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A briefly flashed peripheral cue has been shown to repulse the perceived position of a subsequently presented foveal probe - a bias called the Attentional Repulsion Effect (ARE). While this bias has originally been assumed to reflect attentional capturing by the cue, its attentional nature has recently been questioned. To investigate the ARE's attentional properties, we recorded microsaccades as an attentional marker in the ARE paradigm. Microsaccades, small fixational eye movements performed during fixation, have previously been described to reflect the dynamics of spatial attention deployment. Our results favor an attentional explanation for the ARE: In trials in which an ARE was found, microsaccades were directed more often toward the cue, presumably reflecting the covert shift of attention. In contrast, more cue-incongruent microsaccades were observed in trials in which no ARE was found. Therefore, both repulsion as well as measured microsaccade modulations, are most likely an outcome of the preceding shifts of covert attention., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Stimuli briefly flashed just before a saccade are perceived closer to the saccade target, a phenomenon known as saccadic compression of space. We have recently demonstrated that similar mislocalizations of flashed stimuli can be observed in the absence of saccades: brief probes were attracted towards a visual reference when followed by a mask. To examine the spatial profile of this new phenomenon of masked-induced compression, here we used a pair of references that draw the probe into the gap between them. Strong compression was found when we masked the probe and presented it following a reference pair, whereas little or no compression occurred for the probe without the reference pair or without the mask. When the two references were arranged vertically, horizontal mislocalizations prevailed. That is, probes presented to the left or right of the vertically arranged references were "drawn in" to be seen aligned with the references. In contrast, when we arranged the two references horizontally, we found vertical compression for stimuli presented above or below the references. Finally, when participants were to indicate the perceived probe location by making an eye movement towards it, saccade landing positions were compressed in a similar fashion as perceptual judgments, confirming the robustness of mask-induced compression. Our findings challenge pure oculomotor accounts of saccadic compression of space that assume a vital role for saccade-specific signals such as corollary discharge or the updating of eye position. Instead, we suggest that saccade- and mask-induced compression both reflect how the visual system deals with disruptions., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In a dual-task paradigm with a perceptual discrimination task and a concurrent saccade task, we examined participants' ability to make use of prior knowledge of a critical property of the perceptual target to improve discrimination. Previous research suggests that during a short time window before a saccade, covert attention is imperatively directed towards the saccade target location. Consequently, discrimination of perceptual targets at the saccade target location is better than at other locations. We asked whether the obligatory pre-saccadic attention shift prevents perceptual benefits arising for perceptual target stimuli with predictable as opposed to non-predictable properties. We compared conditions in which the color or location of the perceptual target was constant to conditions in which those properties varied randomly across trials. In addition to the expected improvements of perception at the saccade target location, we found perception to be better with constant than with random properties of the perceptual target. Thus, color or location information about an upcoming perceptual target facilitates perception even while spatial attention is shifted to the saccade target. The improvement occurred irrespective of the saccade target location, which suggests that the underlying mechanism is independent of the pre-saccadic attention shift, but alternative interpretations are discussed as well., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In a recent study, we observed that saccadic distraction (i.e., the remote distractor effect, RDE) was reduced when target and distractor were displayed at unequal contrast [Born, S., & Kerzel, D. (2008). Influence of target and distractor contrast on the remote distractor effect. Vision Research, 48(28), 2805-2816]. We hypothesized that arrival times explain the RDE modulation: With equal contrast, target and distractor signals arrive simultaneously in the oculomotor system so that mutual inhibition (and therefore saccadic distraction) is largest. With unequal contrast, high-contrast signals arrive earlier than low-contrast signals, resulting in less mutual inhibition and little saccadic distraction. In the current contribution, we presented target and distractor at different stimulus onset asynchronies (SOA) to re-align arrival times with unequal contrast. Results confirmed that unequal contrast of target and distractor reduced saccadic distraction with simultaneous presentation and that strong distraction could be reestablished by introducing a SOA. However, maximal saccadic distraction also varied strongly with the specific combination of target and distractor contrast. Thus, contrast may not only modulate arrival times of target and distractor signals, but also their strength in the mutual inhibition process. Finally, we found more saccadic distraction when the distractor was presented slightly after the target. A second experiment suggests that alerting effects superimposed on the distraction contribute to this effect, but may not fully explain it. We suggest that distraction may be strongest when the rise-to-threshold of the target-related signal has already advanced., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

In the absence of distractors, saccadic latencies are influenced by target characteristics such as contrast. The same characteristics were expected to influence the remote distractor effect (RDE) when varied in the distractor. We conducted three experiments in which we varied target and distractor contrast orthogonally. The results show that the RDE is not so much modulated by distractor contrast per se. Rather it strongly depended on the overall saccadic latencies afforded by the target: typically, shorter latencies resulted in stronger RDEs. We argue that average saccadic latencies to a target determine whether distractor-related activity temporally coincides with target-related activity. The temporal overlap is necessary for the respective neuronal signals to inhibit each other, thus evoking the RDE.