Visual Search in Scenes
How do I find my lost keys? Visual search for real objects in real scenes does not always follow the same laws as visual search displays that are frequently used in experiments. In particular, the number of objects in a scene has very little influence over the difficulty of the search. In seeking to understand why this is the case, my colleagues and I have put forth a two pathway theory whereby a non-selective and global analysis of the scene can allow for activations of possible object locations while a selective process can evaluate each location in a serial manner (Wolfe et al, TiCS 2011).
What sort of information makes up the global image analysis? My global scene properties seemed like a good place to start. We examined visual search slopes for scenes with a particular global property, such as highly navigable scenes among non-navigable distractors. It does not appear that global properties are available without selective attention as search times increased substantially with increasing numbers of distractors (Greene & Wolfe, JoV 2011).