In a variety of settings we encounter pigeons searching for food concealed among  assorted inedible objects. Efficient foraging requires appropriate perceptual and cognitive strategies, and certain of those adopted by pigeons resemble selective processes employed by humans in laboratory detection  tasks. For example, the birds are more likely to consume grains that are dissimilar to the background. Further, pigeons overselect grain types that are relatively abundant, an observation that suggests that they focus their attention on more probable targets.  The structure of their visual systems is well-suited to the search task; For example, specialized retinal areas serve their lower field of view, and a flexible accommodation mechanism allows them to focus on close objects. Research using artificial search displays has shed light on mechanisms that guide the pigeons' search. These techniques permit more precise control of important variables such as form similarity. In our lab birds peck at designated target letters embedded among non-target symbols displayed on a computer screen (See Figure 1). Detection is more efficient, not only for more probable targets, but also when specific cues inform the bird of the forthcoming target's identity. Like humans, pigeons search more rapidly for expected items, and they can use varied types of information to form such expectancies. These associations are acquired in a manner that seems to depart from the usual rules of conditioning.

Chapter Outline & Navigation I. Introduction II. Search          Visual search            Perceptual search            Memory search III.  Attention and the Search Image           Human attention            Avian attention IV.  References

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