My talk for the Sydney University psychology department will be at 4pm in the Education building, room 424. Below, the abstract:
Localizing a single object relative to oneself is fairly easy—ever seen a plant reaching towards the sun? It’s a no-brainer. A less trivial task is determining the position of two objects relative to each other. Humans evolved brains that can do it, probably because it’s important for survival, but we don’t know how we do it. I asked some people to look at a stable scene and report which objects are adjacent. They said, “the red disc is next to the green disc” or “the red disc is next to the yellow disc”. Performance was essentially perfect. When the display started spinning, however, queer things started happening. These things suggest that apprehending the spatial relationship among objects requires a shift of attention from one object to the other. They also suggest that to perceive the spatial relationships among moving objects, the ability to follow an object with attention is critical. The ability to follow an object with attention was tested by many previous investigators, who found that people can keep track of about four objects at once. But previous investigators never moved their objects as fast as we move ours. Our findings with speedy objects dispel previous theories of tracking and suggest that the faster an object moves, the more attentional resource it consumes. Until nothing is left.
1. Holcombe, A., Linares, D., & Vaziri-Pashkam, M. (2011). Perceiving Spatial Relations via Attentional Tracking and Shifting. Current Biology, 21, 1-5. DOI: 10.1016/j.cub.2011.05.031
2. Holcombe, A.O., Chen, W.Y. (2011, submitted). Tracking a single fast-moving object exhausts attentional resources. (See the associated poster)
[Updated post with the time (4pm). Thanks Mat!]