Increasing frequency leads to semantic specialization through the suspicious coincidence effect in statistical learning of constructions

Harmon, Z. & Kapatsinski, V.

University of Oregon

We exposed adult native English speakers to a miniature artificial language that contained four suffixes, -dan (plural), -nem (diminutive), -sil (plural non-diminutive) and -shoon (singular diminutive). Speakers of the language varied in how specific their referring expressions were. Thus either -dan (plural), -nem (diminutive) or -dannem could be used with plural diminutive meanings, while -sil and -shoon were in competition with the more general -dan and -nem. After training and testing participants on the full system, we boosted frequencies of some suffix-meaning pairings in a second training stage to see how learners restructure the system as a result of increased exposure to a certain mapping. In particular, increasing use of a form to express a meaning (e.g. -nem for singular diminutive) reduced its use to express related meanings (in this case, singular diminutive, where it lost to -shoon). These results suggest that increased use of a form with a certain meaning leads the form to specialize in expressing that meaning (a suspicious coincidence effect, Xu & Tenenbaum 2007). We discuss the implications of our finding for language change and specifically for the idea, proposed in usage-based grammaticalization theory, that increasing frequency alone leads to semantic bleaching / generalization (Bybee 2003).