The path to polarity sensitivity: Acquisition of either and too

Abstract

This talk presents an experimental investigation of how children acquire the contrasting licensing requirements of the negative polarity item (NPI) "either" and its positive polarity item (PPI) counterpart "too". We observe that i) children aged 3-5 display stable, non-categorical preferences in the direction of the adult grammar, and ii) at age 6, children exhibit a categorical, adult-like understanding of the licensing conditions of “either” but not of “too”. This adds to a growing body of results suggesting that NPIs are easier to acquire than PPIs and raises questions about how to characterize the learning mechanism that produces the observed developmental pattern.