Communicative skills in children with specific language impairments: a comparison with their language-matched siblings

Using Predictability for Lexical Segmentation

This study investigates a strategy based on predictability of consecutive sub-lexical units in learning to segment a continuous speech stream into lexical units using computational modeling and simulations. Lexical segmentation is one of the early challenges during language acquisition, and it has been studied extensively through psycholinguistic experiments as well as computational methods. However, despite strong empirical evidence, the explicit use of predictability of basic sub-lexical units in models of segmentation is underexplored. This paper presents an incremental computational model of lexical segmentation for exploring the usefulness of predictability for lexical segmentation. We show that the predictability cue is a strong cue for segmentation. Contrary to earlier reports in the literature, the strategy yields state-of-the-art segmentation performance with an incremental computational model that uses only this particular cue in a cognitively plausible setting. The paper also reports an in-depth analysis of the model, investigating the conditions affecting the usefulness of the strategy.

Practitioner review: the assessment of language pragmatics

BACKGROUND

The assessment of pragmatics expressed in spoken language is a central issue in the evaluation of children with communication impairments and related disorders. A developmental approach to assessment has remained problematic due to the complex interaction of social, linguistic, cognitive and cultural influences on pragmatics.

METHOD

A selective review and critique of current formal and informal testing methods and pragmatic analytic procedures.

RESULTS

Formal testing of pragmatics has limited potential to reveal the typical pragmatic abnormalities in interaction but has a significant role to play in the assessment of comprehension of pragmatic intent. Clinical assessment of pragmatics with the pre-school child should focus on elicitation of communicative intent via naturalistic methods as part of an overall assessment of social communication skills. Assessments for older children should include a comprehensive investigation of speech acts, conversational and narrative abilities, the understanding of implicature and intent as well as the child's ability to employ contextual cues to understanding. Practical recommendations are made regarding the choice of a core set of pragmatic assessments and elicitation techniques. The practitioner's attention is drawn to the lack of the usual safeguards of reliability and validity that have persisted in some language pragmatics assessments.

CONCLUSIONS

A core set of pragmatic assessment tools can be identified from the proliferation of instruments in current use. Further research is required to establish clearer norms and ranges in the development of pragmatic ability, particularly with respect to the understanding of inference, topic management and coherence.