Serial dependence is absent at the time of perception but increases in visual working memory

Abstract

Recent experiments have shown that visual cognition blends current input with that from the recent past to guide ongoing decision making. This serial dependence appears to exploit the temporal autocorrelation normally present in visual scenes to promote perceptual stability. While this benefit has been assumed, evidence that serial dependence directly alters stimulus perception has been limited. In the present study, we parametrically vary the delay between stimulus and response in a spatial delayed response task to explore the trajectory of serial dependence from the moment of perception into post-perceptual visual working memory. We find that behavioral responses made immediately after viewing a stimulus show evidence of adaptation, but not attractive serial dependence. Only as the memory period lengthens is a blending of past and present information apparent in behavior, reaching its maximum with a delay of six seconds. These results dovetail with other recent findings to bolster the interpretation that serial dependence is a phenomenon of mnemonic rather than perceptual processes. However, even while this pattern of effects in group-averaged data has now been found consistently, we show that the relative strengths of adaptation and serial dependence vary widely across individuals. Finally, we demonstrate that when leading mathematical models of working memory are adjusted to account for these trial-history effects, their fit to behavioral data is substantially improved.

The role of feature-based attention in visual serial dependence

“…Next to positive attraction biases for subsequent stimuli with similar orientations, we expected to observe negative repulsive biases for stimuli with large orientation differences beyond 60° (Bliss et al;Fritsche et al, 2017). In order to test whether such repulsive biases also occurred in the current experiment, we averaged each participant's adjustment response errors in a negative and positive bin.…”

“…Besides attractive serial dependence biases, previous studies have observed concurrent repulsive biases when subsequent stimuli differed markedly (Fritsche et al, 2017;Bliss et al, 2017). Currently, it is unclear whether attractive and repulsive biases originate from the same underlying neural process, or whether these are two distinct phenomena, concurrently observed in behavioral responses.…”

“…In line with this idea, recent studies have found that perceptual decisions about a large variety of visual stimulus features are biased towards features encountered in the recent past. Such features include orientation (Cicchini & Burr, 2017;Czoschke, Fischer, Beitner, Kaiser, & Bledowski, 2018;Fritsche et al, 2017), numerosity (Cicchini, Anobile, & Burr, 2014;Corbett, Fischer, & Whitney, 2011;Fornaciai & Park, 2018a), spatial location (Bliss, Sun, & D'Esposito, 2017;Manassi, Liberman, Kosovicheva, Zhang, & Whitney, 2018;Papadimitriou, White, & Snyder, 2016), visual variance (Suárez-Pinilla, Seth, & Roseboom, 2018), face identity (Liberman, Fischer, & Whitney, 2014), emotional expression and attractiveness (Xia, Leib, & Whitney, 2016). While it is still debated whether such serial dependence biases are introduced at a perceptual stage or at a post-perceptual, decision or short-term memory stage (Fritsche et al, 2017;Bliss et al, 2017;Cicchini & Burr, 2017;Fornaciai & Park, 2018a), the ubiquity of serial dependencies in perceptual decisions is striking and suggests that serial dependencies might arise from a general computation of the brain, potentially reflecting the stabilization of neural representations.…”

Reference Repulsion Is Not a Perceptual Illusion

“…http://dx.doi.org/10.1101/366393 doi: bioRxiv preprint first posted online Jul. 10, 2018; 2018; Bliss et al, 2017;Fritsche et al, 2017;Papadimitriou et al 2015). Furthermore, the postperceptual nature of this repulsive bias away from an external reference delineates the effect from repulsive perceptual biases away from cardinal orientations, which may act as internal references (Rauber & Treue, 1998;Tomassini, Morgan & Solomon, 2010;Wei & Stocker, 2015).…”

“…Importantly, some of these contextual biases measured in participants' responses arise early during visual processing, for instance during the encoding of the physical stimulus or decoding of the sensory representation (Webster, 2015), whereas others arise at later post-perceptual decisional stages (Firestone & Scholl, 2016;Fritsche, Mostert, & de Lange, 2017), during working memory retention (Bliss, Sun & D'Esposito, 2017;Huang & Sekuler, 2010;Papadimitriou, Ferdoash & Snyder, 2015; Visscher, Kahana, & Sekuler, 2009) or when a motor response is formed (Pape & Siegel, 2016).…”