A typical way to investigate the relationship between spatial attention and the programming of an eye movement is with a dual-task. Here, participants simultaneously make an eye movement in one direction and discriminate a target at the same or a different location. Results of these tasks consistently find that performance is best at the goal of an upcoming eye movement. It is less clear, however, the extent to which spatial attention can shift independently of the programmed saccade. In this paper, for the first time, we use an evidence accumulation model to examine this longstanding question. Specifically, across two studies, we quantify the relative contributions of spatial attention and saccade preparation in a perceptual dual-task. Our results establish that there is a unique and measurable effect of spatial attention away from the saccade goal, and, interestingly, that the relative magnitude of this effect varies by cue type. There is a larger influence of spatial attention when a peripheral rather than a central cue is employed. We suggest that these results support the claim that each form of orienting is mediated by a distinct underlying mechanism.

One common way to investigate the relationship between eye movements and attention is to pair the cueing paradigm with a saccadic dual-task. Here eye movements are directed to one location in the visual field, while a spatial cue simultaneously directs attention to the same or a different location. The magnitude of the cueing effect is then compared between trials where gaze is maintained at fixation and trials where eye movements are prepared. As these comparisons typically occur across blocked single and dual-task conditions, it is difficult to address possible confounds due to changes in response caution. In this paper we use evidence accumulation modeling to remove this confound and extract a measure of orienting that can be used to quantify and compare the influence of spatial attention across four different manipulations of eye movements: 2 that require fixation and 2 that require saccade preparation. The results demonstrate that the magnitude of the cueing effect is similar regardless of eye movement condition or perceptual task. The perceptual benefit associated with preparing a saccade, in contrast, was found to vary by perceptual task. Taken together these results establish that spatial attention and saccade preparation are separable and, we suggest, mediated by distinct underlying mechanisms.

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Eye gaze plays dual perceptual and social roles in everyday life. Gaze allows us to select information for further processing, whilst also indicating to others where we are attending. There are situations, however, where revealing the locus of our attention to others is not adaptive, such as when playing competitive sport or confronting an aggressor. It is in these circumstances that covert shifts in attention are assumed to play an essential role. Despite this assumption, few studies have explored the relationship between covert shifts in attention and eye movements within social contexts. In the present study, we explore this relationship using the saccadic dual-task in combination with the gaze-cueing paradigm. Across two experiments, participants either prepared an eye movement or fixated centrally. At the same time, spatial attention was cued with a social (gaze) or non-social (arrow) cue. We used an evidence accumulation model to quantify the relative contributions of both spatial attention and eye movement preparation to performance on a Landolt gap detection task. Importantly, this computational approach allowed us to extract a measure of performance that could unambiguously compare covert and overt orienting in social and non-social cueing tasks for the first time. Our results revealed that covert and overt orienting make separable contributions to perception during gaze-cueing, but that the mechanisms that underlie these attention shifts are similar to those that mediate non-social cueing. Therefore, consistent with a domain-general interpretation to orienting, our results suggest that covert and overt shifts in attention are mediated by independent underlying mechanisms that are invariant to social context.

Eye gaze plays dual perceptual and social roles in everyday life. Gaze allows us to select information, while also indicating to others where we are attending. There are situations, however, where revealing the locus of our attention is not adaptive, such as when playing competitive sports or confronting an aggressor. It is in these circumstances that covert shifts in attention are assumed to play an essential role. Despite this assumption, few studies have explored the relationship between covert shifts in attention and eye movements within social contexts. In the present study, we explore this relationship using the saccadic dual-task in combination with the gaze-cueing paradigm. Across two experiments, participants prepared an eye movement or fixated centrally. At the same time, spatial attention was cued with a social (gaze) or non-social (arrow) cue. We used an evidence accumulation model to quantify the contributions of both spatial attention and eye movement preparation to performance on a Landolt gap detection task. Importantly, this computational approach allowed us to extract a measure of performance that could unambiguously compare covert and overt orienting in social and non-social cueing tasks for the first time. Our results revealed that covert and overt orienting make separable contributions to perception during gaze-cueing, and that the relationship between these two types of orienting was similar for both social and non-social cueing. Therefore, our results suggest that covert and overt shifts in attention may be mediated by independent underlying mechanisms that are invariant to social context.