When Often is Better Than Always: Variability in High Frequency Marker Words Helps Language Acquisition

Frost, R. L. . 1 , Monaghan, P. 1, 2 & Christiansen, M. H. . 3, 4

1 Lancaster University, UK
2 Max Planck Institute for Psycholinguistics, Nijmegen
3 Cornell University, USA
4 Aarhus University, Denmark

High-frequency words have been found to benefit speech segmentation (Bortfeld, Morgan, Golinkoff, & Rathbun, 2005) and grammatical categorisation (Monaghan, Christiansen, & Chater, 2007) - possibly simultaneously (Frost, Monaghan & Christiansen, 2016). Previous studies have tested the effect of high-frequency words on language acquisition by presenting them reliably within the experimental language, however natural language contains noise and variability that may provide further opportunities for robust learning (Monaghan, 2017). We tested the effect of variability on learning by familiarising adults with continuous speech comprising repetitions of target words, which were preceded by one of two high-frequency marker words 100%, 67%, or 33% of the time, with marker words distinguishing targets into two categories. Participants completed speech segmentation and categorisation tests, followed by a cross-situational word learning task where the same target words present in the continuous speech were mapped onto referents from two different grammatical categories. There was a clear advantage of variability: the 67% group performed best on measures of segmentation, categorisation, and learning the meaning of words in the cross-situational learning task. The data indicate that variability can help learners to use the same high-frequency words to inform both speech segmentation and grammatical categorisation.