Better offline retention of phonological sequences in children compared to adults

Smalle, Eleonore [UCL] Bogaerts, Louisa [Ghent University] Duyck, Wouter [Ghent University] Page, Mike [University of Hertfordshire] Edwards, Martin [UCL] Szmalec, Arnaud [UCL]

In a recent study on specific language impairment, Bishop et al. (2012) reported better offline retention of newly learned word-forms in children compared to adults. This accidental observation is consistent with the less-is-more hypothesis, which states that children are better language learners compared to adults, possibly because they have less memory resources available. The current study aimed to directly address the less-is-more hypothesis by using the Hebb repetition paradigm, in which sequences of phonemes are presented for immediate serial recall with one of the sequences repeated on every nth trial. Hebb learning occurs when recall for the repeated (Hebb) sequence increases across trials compared to the unrepeated filler sequences. We presented auditory sequences of 9 syllables (i.e. supraspan level) for immediate recall to a group of children (8-9 years old) and adults. Two Hebb sequences were repeated every 3th trial and re-presented after a short (4 hours) and long (one week) delay. We found that although children started learning more slowly than adults they catched up, and got even slightly better than the adults at the end of the week. More importantly, we found that adults were more sensitive to forgetting after both the short and long delay. The findings are discussed in the light of sensitive periods for language acquisition.