Proceedings of the Annual Meeting of the Cognitive Science Society

Hurford (1975) proposed that number words across languages follow a set of phrase-structure rules (syntax), together with a constraint known as the packing strategy. The present study taught participants a novel numeral system to test whether people's mental representations of number words align with this framework. We tested speakers of English and Turkish, which contain irregularities relative to the syntax, and Chinese, which aligns closely with it. Participants' task was to generate large numbers (e.g., 27) in a base-3 artificial number system. In the training conditions, participants learned expressions consistent with both syntax and the packing strategy at different magnitudes (larger vs. smaller numbers); the baseline condition received no training. Across conditions, Chinese speakers were more likely than English or Turkish speakers to produce number words consistent with Hurford's proposal. This advantage was due to greater sensitivity to syntax, not packing. Across languages, training increased sensitivity to syntax relative to baseline, whereas sensitivity to packing did not differ between conditions. Together, these findings suggest that people represent the structure of number words through two distinct cognitive processes rather than through a single unified system.