Steven B. Most

What You See Is What You Set: Sustained Inattentional Blindness and the Capture of Awareness.

This article reports a theoretical and experimental attempt to relate and contrast 2 traditionally separate research programs: inattentional blindness and attention capture. Inattentional blindness refers to failures to notice unexpected objects and events when attention is otherwise engaged. Attention capture research has traditionally used implicit indices (e.g., response times) to investigate automatic shifts of attention. Because attention capture usually measures performance whereas inattentional blindness measures awareness, the 2 fields have existed side by side with no shared theoretical framework. Here, the authors propose a theoretical unification, adapting several important effects from the attention capture literature to the context of sustained inattentional blindness. Although some stimulus properties can influence noticing of unexpected objects, the most influential factor affecting noticing is a persons own attentional goals. The authors conclude that many--but not all--aspects of attention capture apply to inattentional blindness but that these 2 classes of phenomena remain importantly distinct.

How not to be Seen: The Contribution of Similarity and Selective Ignoring to Sustained Inattentional Blindness

When people attend to objects or events in a visual display, they often fail to notice an additional, unexpected, but fully visible object or event in the same display. This phenomenon is now known as inattentional blindness. We present a new approach to the study of sustained inattentional blindness for dynamic events in order to explore the roles of similarity, distinctiveness, and attentional set in the detection of unexpected objects. In Experiment 1, we found that the similarity of an unexpected object to other objects in the display influences attentional capture: The more similar an unexpected object is to the attended items, and the greater its difference from the ignored items, the more likely it is that people will notice it. Experiment 2 explored whether this effect of similarity is driven by selective ignoring of irrelevant items or by selective focusing on attended items. The results of Experiment 3 suggest that the distinctiveness of the unexpected object alone cannot entirely account for the similarity effects found in the first two experiments; when attending to black items or white items in a dynamic display, nearly 30% of observers failed to notice a bright red cross move across the display, even though it had a unique color, luminance, shape, and motion trajectory and was visible for 5 s. Together, the results suggest that inattentional blindness for ongoing dynamic events depends both on the similarity of the unexpected object to the other objects in the display and on the observers attentional set.

Attentional rubbernecking: cognitive control and personality in emotion-induced blindness.

Emotional stimuli often attract attention, but at what cost to the processing of other stimuli? Given the potential costs, to what degree can people override emotion-based attentional biases? In Experiment 1, participants searched for a single target within a rapid serial visual presentation of pictures; an irrelevant, emotionally negative or neutral picture preceded the target by either two or eight items. At the shorter lag, negative pictures spontaneously induced greater deficits in target processing than neutral pictures did. Thus, attentional biases to emotional information induced a temporary inability to process stimuli that people actively sought. Experiment 2 revealed that participants could reduce this effect through attentional strategy, but that the extent of this reduction was related to their level of the personality traitharm avoidance. Participants lower in harm avoidance were able to reduce emotioninduced blindness under conditions designed to facilitate the ignoring of the emotional stimuli. Those higher in harm avoidance were unable to do so.

The naked truth: Positive, arousing distractors impair rapid target perception

Emotional stimuli tend to capture and hold attention more than non-emotional stimuli do. Aversive pictures have been found to impair perception of visual targets even after the emotional information has disappeared. The benefits of such interlinked emotion and attention systems have sometimes been discussed within an evolutionary framework, with a survival advantage attributed to early detection of threatening stimuli. However, consistent with recent suggestions that attention is drawn to arousing stimuli regardless of whether they are positive or negative, the current investigation found that erotic distractors—generally rated as both pleasing and arousing—consistently elicited a transient “emotion-induced blindness” similar to that caused by aversive distractors (Experiment 1). This effect persisted despite performance-based monetary incentives to ignore the distractors (Experiment 2), and following attentional manipulations that reduced interference from aversive images (Experiment 3). The findings indicate that positively arousing stimuli can spontaneously cause emotion-induced deficits in visual processing, just as aversive stimuli can.

An emotion-induced attentional blink elicited by aversively conditioned stimuli.

The current study examines whether aversively conditioned stimuli can modulate attention to such a degree that they impair the perception of subsequently presented nonemotional targets. In the initial phase of this study, participants viewed 3 categories of photographs, 1 of which was paired with an aversive noise. Following conditioning, participants searched for a target embedded within a series of 17 rapidly presented images on each trial. Critically, a conditioned or unconditioned item from the initial phase appeared 200 ms or 800 ms before the target. At 200-ms lags but not 800-ms lags, the conditioned images impaired target detection relative to the other distractors. Thus, temporary visual deficits can be induced by otherwise neutral distractors whose aversive associations have only recently been learned.

