The capacity of trans-saccadic memory in visual search.

Abstract

Maintaining a continuous, stable perception of the visual world relies on the ability to integrate information from previous fixations with the current one. An essential component of this integration is trans-saccadic memory (TSM), memory for information across saccades. TSM capacity may play a limiting role in tasks requiring efficient trans-saccadic integration, such as multiple-fixation visual search tasks. We estimated TSM capacity and investigated its relationship to visual short-term memory (VSTM) using two visual search tasks, one in which participants maintained fixation while saccades were simulated and another where participants made a sequence of actual saccades. We derived a memory-limited ideal observer model to estimate lower-bounds on memory capacities from human search performance. Analysis of the single-fixation search task resulted in capacity estimates (4-8 bits) consistent with those reported for traditional VSTM tasks. However, analysis of the multiple-fixation search task resulted in capacity estimates (15-32 bits) significantly larger than those measured for VSTM. Our results suggest that TSM plays an important role in visual search tasks, that the effective capacity of TSM is greater than or equal to that of VSTM, and that the TSM capacity of human observers significantly limits performance in multiple-fixation visual search tasks. (PsycINFO Database Record

Processing spatial configurations in visuospatial working memory is influenced by shifts of overt visual attention

“…While it is up to future research to identify the specific process underlying this increase in configurational processing, we speculate that processes related to trans-saccadic memory (TSM) and its interplay with VSWM might be involved. Based on TSM, observers establish correspondence between pre-saccadic and post-saccadic information, and TSM capacity is larger than or equal to VSWM capacity [ 35 ]. Therefore, it seems possible that TSM draws on inter-object relations such as spatial configurations, thereby also informing VSWM representations.…”

Perceptual Pluralism

“…Block insists that transsaccadic memory is simply VWM, and there is indeed significant experimental evidence in favor of this claim (e.g., Schut et al. 2017b; Kleene & Michel 2018). These two assumptions together entail that transsaccadic memory is cognitive rather than perceptual (Block ms.).…”

“…One might make a blanket assumption that all working memory systems, including VWM, fall cleanly within the borders of cognition rather than perception. Block insists that transsaccadic memory is simply VWM, and there is indeed significant experimental evidence in favor of this claim (e.g., Schut et al 2017b;Kleene & Michel 2018). These two assumptions together entail that transsaccadic memory is cognitive rather than perceptual (Block ms.).…”

Natural image clutter degrades overt search performance independently of set size

“…Synthetic stimuli provide researchers with a great deal of flexibility and control, enabling them to manipulate individual stimulus features and to determine how these contribute to performance in a variety of tasks. In visual search, for example, measuring performance in synthetic search displays has allowed researchers to discover how observers use information about peripheral target visibility to select fixations (Geisler, Perry, & Najemnik, 2006;Najemnik & Geisler, 2005;Najemnik & Geisler, 2008;Michel & Geisler, 2009;Verghese, 2012;Zhang & Eckstein, 2010), how intrinsic position uncertainty and clutter in the periphery degrade performance (Michel & Geisler, 2011;Rosenholtz, Huang, Raj, Balas, & Ilie, 2012;Semizer & Michel, 2017), how the template for known search targets is structured (Eckstein, Beutter, Pham, Shimozaki, & Stone, 2007), and how observers integrate information about the target across fixations (Caspi, Beutter, & Eckstein, 2004;Kleene & Michel, 2018), all while controlling extraneous properties of the search display (e.g., spectral spatial frequency statistics, environmental contingencies, target location probabilities, etc.) in ways that would be difficult or impossible with natural scenes.…”