Haladjian, Pylyshyn, & Gallistel (2009). Enumerating by location increases the subitizing limit. Poster presented at the 17th Annual Object Perception, Attention, and Memory (OPAM) Meeting of the Psychonomic Society, Boston, MA (11/09).
This study investigates the enumeration of small sets of objects using a novel subitizing task. Observers viewed brief displays (50 or 200 ms) of 2-9 small black discs on a gray background. Numerosity and location information were obtained by requiring observers to mark the perceived locations of the discs, which allowed for a nonverbal report of numerosity. In the location-marking condition, observers accurately reported higher numerosities (6 items) than in the control condition (4 items) where numerosity was reported conventionally. Additionally, location accuracy benefited from increased display durations. These results give new insights to subitizing, spatial perception, and numerical cognition.