What have we learned from 15 years of research on cross-situational word learning? A focused review

Cross-Situational Statistical Word Learning in Late Language Emergence: An Online Study

PURPOSE

Cross-situational statistical learning is one mechanism by which typically developing toddlers map words to referents. Yet, this type of statistical learning has been found less efficient in children with developmental language disorder (DLD). The purpose of this article is to evaluate cross-situational statistical learning in very young children with language delay, late talkers (LTs), compared to typically talking toddlers. We predict that LTs will show inefficiency in cross-situational statistical word learning similar to older children with DLD.

METHOD

LT (n = 15, 18-34 months) and typical talker (TT; n = 15, 18-35 months) groups matched on chronological age and sex completed a cross-situational statistical learning task in which they were trained on six novel word-referent pairs and then tested on these word-referent associations. The experiment was completed on the participant's home computer, and gaze was recorded for the duration of the experiment. Mixed-effects models were used to evaluate group differences in time spent looking at labeled referents as a measure of learning.

RESULTS

The LT group spent an equal proportion of time looking at the named targets and the unnamed distractors when tested, suggesting minimal learning had occurred. The TT group, in contrast, spent a significantly greater proportion of time looking at the targets when labeled, indicating more established word-referent links.

CONCLUSIONS

These findings suggest that LTs, like older children with DLD, are less efficient at leveraging cross-situational statistical learning opportunities that may, in addition to other factors, contribute to their slow expressive vocabulary development.

Vocabulary interventions for children with developmental language disorder: a systematic review

Introduction

Developmental language disorder (DLD) is a neurodevelopmental condition often characterised by vocabulary difficulties that lead to academic and social challenges. The acquisition of vocabulary is a complex, dynamic process of mapping word sound (phonology) to meaning (semantics) supported by contextual cues; a complexity that vocabulary interventions need to address. To understand the key features and impact of such interventions, a systematic review of word-learning studies involving children aged 5-11 with DLD was conducted.

Method

A structured search covered seven electronic databases for the period 1990-2023. In addition, the reference lists of identified studies were searched manually. Studies were appraised for quality and data was extracted relating to word-learning effectiveness and intervention characteristics. Findings were reported as written summaries and quantitative data ranges.

Results

Sixteen relevant studies were identified with most appraised as medium quality. Interventions tended to be delivered individually in school by speech and language therapists. The most common outcome measure was expressive target-word tests, such as picture naming and word definitions. Interventions explicitly targeting phonological and semantic word features had the most high-quality studies reporting significant vocabulary gain. The inclusion of stories to provide context implicitly during phonological and semantic interventions was beneficial, though stories alone were less effective. Specificity in learning was noted across studies. Gains did not generally transfer to non-targeted words and showed depreciation following therapy. Intervention responses were influenced by children's language profiles. For example, children with more severe language difficulties were less responsive to contextual cues during story reading and were more distracted by extraneous music during multimedia-supported word learning.

Discussion

Whilst the available studies have limitations in range and quality, they do suggest some benefits of combining explicit and implicit vocabulary strategies and considering children's presenting profiles. Implications for practitioners supporting the individual needs of children with DLD are discussed. This includes addressing issues with the generalization and maintenance of vocabulary gains by targeting the most relevant words and encouraging recall and self-management strategies. Further research should explore the influence of home-school carryover.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022327345, PROSPERO, Reg: CRD42022327345.

Statistical learning ability at 17 months relates to early reading skills via oral language

Statistical learning ability has been found to relate to children's reading skills. Yet, statistical learning is also known to be vital for developing oral language skills, and oral language and reading skills relate strongly. These connections raise the question of whether statistical learning ability affects reading via oral language or directly. Statistical learning is multifaceted, and so different aspects of statistical learning might influence oral language and reading skills distinctly. In a longitudinal study, we determined how two aspects of statistical learning from an artificial language tested on 70 17-month-old infants-segmenting sequences from speech and generalizing the sequence structure-related to oral language skills measured at 54 months and reading skills measured at approximately 75 months. Statistical learning segmentation did not relate significantly to oral language or reading, whereas statistical learning generalization related to oral language, but only indirectly related to reading. Our results showed that children's early statistical learning ability was associated with learning to read via the children's oral language skills.

The Role of Feedback in the Statistical Learning of Language-Like Regularities

In language learning, learners engage with their environment, incorporating cues from different sources. However, in lab-based experiments, using artificial languages, many of the cues and features that are part of real-world language learning are stripped away. In three experiments, we investigated the role of positive, negative, and mixed feedback on the gradual learning of language-like statistical regularities within an active guessing game paradigm. In Experiment 1, participants received deterministic feedback (100%), whereas probabilistic feedback (i.e., 75% or 50%) was introduced in Experiment 2. Finally, Experiment 3 explored the impact of mixed probabilistic feedback (33% positive, 33% negative, 33% no feedback). The results showed that cross-situational learning of words was observed without feedback, but participants were able to learn structural regularities of the miniature language only when feedback was provided. Interestingly, the presence of positive feedback was particularly helpful for the learner, promoting more in-depth learning of the artificial language.