Chris N. L. Olivers

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Search for a colour-form conjunction target can be facilitated by presenting one set of distractors prior to the second set of distractors and the target: the preview benefit (Watson & Humphreys, 1997). The early presentation of one set of distractors enables them to be efficiently filtered from search. We report two studies investigating the time course of(More)
Successful survival in a competitive world requires the employment of efficient procedures for selecting new in preference to old information. Recent behavioral studies have shown that efficient selection is dependent not only on properties of new stimuli but also on an intentional bias that we can introduce against old stimuli. Event-related analysis of(More)
We used a probe dot procedure to examine the time course of attention in preview search (Watson & Humphreys, 1997). Participants searched for an outline red vertical bar among other new red horizontal bars and old green vertical bars, superimposed on a blue background grid. Following the reaction time response for search, the participants had to decide(More)
It is widely assumed that symmetry is an important visual primitive, probably encoded without the need for attention. Julesz's (1981) definition of effortless perception, which states that any stimulus property perceived for exposure durations of 160 msec or less is detected preattentively, contributed greatly to this belief. Single pattern studies confirm(More)
Visual search for a unique stimulus is often faster when the feature defining this target is repeated. Recent research has related this feature priming to ambiguity: priming effects appear stronger when the search target is perceptually ambiguous, as when the search array contains a salient distractor. Here we link the ambiguity that underlies feature(More)
We argue that cognitive neuroscience can contribute not only information about the neural localization of processes underlying visual search, but also information about the functional nature of these processes. First we present an overview of recent work on whether search for form colour conjunctions is constrained by processes involved in binding across(More)
A simple method is presented for optimizing the efficiency of drawing line stimuli in Turbo Pascal. It involves the substitution of Rectangle and Bar commands for Line commands and results in time savings of up to 90%. The savings are most consistent for horizontal lines, although some savings may also be made for vertical lines. The effects of different(More)
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