It has recently been proposed that in searching for a target defined as conjunction of two or more separable features, attention must be paid serially to each stimulus display. Support this comes from studies which subjects searched shared single feature with different kinds distractor items (e.g., red O field black Os and Ns). Reaction time increased linearly display size. We argue design may obscure evidence selectivity search. In an experiment the numbers distractors were unconfounded, we...

Visual attention may be voluntarily directed to particular locations or features (voluntary control), it captured by salient stimuli, such as the abrupt appearance of a new perceptual object (stimulus-driven control). Most often, however, deployment is result dynamic interplay between voluntary attentional control settings (e.g., based on prior knowledge about target's location color) and degree which stimuli in visual scene match these settings. Consequently, nontarget items that share...

It is often assumed that the efficient detection of salient visual objects in search reflects stimulus-driven attentional capture. Evidence for this assumption, however, comes from tasks which object task relevant and therefore may elicit a deliberate deployment attention. In 9 experiments, participants searched nonsalient target (vertical among tilted bars). each display, 1 bar was highly different dimension (e.g., color or motion). When elements coincided only rarely, reducing incentive to...

Many theories of visual perception assume that before attention is allocated within a scene, information parsed according to the Gestalt principles organization. This assumption has been challenged by experiments in which participants were unable identify what grouping patterns had occurred background primary-task displays (A. Mack, B. Tang, R. Tuma, S. Kahn, & I. Rock, 1992). In present study, reported 2 horizontal lines was longer. Dots background, if grouped, formed similar Ponzo illusion...

Attentional allocation in feature-search mode (W. F. Bacon & H. E. Egeth, 1994) is thought to be solely determined by top-down factors, with no role for stimulus-driven salience. The authors reassessed this conclusion using variants of the spatial cuing and rapid serial visual presentation paradigms developed C. L. Folk colleagues (C. Folk, R. W. Remington, J. Johnston, 1992; A. B. Leber, 2002). They found that (a) a nonsingleton distractor possesses target feature produces attentional...

Two experiments indicate that reaction time and accuracy are not always equivalent measures of the underlying processes involved in recognition visually presented letters. In conjunction with results previous work, our research suggests following generalizations: (a) Under data-limited viewing conditions (the short exposure durations typical tachistoscopic task), response is sensitive to early perceptual interference between target noise items, whereas more later interference. (b)...

Previous research indicates that prior information about a target feature, such as its color, can speed search. Can search also be speeded by knowing what will not look like? In the two experiments reported here, participants searched for letters. Prior to viewing displays, were prompted either with color in which one or more nontarget letters would appear (ignore trials) no display (neutral trials). Critically, when given consistent ignore duration of experiment, compared they information,...

Ss indicated whether pairs of simultaneously presented objects were "same" or "different." In Experiments 1, 2, and 3 the stimuli letters, familiarity was manipulated by showing letters in either an upright upside-down orientation. 4 5 trigrams, rotation selection according to rated meaningfulness. Analysis reaction times that familiar responded more quickly than unfamiliar pairs; however, this true only for judgments, not "different" judgments. addition, Experiment influenced discrimination...

Previous research suggests that observers can suppress salient-but-irrelevant stimuli in a top-down manner. However, one question left unresolved is whether such suppression is, fact, solely due to distractor-feature or it instead also reflects some degree of target-feature enhancement. The present study ( N = 60) addressed this issue. On search trials (70% trials), participants searched for shape target when an irrelevant color singleton was either absent; performance better present....