Detecting a target in a rapid serial visual presentation (RSVP) stream is more attentionally demanding than rejecting a distractor. However, background scenes coinciding with RSVP targets are better remembered than those coinciding with RSVP distractors, a paradoxical finding known as the attentional boost effect. But does the effect originate from the detection of the RSVP target or from the need to respond to it? To dissociate target detection from response, we investigated the attentional boost effect using a visual search task. Participants searched for a target among distractors while memorizing concurrently presented background objects. The search target could be present or absent. In different experiments, participants pressed a button on target-present trials only, target-absent trials only, or made a two-choice present/absent response. Results showed that objects paired with a Go response were better remembered than objects paired with a No-Go response, regardless of whether responses were associated with targetpresent or target-absent trials. This finding was replicated in experiments that required covert counting rather than an immediate button press response. These findings are the first to extend the attentional boost effect to visual search and demonstrate that the need to respond, not the detection of a search target, drives the effect for concurrently presented stimuli. Public Significance StatementDetecting and responding to behaviorally relevant events produces a transient temporal orienting response, which enhances the processing of concurrent stimuli. But what triggers this attentional boost? Previous studies investigating this effect have often confounded target detection with response. This study dissociates target detection from response using a visual search task. Results showed that response, rather than target detection, induces the attentional boost. The findings not only enrich theories about the attentional boost effect but also highlight the importance of response in modulating attention. They shed light on how people attend to behaviorally relevant moments (e.g., traffic lights changing color) in tasks like driving.

Under continuous dual-task conditions, participants show better memory for background information appearing at the same time as a response target in a concurrent task than for information appearing with a nontarget (the attentional boost effect, or ABE). While this effect has been demonstrated across a wide range of stimuli, few studies have examined the perceptual specificity of the memory difference. Here, we explored whether the ABE affects general category memory or perceptually specific exemplar memory. In an encoding phase, participants memorized images of objects presented in a continuous stream. At the same time, they pressed the space bar when a square appearing in the center of each image appeared in a target color, ignoring distractorcolored squares. The following four-alternative forced-choice memory test included the previously seen image, a perceptually distinct exemplar from the same category as the previously seen image, and two images from a new category. Regardless of whether images appeared during encoding three times (Experiment 1) or once (Experiment 2), participants recognized the correct exemplar more often during testing for images that had appeared with a target in encoding than for images that had appeared with a distractor. The difference in exemplar memory was not associated with a difference in false memories for within-category foils. This suggests that the ABE reflects modulation of perceptually detailed exemplar memory, which may be related to facilitation of pattern separation by detection-induced changes in cortical-hippocampal connectivity.

The novel coronavirus disease 2019 (COVID-19) has considerably heightened health and financial concerns for many individuals. Similar concerns, such as those associated with poverty, impair performance on cognitive control tasks. If ongoing concerns about COVID-19 substantially increase the tendency to mind wander in tasks requiring sustained attention, these worries could degrade performance on a wide range of tasks, leading, for example, to increased traffic accidents, diminished educational achievement, and lower workplace productivity. In two pre-registered experiments, we investigated the degree to which young adults’ concerns about COVID-19 correlated with their ability to sustain attention. Experiment 1 tested mainly European participants during an early phase of the pandemic. After completing a survey probing COVID-related concerns, participants engaged in a continuous performance task (CPT) over two, 4-min blocks, during which they responded to city scenes that occurred 90% of the time and withheld responses to mountain scenes that occurred 10% of the time. Despite large and stable individual differences, performance on the scene CPT did not significantly correlate with the severity of COVID-related concerns obtained from the survey. Experiment 2 tested US participants during a later phase of the pandemic. Once again, CPT performance did not significantly correlate with COVID concerns expressed in a pre-task survey. However, participants who had more task-unrelated thoughts performed more poorly on the CPT. These findings suggest that although COVID-19 increased anxiety in a broad swath of society, young adults are able to hold these concerns in a latent format, minimizing their impact on performance in a demanding sustained attention task.

Extensive research has shown that people are sensitive to statistical regularities of visual stimuli, such as a repeated sequence of object locations. Such learning, however, has primarily occurred for objects presented in isolation. Here, we tested whether sequence learning also manifested in complex displays. Using variants of the serial reaction time task, we asked participants to report the screen quadrant of a letter T, whose location followed a 12-trial sequence that repeated 30 times over 360 trials. In different experiments, we manipulated the nature of distractors surrounding the target. The T could appear in isolation, as a color singleton among distractors with fixed or variable locations, or as a conjunction search target. Sequence learning-expressed as elevated response time when the learned sequence was disrupted-decreased as spatial noise increased. Learning was robust when the T appeared in isolation or when it was surrounded by distractors that did not change locations. It was reduced in feature search and eliminated in conjunction search. These findings suggest that target locations are coded in relation to concurrently presented distractors. Variability in distractor locations disrupts target location sequence learning, revealing a limit to people's ability to extract and use spatiotemporal regularities in complex environments. Public Significance StatementThis study shows that people can learn from a repeated sequence of object locations, such as those encountered when visiting the same supermarkets or websites, and can use the repetitions to speed up response. However, the study also uncovers a limitation to sequence learning, especially when the displays are cluttered with distracting information that frequently changes locations. Learning diminishes in complex displays involving visual search. The finding highlights the importance of considering visual clutter and spatial consistency when designing navigable space, websites, and other user interfaces.

Using a novel gradual onset continuous performance task (gradCPT), recent research has uncovered a brain network of the sustained attention ability, demonstrating marked individual differences. Yet much about the cognitive processes that support performance on the gradCPT remains unknown. Here, we tested the importance of response inhibition and perceptual discrimination in the gradCPT. Participants monitored a continuous stream of natural scenes from two categories-cities and mountains-with a 9:1 ratio. In separate task blocks, they responded either to the frequent or the rare, yielding a response rate of either 90% or 10%. Performance was much worse, and declined more significantly over time, when the required response rate was higher. To test the role of stimulus onset, separate task blocks presented the scenes either gradually, with adjacent scenes blending into each other (gradCPT), or abruptly, with a single scene visible at a time (abruptCPT). Despite its increased complexity, the gradCPT yielded better performance than the abruptCPT, contradicting the perceptual complexity hypothesis and suggesting a detrimental role of the automaticity of responses to rhythmic stimuli in sustained attention. Further bolstering the role of response inhibition in the gradCPT, participants with superior inhibitory function, as assessed by the "stop-signal" task, did better on the gradCPT. These findings show that response inhibition contributes to the ability to sustain attention, especially in tasks that require frequent and repetitive responses as in assembly-line jobs.