This is Experiment 4 in the **Journal of Vision** article **Schweitzer, R., & Rolfs, M. (2020). Intra-saccadic motion streaks as cues to linking object locations across saccades**. Please note that specifications of degrees of visual angle (dva) reported here in this pre-registration are incorrect due to an observer-screen distance erroneously specified in the experimental code. For the correct values, please refer to the publication above. **Background** Whenever we make rapid eye movements, so-called saccades, the projection of the visual world shifts across our retina at very high speeds. Still, we never consciously experience any visual disturbances while we move our eyes, such as blurry, grayed-out images or smear. The absence of smear has often been attributed to a mechanism, called *saccadic suppression*. Burr & Ross (1982) proposed that “during saccades motion sensitivity is dampened, precisely to avoid the disturbing consequences of saccadic image motion which would follow if it were left intact” (p. 483), leading to the wide-spread notion that we are (motion-) blind during saccades. More recent studies suggest that *intrasaccadic motion perception* is well possible (e.g., Castet & Masson, 2000; Castet et al., 2002) and can even be quite efficient (e.g., Garcìa-Pérez & Peli, 2011; Mathôt et al., 2015). However, it is still unclear whether intrasaccadic perception has a functional role, and if so, to what processes it might contribute. In this study, we will investigate whether and how well intrasaccadic perception can be used to detect object motion occurring during saccades. **Experimental Approach** This one is an easier version of the previous experiment: [https://osf.io/7apa8/][1]. This time, one the active saccade condition will be tested. Like in the previous experiment DIDO3, participants are tasked to make a horizontal saccade (16 dva) towards a Gabor patch of varying spatial frequency (0.5, 1, or 2 cycles/dva) and orientation (0, 45, 90, and 135 deg (counterclockwise from vertical that is 0). While the saccade is in mid-flight this Gabor patch (target stimulus) moves vertically either upwards or downwards. The target moves across a distance of 8 dva at a speed of approximately 360 dva/s (movement duration ~22ms). At the end of each movement, a second but similar Gabor patch (distractor stimulus) will be displayed at a position opposite to the final position of the target. After saccade completion, the participants' task is to indicate whether the target stimulus moved upwards or downwards. If participants are able to process brief intrasaccadic motion signals, they will be able to differentiate between contingent and apparent stimulus movements of target stimulus and distractor stimulus, respectively. The differences to summed up: - twice the distance traveled: 8 dva instead of 4 dva at the same speed. - contrast 100% instead of 50% - an improved version of saccade detection using a moving window smoothing with a span of 5 Altogether, these changes aim at improving overall performance in the task. **References** Burr, D. C., & Ross, J. (1982). Contrast sensitivity at high velocities. *Vision Research*, 22(4), 479–484. Castet, E., Jeanjean, S., & Masson, G. S. (2002). Motion perception of saccade-induced retinal translation. *Proceedings of the National Academy of Sciences*, 99(23), 15159–15163. Castet, E., & Masson, G. S. (2000, February). Motion perception during saccadic eye movements. *Nature Neuroscience*, 3(2), 177–183. Garcìa-Pérez, M. A., & Peli, E. (2011). Visual contrast processing is largely unaltered during saccades. *Frontiers in Psychology*, 2, –. Mathôt, S., Melmi, J., & Castet, E. (2015). Intrasaccadic perception triggers pupillary constriction. *PeerJ,* 3, e1150. [1]: https://osf.io/7apa8/