It is now possible to test models of word segmentation on speech materials, rather than transcriptions of speech. We propose that such modeling efforts be conducted over the speech of the experimental stimuli used in studies measuring infants' capacity for learning from spoken sentences. Correspondence with infant outcomes in such experiments is an appropriate benchmark for models of infants. We demonstrate such an analysis by applying the DP‐Parser model of Algayres and colleagues to auditory stimuli used in infant psycholinguistic experiments by Pelucchi and colleagues. The DP‐Parser model takes speech as input, and creates multiple overlapping embeddings from each utterance. Prospective words are identified as clusters of similar embedded segments. This allows segmentation of each utterance into possible words, using a dynamic programming method that maximizes the frequency of constituent segments. We show that DP‐Parse mimics American English learners' performance in extracting words from Italian sentences, favoring the segmentation of words with high syllabic transitional probability. This kind of computational analysis over actual stimuli from infant experiments may be helpful in tuning future models to match human performance.more » « less
-
We asked whether increased exposure to iambs, two-syllable words with stress on the second syllable (e.g., guitar), by way of another language – Spanish – facilitates English learning infants' segmentation of iambs. Spanish has twice as many iambic words (40%) compared to English (20%). Using the Headturn Preference Procedure we tested bilingual Spanish and English learning 8-month-olds' ability to segment English iambs. Monolingual English learning infants succeed at this task only by 11 months. We showed that at 8 months, bilingual Spanish and English learning infants successfully segmented English iambs, and not simply the stressed syllable, unlike their monolingual English learning peers. At the same age, bilingual infants failed to segment Spanish iambs, just like their monolingual Spanish peers. These results cannot be explained by bilingual infants' reliance on transitional probability cues to segment words in both their native languages because statistical cues were comparable in the two languages. Instead, based on their accelerated development, we argue for autonomous but interdependent development of the two languages of bilingual infants.more » « less
-
Abstract The production of speech and gesture is exquisitely temporally coordinated. In autistic individuals, speech-gesture synchrony during spontaneous discourse is disrupted. To evaluate whether this asynchrony reflects motor coordination versus language production processes, the current study examineddeliberatelyperformed hand movements during speech in youth with autism spectrum disorder (ASD) compared to neurotypical youth. Neurotypical adult performance provided a mature baseline. Participants read aloud rhythmic nursery rhymes, while producing a beat-like hand movement. An automated pixel-change video measure identified kinematic peaks; using smoothed acoustic envelope analyses, we identified peaks in speech. Results indicated few diagnostic group differences in explicit speech-movement coordination, although adolescent performance differed from adults. Adults demonstrated higher tempo and greater rhythmicity in their coordination; this group difference suggests that the method is sufficiently subtle to reveal individual differences and that this form of complex coordination undergoes ongoing maturation beyond adolescence. The sample is small, and thus results are necessarily preliminary. In the context of prior speech-gesture coordination studies, these findings of intact synchrony are consistent with the hypothesis that it is the demands of discourse planning, rather than motor coordination, that have led to prior findings of asynchrony during spontaneous speech; this possibility awaits future research.more » « less
-
Abstract What makes a word easy to learn? Early‐learned words are frequent and tend to name concrete referents. But words typically do not occur in isolation. Some words are predictable from their contexts; others are less so. Here, we investigate whether predictability relates to when children start producing different words (age of acquisition; AoA). We operationalized predictability in terms of a word's surprisal in child‐directed speech, computed using n‐gram and long‐short‐term‐memory (LSTM) language models. Predictability derived from LSTMs was generally a better predictor than predictability derived from n‐gram models. Across five languages, average surprisal was positively correlated with the AoA of predicates and function words but not nouns. Controlling for concreteness and word frequency, more predictable predicates and function words were learned earlier. Differences in predictability between languages were associated with cross‐linguistic differences in AoA: the same word (when it was a predicate) was produced earlier in languages where the word was more predictable.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/icd.2405
