Out of control: attentional selection for orientation is thwarted by properties of the underlying neural mechanisms

Ensemble perception without attention depends upon attentional control settings

People are able to rapidly extract summary statistical information about common patterns, or ensembles, that may exist in a scene, such as repeated textures or colors. Here we examined the extent to which such an ensemble perception can occur in the absence of focal visual attention using a method that has some advantages over methods previously used to study the issue. In particular, we assessed the extent to which ensembles can be processed without attention by measuring the indirect effect of a to-be-ignored ensemble on judgments of an attended ensemble. The results show that ensembles outside the focus of attention do influence judgments of attended ensembles when the to-be-ignored ensemble contains summary statistics that match a sought-for target category. Thus, an attentional control setting for specific summary statistical information permits the processing of ensembles outside of focal attention, facilitating the rapid perception of visual scenes.

Three visual working memory representations simultaneously control attention

How many items can we store in visual working memory while simultaneously conducting a visual search? Previous research has proposed that during concurrent visual search, only one visual working memory representation can be activated to directly influence attention. This previous research suggests that other visual working memory representations are "accessory items", which have little direct influence on attention. However, recent findings provided evidence that not one, but two visual working memory representations can capture attention and interfere with concurrent visual search. We successfully replicate these findings, and further test whether the capacity of visual working memory during visual search extends to not two, but three representations that influence attention directly. We find evidence that three visual working memory representations can simultaneously control attention.

Two visual working memory representations simultaneously control attention

It has been proposed that only one visual working memory (VWM) representation can be activated to influence perception directly, whereas other VWM representations are accessory items which have little influence on visual selection. The sole active VWM representation might reflect a fundamental bottleneck in the information processing of human beings. However, the present study showed that each of two VWM representations can capture attention and interfere with concurrent visual search. In addition, each of two VWM representations can interfere with concurrent visual search as much as can a single cued VWM representation. Moreover, when two memory-matching distractors appear in visual search, two VWM representations produce a larger memory-driven capture effect than a single memory-matching distractor. Thus, two VWM representations can simultaneously control attention.

Social comparison modulates reward-driven attentional capture

It is well established that attention can be captured by task irrelevant and non-salient objects associated with value through reward learning. However, it is unknown whether social comparison influences reward-driven attentional capture. The present study created four social contexts to examine whether different social comparisons modulate the reward-driven capture of attention. The results showed that reward-driven attentional capture varied with different social comparison conditions. Most prominently, reward-driven attentional capture is dramatically reduced in the disadvantageous social comparison context, in which an individual is informed that the other participant is earning more monetary reward for performing the same task. These findings suggest that social comparison can affect the reward-driven capture of attention.

Hold the future, let the past go: attention prefers the features of future targets

Previous studies have shown that attention can be captured by task-irrelevant distractors under the guidance of attentional control settings. However, it is unknown whether people can establish an attentional control setting (ACS) for a sequence of distinct events. The present study tested that question by asking observers to expect a sequence of two colored targets in a specific order. The results show that irrelevant distractors that matched either the color of the first expected target or that of the second target captured attention. Thus observers are unable to temporarily suppress the color of the future target in their ACS. However, the temporal order of targets is still useful for guiding attention: Observers were able to abandon the color of the first target and maintain an ACS for the second one as long as there was a sufficient time interval between the two targets.

Contingent orienting or contingent capture: a size singleton matching the target-distractor size relation cannot capture attention

In the present study, we examined whether a peripheral size-singleton distractor that matches the target-distractor size relation can capture attention and disrupt central target identification. Three experiments consistently showed that a size singleton that matches the target-distractor size relation cannot capture attention when it appears outside of the attentional window, even though the same size singleton produces a cuing effect. In addition, a color singleton that matches the target color, instead of a size singleton that matches the target-distractor size relation, captures attention when it is outside of the attentional window. Thus, a size-relation-matched distractor is much weaker than a color-matched distractor in capturing attention and cannot capture attention when the distractor appears outside of the attentional window.

Dual processes of oculomotor capture by abrupt onset: rapid involuntary capture and sluggish voluntary prioritization

The present study showed that there are two distinctive processes underlying oculomotor capture by abrupt onset. When a visual mask between the cue and the target eliminates the unique luminance transient of an onset, the onset still attracts attention in a top-down fashion. This memory-based prioritization of onset is voluntarily controlled by the knowledge of target location. But when there is no visual mask between the cue and the target, the onset captures attention mainly in a bottom-up manner. This transient-driven capture of onset is involuntary because it occurs even when the onset is completely irrelevant to the target location. In addition, the present study demonstrated distinctive temporal characteristics for these two processes. The involuntary capture driven by luminance transients is rapid and brief, whereas the memory-based voluntary prioritization of onset is more sluggish and long-lived.