Rastle, K. 1 & Davis, M. H. 2
1 Department of Psychology, Royal Holloway, University of London, UK
2 MRC Cognition and Brain Sciences Unit, Cambridge, UK
The generalisation of morphological knowledge is at the core of our language abilities. Our experience with a limited set of morphologically-complex words (e.g. unscrew) allows us to abstract knowledge about the components of those words (e.g. un-) that is critical for the interpretation and creation of new words (e.g. untweet). This research examined the role of consolidation in the acquisition of this morphological knowledge using an artificial language paradigm in which undergraduate participants were trained on novel suffixes (e.g. -nept) presented in novel word contexts (e.g. sleepnept). Participants were tested immediately after training or two days after training on a variety of tasks including a speeded auditory repetition test that assessed performance on trained items as well as items comprising an untrained suffix, an untrained stem or both (e.g. sleepnept vs. sleepnule, or sailnept vs. sailnule). Results of the auditory repetition task showed an advantage for trained items immediately after training, as these were repeated significantly faster than items with trained stems but untrained suffixes. Critically, this advantage generalised to untrained items comprising the novel suffixes (e.g. sailnept) but only in the group of participants tested two days after training. This study demonstrates that participants can acquire morphological representations in a laboratory context that are sufficiently robust to generalise to the interpretation of novel exemplars. It also suggests that this process of linguistic generalisation may require a period of overnight consolidation consistent with complementary systems theories of lexical learning.