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High-acuity foveal processing is vital for human vision. Nonetheless, little is known about how the preparation of large-scale rapid eye movements (saccades) affects visual sensitivity in the center of gaze. Based on findings from passive fixation tasks, we hypothesized that during saccade preparation, foveal processing anticipates soon-to-be fixated visual features. Using a dynamic large-field noise paradigm, we indeed demonstrate that defining features of an eye movement target are enhanced in the pre-saccadic center of gaze. Enhancement manifested as higher Hit Rates for foveal probes with target-congruent orientation and a sensitization to incidental, target-like orientation information in foveally presented noise. Enhancement was spatially confined to the center of gaze and its immediate vicinity, even after parafoveal task performance had been raised to a foveal level. Moreover, foveal enhancement during saccade preparation was more pronounced and developed faster than enhancement during passive fixation. Based on these findings, we suggest a crucial contribution of foveal processing to trans-saccadic visual continuity: Foveal processing of saccade targets commences before the movement is executed and thereby enables a seamless transition once the center of gaze reaches the target.

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Saccadic eye movements cause large-scale transformations of the image falling on the retina. Rather than starting visual processing anew after each saccade, the visual system combines post-saccadic information with visual input from before the saccade. Crucially, the relative contribution of each source of information is weighted according to its precision, consistent with principles of optimal integration. We reasoned that, if pre-saccadic input is maintained in a resource-limited store, such as visual working memory, its precision will depend on the number of items stored, as well as their attentional priority. Observers estimated the color of stimuli that changed imperceptibly during a saccade, and we examined where reports fell on the continuum between pre- and post-saccadic values. Bias toward the post-saccadic color increased with the set size of the pre-saccadic display, consistent with an increased weighting of the post-saccadic input as precision of the pre-saccadic representation declined. In a second experiment, we investigated if transsaccadic memory resources are preferentially allocated to attentionally prioritized items. An arrow cue indicated one pre-saccadic item as more likely to be chosen for report. As predicted, valid cues increased response precision and biased responses toward the pre-saccadic color. We conclude that transsaccadic integration relies on a limited memory resource that is flexibly distributed between pre-saccadic stimuli.

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A policeman overlooks his colleagues assaulting an innocent passerby and is wrongly accused of obscuring their misjudgments, a car driver fails to notice a scooter and causes an accident, and-as if these incidents on their own did not make for a highly unfortunate Saturday-you lose sight of your tent at a festival and find yourself trudging through muddy puddles in search for green tarp. Although seemingly unconnected, all of these events illustrate a fundamental property of the human visual system: We consciously perceive only small chunks of the visual world that surrounds us in all its detail. In his book How Attention Works, Stefan van der Stigchel sets out to explain how visual attention shapes our experience of the environment and argues that a selective attentional focus can have detrimental consequences when misguided but ultimately enables us to function effectively in a world of distraction. Across seven chapters, van der Stigchel provides a broad overview of visual attention and its interplay with perception, action, and memory. Ingeniously, he coins the term "attention architects." It describes all those strategically guiding our focus of attention-website designers, teachers, traffic engineers, advertising agents, magicians, and perhaps youwho attempt to influence what aspects of the world we perceive or fail to register. In a casual tone, van der Stigchel reviews the science behind what, in these trades, is often based on intuition, experience, or training. He describes pre-attentive limitations on perception and illustrates the existence of an attentional filter mechanism that shapes how we search visual scenes. The author then outlines the interplay between visual attention and eye movements and explains how implicit long-term memory resulting from prior exposure to a situation can guide the spotlight of attention. In his final chapter, he describes various slips of attention-both pathological and nonpathological-and concludes that "it is when things go wrong that we realize that our ability to see the entire picture is just an illusion" (p. 115). Van der Stigchel does not shy away from classical vision science terms. Among others, his book includes explanations of salience, luminance adaptation, crowding, change blindness, pop-out and serial search, inhibition of return, and cueing. While these concepts are well known to the vision science community, How Attention Works will certainly appeal to a wider audience including undergraduate students and complete novices. In fact, an

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We previously demonstrated that during the preparation of a large-scale saccadic eye movement, defining features of the eye movement target (i.e., its orientation) are anticipated in pre-saccadic foveal vision (Kroell & Rolfs, 2022). Here, we show that the conspicuity of orientation information at the saccade target location influences the magnitude and time course of foveal enhancement. As in our previous study, observers prepared a saccade to a peripheral orientation signal (the target) while monitoring the appearance of a second orientation signal (the probe) in their pre-saccadic center of gaze. The probe appeared in 50% of trials and either had the same orientation as the target (congruent) or a different orientation (incongruent). In the current study, we manipulated the opacity of the target against the 1/f background noise in four logarithmic steps from 25 to 90%. An increase in opacity translates to an increase in luminance contrast and the signal-to-noise ratio of orientation information within the target region. We made three main observations: First, foveal Hit Rates for target-congruent and incongruent probes decreased as target opacity increased, presumably since attention was increasingly drawn to the target the more salient it became. Crucially, foveal enhancement defined as the difference between congruent and incongruent Hit Rates increased with opacity. Second, foveal enhancement emerged earlier as target opacity increased, likely since the peripheral target was processed faster at higher contrasts. Third, unlike the difference in Hit Rates, the difference in False Alarm Rates did not vary with opacity. Instead, reverse correlations suggest that at higher target opacities, False Alarms were increasingly triggered by signal, that is, by incidental orientation information in the foveal noise. Beyond providing new mechanistic insights into active foveal processing, these findings are relevant for researchers planning to adapt our paradigm to study related questions. Presenting the saccade target at a high signal-to-noise ratio appears beneficial as congruency effects, especially when time-resolved, are most robustly detectable.