Attention modulates trans-saccadic integration

Abstract

With every saccade, humans must reconcile the low resolution peripheral information available before a saccade, with the high resolution foveal information acquired after the saccade. While research has shown that we are able to integrate peripheral and foveal vision in a near-optimal manner, it is still unclear which mechanisms may underpin this important perceptual process. One potential mechanism that may moderate this integration process is visual attention. Pre-saccadic attention is a well documented phenomenon, whereby visual attention shifts to the location of an upcoming saccade before the saccade is executed. While it plays an important role in other peri-saccadic processes such as predictive remapping, the role of attention in the integration process is as yet unknown. This study aimed to determine whether the presentation of an attentional distractor during a saccade impaired trans-saccadic integration, and to measure the time-course of this impairment. Results showed that presenting an attentional distractor impaired integration performance both before saccade onset, and during the saccade, in selected subjects who showed integration in the absence of a distractor. This suggests that visual attention may be a mechanism that facilitates trans-saccadic integration.

Feature integration is unaffected by saccade landing point, even when saccades land outside of the range of regular oculomotor variance

“…The authors conclude that attention may be a mechanism which facilitates or allows for transsaccadic feature integration. The critical difference with our study and the Stewart and Schütz (2018) study is that the distractor was presented at an unpredictable moment, thus involuntarily redirecting attentional resources to the distractor. In our experiment, it is likely that attentional resources are distributed across the target and distractor, and not necessarily redirected away from the saccade target.…”

“…This may be especially useful when visual information needs to be sampled specifically at the intended saccade landing point, rather than the actual saccade landing point. In line with this proposed mechanism, one notable study has found that by redirecting attention by presenting a salient presaccadic distractor, both saccade motor performance and integration of pre-and postsaccadic feature information was impaired (Stewart & Schütz, 2018). The authors conclude that attention may be a mechanism which facilitates or allows for transsaccadic feature integration.…”

Transsaccadic perception is affected by saccade landing point deviations after saccadic adaptation

“…This mislocalization could also result in a decrease of the influence on the presaccadic color. However, given the known role of visual attention in transsaccadic perception (e.g., Stewart & Schütz, 2018a ), we think our findings reflect modulations of hue perception by a change in the locus of presaccadic attention. Due to the presaccadic shift of attention, the presaccadically acquired information can be temporarily stored in visual working memory, allowing for quick transsaccadic integration after the saccade ( Schut, Van der Stoep, Postma, & Van der Stigchel, 2017 ; Steward & Schütz, 2018b ).…”

“…The notion that visual attention may be one of the crucial mechanisms driving transsaccadic perception was recently supported by Stewart and Schütz (2018a) . In their study, a salient distractor was presented at variable intervals before the execution of a saccade.…”

“…We explained this finding by the idea that the presaccadic deployment of visual attention is not affected by the actual execution of a saccade, but driven by the active oculomotor programs before saccade execution ( Van der Stigchel & de Vries, 2015 ): although the actual landing position of the saccade might be altered, the presaccadic shift of attention is allocated to the intended saccade target location ( Deubel & Schneider, 1996 ). Because transsaccadic feature integration is a mechanism that is mainly dependent upon visual spatial attention ( Steward & Schütz, 2018a ; Van der Stigchel & Hollingworth, 2018 ), it should be robust against variance in saccade landing point in situations in which the locus of the presaccadic deployment of attention is unaffected. In such cases, the weights attributed to the presaccadic and postsaccadic information should remain the same despite the fact that saccadic landing points deviate from the intended target location.…”