A well-established phenomenon in the study of attention is the attentional blink-a deficit in reporting the second of two targets when it occurs 200-500 msec after the first. Although the effect has been shown to be robust in a variety of task conditions, not every individual participant shows the effect. We measured electroencephalographic activity for "nonblinkers" and "blinkers" during execution of a task in which two letters had to be detected in an sequential stream of digit distractors. Nonblinkers showed an earlier P3 peak, suggesting that they are quicker to consolidate information than are blinkers. Differences in frontal selection positivity were also found, such that nonblinkers showed a larger difference between target and distractor activation than did blinkers. Nonblinkers seem to extract target information better than blinkers do, allowing them to reject distractors more easily and leaving sufficient resources available to report both targets.

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The traditional distinction between exogenous and endogenous attentional control has recently been enriched with an additional mode of control, termed “selection history.” Recent findings have indicated, for instance, that previously rewarded or punished stimuli capture more attention than their physical attributes would predict. As such, the value that is associated with certain stimuli modulates attentional capture. This particular influence has also been shown for endogenous attention. Although recent leads have emerged, elucidating the influences of reward on exogenous and endogenous attention, it remains unclear to what extent exogenous attention is modulated by reward when endogenous attention is already deployed. We used a Posner cueing task in which exogenous and endogenous cues were presented to guide attention. Crucially, the exogenous cue also indicated the reward value. That is, the color of the exogenous cue indicated how much reward could be obtained on a given trial. The results showed main effects of endogenous and exogenous attention (i.e., speeded reaction times when either cue was valid, as compared to when it was invalid). Crucially, an interaction between exogenous cue validity and reward level was observed, indicating that reward-based associative-learning processes rapidly influence attentional capture, even when endogenous attention has been actively deployed.

Humans can quickly and accurately recognize objects within briefly presented natural scenes. Previous work has provided evidence that scene context contributes to this process, demonstrating improved naming of objects that were presented in semantically consistent scenes (e.g., a sandcastle on a beach) relative to semantically inconsistent scenes (e.g., a sandcastle on a football field). The current study was aimed at investigating which processes underlie the scene consistency effect. Specifically, we tested: (1) whether the effect is due to increased visual feature and/or shape overlap for consistent relative to inconsistent scene-object pairs; and (2) whether the effect is mediated by attention to the background scene. Experiment 1 replicated the scene consistency effect of a previous report (Davenport and Potter, 2004). Using a new, carefully controlled stimulus set, Experiment 2 showed that the scene consistency effect could not be explained by low-level feature or shape overlap between scenes and target objects. Experiments 3a and 3b investigated whether focused attention modulates the scene consistency effect. By using a location cueing manipulation, participants were correctly informed about the location of the target object on a proportion of trials, allowing focused attention to be deployed toward the target object. Importantly, the effect of scene consistency on target object recognition was independent of spatial attention, and was observed both when attention was focused on the target object and when attention was focused on the background scene. These results indicate that a semantically consistent scene context benefits object recognition independently of the focus of attention. We suggest that the scene consistency effect is primarily driven by global scene properties, or “scene gist”, that can be processed with minimal attentional resources.

In the present study, we investigated the conditions in which rewarded distractors have the ability to capture attention, even when attention is directed toward the target location. Experiment 1 showed that when the probability of obtaining reward was high, all salient distractors captured attention, even when they were not associated with reward. This effect may have been caused by participants suboptimally using the 100%-valid endogenous location cue. Experiment 2 confirmed this result by showing that salient distractors did not capture attention in a block in which no reward was expected. In Experiment 3, the probability of the presence of a distractor was high, but it only signaled reward availability on a low number of trials. The results showed that those very infrequent distractors that signaled reward captured attention, whereas the distractors (both frequent and infrequent ones) not associated with reward were simply ignored. The latter experiment indicates that even when attention is directed to a location in space, stimuli associated with reward break through the focus of attention, but equally salient stimuli not associated with reward do not.

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The present study rigorously tests whether an arbitrary stimulus that signals threat affects attentional selection and perception. Thirty-four volunteers completed a spatial-emotional cueing paradigm to examine how perceptual sensitivity (d') and response times (RTs) were affected by a threatening stimulus. On each side of fixation, 2 colored circles were presented as cues, followed by 2 Gabor patches, 1 of which was tilted and served as target. The color of 1 of the cues was paired with an electric shock, while others remained neutral. The target could be presented at the location of the threat-associated cue (Valid), at the opposite side (Invalid), or following neutral cues. Stimulus onset asynchrony (SOA) between cue and target was either 100 ms or 1,000 ms. Results showed increased perceptual sensitivity (d') and faster RTs for targets appearing at the Valid location relative to the Invalidly cued location, suggesting that immediately after cue presentation, attention was captured by the threat-associated cue. Crucially, following this initial exogenous capture, there was also enhanced perceptual sensitivity at the long SOA, suggesting that attention lingered volitionally at the location that previously contained the threat-associated stimulus. The current results show an effect of threatening stimuli on perceptual sensitivity, providing unequivocal evidence that threatening stimuli modulate the efficacy of sensory processing. (PsycINFO Database Record