Feature-based attentional set as a cause of traffic accidents

Voluntary and relatively involuntary subsystems of attention often compete. On one hand, people can intentionally “tune” attention for features that then receive visual priority; on the other hand, more reflexive attentional shifts can “short-circuit” top-down control in the face of urgent, behaviourally relevant stimuli. Thus, it is questionable whether voluntary attentional tuning (i.e., attentional set) can affect ones ability to respond to unexpected, urgent information in the real world. We show that the consequences of such tuning extend to a realistic, safety-relevant scenario. Participants drove in a first-person driving simulation where they searched at every intersection for either a yellow or blue arrow indicating which way to turn. At a critical intersection, a yellow or blue motorcycle—either matching or not matching drivers’ attentional set—suddenly veered into drivers’ paths and stopped in their way. Collision rates with the motorcycle were substantially greater when the motorcycle did not match drivers’ attentional sets.

Increasing negative emotions by reappraisal enhances subsequent cognitive control: A combined behavioral and electrophysiological study

To what degree do cognitively based strategies of emotion regulation impact subsequent cognitive control? Here, we investigated this question by interleaving a cognitive task with emotion regulation trials, where regulation occurred through cognitive reappraisal. In addition to obtaining self-reports of emotion regulation, we used the late positive potential (LPP) of the event-related brain potential as an objective index of emotion regulation. On each trial, participants maintained, decreased, or increased their emotional response to an unpleasant picture and then responded to a Stroop stimulus. Results revealed that (1) the magnitude of the LPP was decreased with reappraisal instructions to decrease negative emotion and were enhanced with reappraisal instructions to increase negative emotion; (2) after cognitive reappraisal was used to increase the intensity of negative emotion, RT interference in the subsequent Stroop trial was significantly reduced; and (3) increasing negative emotions by reappraisal also modulated the cognitive control-related sustained potential. These results suggest that increasing negative emotions by cognitive reappraisal heightens cognitive control, which may be sustained for a short time after the regulation event.

Dissociating Spatial Attention and Awareness in Emotion-Induced Blindness

Emotional stimuli attract spatial attention, sometimes improving perception at their location. But they also can disrupt awareness of targets at their location, a phenomenon known as emotion-induced blindness. Such discrepant findings might reflect the impact of emotional stimuli on different perception mechanisms. We dissociated spatial attention and awareness by investigating the spatial distribution of emotion-induced blindness. Participants searched for a target within two simultaneous rapid streams of pictures, one of which could also contain a preceding emotional distractor. When targets were followed by additional stream items, emotion-induced blindness occurred only at the location of the distractor. However, when no items appeared after the target, so that it could persist in iconic memory and its temporal position was easily discernible, emotional disruption of target perception was more robust away from the distractor’s location than at the distractor’s location. The results suggest that although emotional distractors attract spatial attention, they inhibit identification of competing items potentially linked to the same spatiotemporal position.

Cognitive control and counterproductive oculomotor capture by reward-related stimuli

Two experiments investigated the extent to which value-modulated oculomotor capture is subject to top-down control. In these experiments, participants were never required to look at the reward-related stimuli; indeed, doing so was directly counterproductive because it caused omission of the reward that would otherwise have been obtained. In Experiment 1, participants were explicitly informed of this omission contingency. Nevertheless, they still showed counterproductive oculomotor capture by reward-related stimuli, suggesting that this effect is relatively immune to cognitive control. Experiment 2 more directly tested whether this capture is controllable by comparing the performance of participants who either had or had not been explicitly informed of the omission contingency. There was no evidence that value-modulated oculomotor capture differed between the two conditions, providing further evidence that this effect proceeds independently of cognitive control. Taken together, the results of the present research provide strong evidence for the automaticity and cognitive impenetrability of value-modulated attentional capture.

Don't look back: Retroactive, dynamic costs and benefits of emotional capture

When people search for targets within rapid streams of images, irrelevant emotional distractors—relative to neutral distractors—spontaneously demand attention and impair subsequent target detection, an effect that can be likened to an emotion-induced “attentional blink”. But what happens when emotional distractors appear after a target has already come and gone? Here, we describe new findings of retroactive emotion-induced effects on target awareness. First, emotion-induced impairments of target awareness extended even to targets that appeared immediately before emotional distractors (Experiment 1). Second, when targets preceded distractors by two items—rather than by one item—negative distractors led to enhanced target processing relative to when distractors were neutral (Experiment 2). In contrast, when a target appeared after an emotional distractor, target awareness was impaired regardless of whether it was the first or second subsequent item. These results potentially implicate separable impacts of emotion on target processing, which can be distinguished by their facilitatory versus disruptive effects and by their temporal dynamics.