Visual working memory representations in visual and parietal cortex do not remap after eye movements

Abstract

10 11 Highlights 12 • Visual working memory (VWM) representations do not remap after making 13 saccades 14 • Eye movement degrade VWM representations in early visual cortex, limiting 15 the role of early visual cortex in VWM storage 16 • Parietal cortex shows persistent VWM representations across saccades 17 2 ABSTRACT 18It has been suggested that our visual system does not only process stimuli that are 19 directly available to our eyes, but also has a role in maintaining information in VWM 20 over a period of seconds. It remains unclear however what happens to VWM 21 representations in the visual system when we make saccades. Here, we tested the 22 showed persistent VWM representations in both the saccade and no-saccade 33 condition. Together, our results indicate that VWM representations in early visual 34 cortex are not remapped across eye movements, potentially limiting the role of early 35 visual cortex in VWM storage. 36 37 Keywords: visual working memory; eye movements; fMRI; remapping; MVPA 38 109 Stimuli 110Stimuli were programmed in MATLAB (v2016a, The MathWorks, Inc., Natick, MA) 111 using the Psychtoolbox (Brainard 1997). The circular sinusoidal grating stimulus 112 6 subtended 10° and was centered with a small jitter (0.3°) on the screen center. The 113 grating was full contrast, with a spatial frequency of 1 cycles/degree, a random 114 phase and an orientation of either 25° or 115° (with a small jitter of 3°) from the 115 horizontal axis. The contrasts of the edges of the grating were linearly attenuated 116 over the distance from 4.5° to 5.0° radius. Two filled dots (0.5°, one green, one 117 black) were presented at the periphery of the screen (6° left or right away from the 118 center of the screen), which were served as the fixation dot and saccade target in 119 the task. In the behavioral training session, stimuli were presented on a 24-inch flat-120 panel display (BenQ XL2420T, 1,920 x 1,080 resolution, 60 Hz refresh rate). In the 121 fMRI sessions, stimuli were displayed on a rear-projection screen using an EIKI LC-122 XL100L (EIKI, Rancho Santa Margarita, CA) multimedia projector (1,024 x 768 123 resolution, 60 Hz refresh rate). 124 Experimental design 125Behavioral training procedure.Prior to the fMRI scan sessions, all participants 126 completed a one-hour behavioral training session to familiarize themselves with the 127 fMRI main task and to establish their individual orientation discrimination threshold, 128 which served as an initial orientation difference of the gratings in the following fMRI 129 sessions. The experimental design of the behavioral training task was exactly the 130 same as during the fMRI main task, except that the delay period and the inter-trial 131 interval (ITI) were shortened to 3 s to reduce the experimental time. Participants 132 completed two to three blocks of 56 trials until a stable orientation discrimination 133 threshold was obtained, during which the eye movements were continuously 134 monitored by an Eyelink 1000 plus eye tracker. In addition, participant...

Jointly looking to the past and the future in visual working memory

“…First, memory contents could have directly been remapped (cf. 3,[15][16][17] ) to their future-relevant location (in which case we should have only found a future gaze bias). Second, when dealing with multiple memory contents, contents could be stored at the past location at first and the future location could be considered only after relevant memory content has been selected (in which case the past bias should have preceded the future bias).…”

Low-Level Visual Information Is Maintained across Saccades, Allowing for a Postsaccadic Handoff between Visual Areas

“…We found that, even under stable fixation, SF information became less retinotopically specific over time, from ∼150 ms after stimulus onset, leading to “emerging nonretinotopy” ( Melcher and Morrone, 2015 ). This suggest that, in addition to “retinotopically lingering attention” ( Golomb et al, 2010 ), emerging nonretinotopy of feature information could allow presaccadic and postsaccadic information to be combined and support trans-saccadic perception without requiring predictive remapping in early visual processing areas ( Irwin, 1992 ; He et al, 2019 ), since higher brain areas could read out the SF of the stimulus during the entire interval. Combined with the availability of gaze position information in early visual areas ( Morris and Krekelberg, 2019 ), low-level visual information could, in theory, be read out in head-centered coordinates continuously across a saccade ( Andersen et al, 1985 ; Pouget and Sejnowski, 1997 ).…”

Saccades reset the priority of visual information to access awareness

“…However, despite these findings, there are also several studies that reported an absence of spatiotopic effects (Knapen et al, 2009, Mathôt & Theeuwes, 2010He, Ekman, & A., & de Lange, F, , 2019;Lescroart, Kanwisher, & Golomb, 2016). Together, these different sets of findings argue against a version of spatiotopic processing that is omnipresent in visual perception across saccades.…”