When Cuing V isual Search, Sometimes M ore Is Less .

1. When Cuing Visual Search, Sometimes More Is Less. & Richard A. Abrams William H. Knapp III Washington Universityin St. Louis Istanbul Şehir University Other Results Abstract More Methods Typically in guided visual search tasks, the more information a cue provides about the target of one’s search, the better participants perform. Although our participants showed the typical pattern when searching for targets identified by picture cues, we found the opposite results with verbal cues. With increasing SOAs, response times converged with pictures and words only for target present trials. Independent Variables Cue Type: Word or Picture. F(2,44)=8.4, p<.05, η2=0.17 Cue Informativeness: More or Less. SOA (Separating the cue and search display): 1000, 2500, or 4000 ms. With increasing display sizes, Target Presence: Present or Absent. Search Display Size: 6, 12, or 18 objects. response times increased more for target-absent trials, N=24 (1 dropped for excessive errors) P’s completed the full design 7 times (504 total test trials) F(2,44)=27.1, p<.001, η2=0.55 and errors increased more for target-present trials. The Maxim Analyses 5-Factor, within-subjects, repeated-measures ANOVA for F(2,44)=8.1, p<.001, η2=0.27 Median correct response times 1 picture 1000 words Potential speed-accuracy trade-off (although see Zenger & Fahle, 1997). Error rates When more is less! Cute kid. Male. Blonde. Caucasian. Blue eyes. Outside. Fair skin. Happy. Sunset. Red jacket. Plaid shirt. Wide aperture. Approximately 6 years old. Eye-length bangs. Impish grin. Slightly curly hair… = Greater effects of target-presence with Response Times: less information or pictures. More information is better when the cue is a picture and the target is present. F(2,44)=30.3, p<.001, η2=0.58 F(2,44)=8.8, p<.01, η2=0.28 F(1,22)=4.7, p<.05, η2=0.17 For Guiding Search, What’s Better? t(22)=1.4, p<.05, Cohen’s d=.18 Errors stabilize after the shortest SOA. Otherwise more doesn’t help. Wolfe and colleagues (2004) had participants search for colored bars amongst distractors. Participants received either a picture of the target or two words describing it. ts(22)<1.9, ns F(2,44)=30.3, p<.001, η2=0.58 = Errors: BIG RED Participants performed better with the picture. The maxim suggests, maybe there weren’t enough words. With picture cues, more information helps. Conclusions F(1,22)=19.5, p<.001, η2=0.47 t(22)=2.7, p<.05, Cohen’s d=.28 Manipulating Informativeness • More information doesn’t always help visual search. • Participants are able to complete their searches better with pictorial cues. • With more longer SOAs, RTs and error rates stabilize suggesting encoding is complete. With word cues, more information hurts. t(22)=3.2, p<.01, Cohen’s d=.47 Targets varied on three dimensions. Size: Big ( ) or small ( ) Color: Red ( ) or Green ( ) Tilt: Vertical ( ) or Horizontal ( ) More Informative Cues Indicated All Three Dimensions Less Informative Cues Indicated Only 2 Dimensions References: Wolfe, J. M., Horowitz, T. S., Kenner, N., Hyle, M., & Vasan, N. (2004). How fast can you change your mind? The speed of top-down guidance in visual search. Vision Research, 44, 1411-1426. Zenger, B., & Fahle, M. (1997). Missed targets are more frequent than false alarms, a model for error rates in visual search. Journal of Experimental Psychology: Human Perception and Performance, 23, 1783-1791. BIG RED HORIZONTAL BIG HORIZONTAL