Wolfe, JeremyAlvarez, GeorgeSherman, Ashley M.Rosenholtz, RuthKuzmova, Yoana I.kuzmova, yoana2019-09-102011-06-14Wolfe, Jeremy, M. Alvarez, George Rosenholtz, A. Kuzmova, and Ruth Sherman. "Visual Search for Arbitrary Objects in Real Scenes." Attention, Perception, & Psychophysics 73, no. 6 (2011): 1650-671.1943-39211943-393Xhttp://nrs.harvard.edu/urn-3:HUL.InstRepos:41302437How efficient is visual search in real scenes? In searches for targets among arrays of randomly placed distractors, efficiency is often indexed by the slope of the reaction time (RT) × Set Size function. However, it may be impossible to define set size for real scenes. As an approximation, we hand-labeled 100 indoor scenes and used the number of labeled regions as a surrogate for set size. In Experiment 1, observers searched for named objects (a chair, bowl, etc.). With set size defined as the number of labeled regions, search was very efficient (~5 ms/item). When we controlled for a possible guessing strategy in Experiment 2, slopes increased somewhat (~15 ms/ item), but they were much shallower than search for a random object among other distinctive objects outside of a scene setting (Exp. 3: ~40 ms/item). In Experiments 4–6, observers searched repeatedly through the same scene for different objects. Increased familiarity with scenes had modest effects on RTs, while repetition of target items had large effects (>500 ms). We propose that visual search in scenes is efficient because scene-specific forms of attentional guidance can eliminate most regions from the “functional set size” of items that could possibly be the target.en-USLinguistics and LanguageExperimental and Cognitive PsychologySensory SystemsLanguage and LinguisticsJournal Article2019-09-1010.3758/s13414-011-0153-3