Word recognition and phonological representation in very low birth weight preterms

Several studies have shown impaired neurocognitive development in infants born very preterm. Language is one of the areas that may be affected. Early lexical development measurements have revealed possible delays associated with low gestational age, but no studies have analyzed lexical processing using real-time measures in this at-risk population.

To explore the effects of preterm birth on the robustness of phonological representations and lexical processing speed.

Eighteen two-year-old VLBW healthy preterms (≤32weeks of gestation; ≤1500g) and a matched group of at term infants, equivalent in age, gender, SES, linguistic environment and expressive lexicon were compared in a 'looking-while-listening' task, using correctly pronounced and mispronounced known words involving a vowel change. Percentage of target fixation, longest look duration, shift rate and orientation latency measures were used to analyze possible between-group differences in phonological representation and familiar word recognition processes.

Based on the percentage of fixation time measure both groups succeeded at word recognition and responded similarly to mispronunciations. However, preterms significantly differed from full-terms in processing speed measures, showing longer look duration, lower shift rate and slower orientation latencies to target from distracter.

Preterm birth negatively affects lexical processing speed. Birth weight and gestational age are two critical variables in these results. Slower language processing in preterms can compromise the acquisition of more complex lexical and grammatical representations later in development and may underlie poor language outcomes frequently observed in children born very prematurely.