Proceedings of the Annual Meeting of the Cognitive Science Society

This paper presents a new methodology for examining the phenomenon of subitizing. Subjects were presented with a standard numerosity-detection task but for a range of presentation times to allow Task-Accuracy Functions to be computed for individual subjects. The data appear to show a continuous change in processing for numerosities from 2 to 5 when the data are aggregated across subjects. At the level of individual subjects, there appear to be qualitative shifts in enumeration processing after 3 or 4 objects. The approach used in Uiis experiment m a y be used to test the claim that subitizing is a distinct enumeration process that can be used for small numbers of objects.