Proceedings of the Annual Meeting of the Cognitive Science Society

It has been proposed that language evolves under the joint con-straints of communicative expressivity and cognitive ease. Weexplore this idea in the historical emergence of word forms.We hypothesize that new word forms that enter the lexiconshould reflect a trade-off between predictability and distinc-tiveness. An emergent word form can be highly predictable ifit efficiently reuses elements from the existing word forms, re-sulting in low cognitive load. An emergent word form shouldalso be sufficiently distinctive from the existing lexicon, facil-itating communicative expressivity. We test our hypothesis byexamining the properties of 34,478 emergent word forms overthe past 200 years of Modern English. We show how wordforms at future time t + 1 are bounded statistically betweenn-gram generated word forms (highly predictable) and slangwords that are outside the standard lexicon (highly distinctive)at time t. Our work supports the view of cognitive economy inlexical emergence.