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Reflexive and voluntary orienting of visual attention: time course of activation and resistance to interruption.
Effects of advance cues indicating the probable locations of targets that they had to discriminate and localize support a model for spatial attention with distinct but interacting reflexive and voluntary orienting mechanisms.
Visual search for singleton feature targets within and across feature dimensions
Three experiments investigated visual search for singleton feature targets and found that pop-out requires (or involves) knowledge of the particular dimension in which an odd-one-out target differs from the nontargets; furthermore, that knowledge is acquired through the elimination of dimensions not containing a target.
Searching for unknown feature targets on more than one dimension: Investigating a “dimension-weighting” account
The proposed adimension-weighting account showed that both tasks involveweight shifting, though (explicitly) discerning the dimension of a target requires some process additional to simply detecting its presence; and the intertrial facilitation is indeed (largely) dimension specific rather than feature specific in nature.
Reflexive and voluntary orienting of visual attention: time course of activation and resistance to interruption
To study the mechanisms underlying covert orienting of attention in visual space, subjects were given advance cues indicating the probable locations of targets that they had to discriminate and
The effect of visual attention on peripheral discrimination thresholds in single and multiple element displays.
There is an early ‘automatic’ and a later ‘controlled’ mechanism of spatial orienting, which differ in their interruptability by competing strimuli, e.g. targets at uncued locations.
Evidence of separable spatial representations in a virtual navigation task.
Findings support the assumption of coexisting spatial representations during navigation by demonstrating that sparse visual flow was sufficient for accurate path integration and finding subjects to prefer a distinct egocentric or allocentric reference frame to solve the task.
Attentional capture by salient color singleton distractors is modulated by top-down dimensional set.
Three experiments examined whether salient color singleton distractors automatically interfere with the detection singleton form targets in visual search, and revealed distracting interference to vary as a function of both the initial experience with distractors and the incentive to suppress them, suggesting that distractor interference is top-down modulable.
Human Brain Dynamics Accompanying Use of Egocentric and Allocentric Reference Frames during Navigation
In subjects who respond to a postnavigation homing challenge in distinctly different ways, stronger activation of retrosplenial and related cortical areas during turns support a continuous translation of egocentrically experienced visual flow into an allocentric model of their virtual position and movement.
Electrophysiological markers of visual dimension changes and response changes.
The present findings strengthen the DWA by indicating a perceptual origin of dimension change costs in visual search by focusing on specific event-related brain potential components (directly linkable to perceptual and response-related processing) during a compound search task.
Cross-trial priming in visual search for singleton conjunction targets: Role of repeated target and distractor features
Two experiments were conducted to examine whether the search response time (RT) facilitation on target-present trials results from repetition of target-defining features, distractor features, or both, and indicate that cross-trial priming effects in conjunctive visual search result mainly from the repetition of distractor, rather than target, features.