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Real-world scenes elicit anticipatory representation in long-term memory (LTM) and working memory (WM) resulting in boundary extension (BE). Would the same results hold for nonscene patterns of objects? In Experiment 1A (LTM-paradigm), 15 regular or 15 random object-patterns were sequentially presented (10 s each); a boundary-rating-task followed. Both pattern-types elicited BE. Surprisingly, regularity (greater pattern predictability) did not enhance BE. Instead, random patterns more consistently yielded BE. Perhaps random object-groupings enhance BE (e.g., more scene-like). Objects within regular patterns were colored to create object-groupings; this increased BE compared to regular patterns without color groups, but only in 1 of the 2 tests (Experiment 1B, LTM-paradigm). In Experiment 2 (WM-paradigm), a briefly presented pattern, regular or random, was followed by a 2-s masked interval and a boundary-rating-task on each trial. Here, results reversed: patterns now elicited boundary restriction (whether or not a concurrent task had been presented to prevent verbalization). Under time pressure, without real-world layout and meaning, pattern elements may not have cohered into a unified expanse, failing to elicit BE and resulting in loss of peripheral content. We propose 2 classes of visual content that may determine anticipatory representation: content that embellishes space versus content that defines space. Public Significance Statement: When viewing real-world scenes, the brain anticipates surrounding layout; this study showed that novel patterns also elicited anticipatory representation given sufficient time, but not when the same patterns were briefly presented. Not only was anticipatory processing halted, but also participants lost memory for the peripheral elements of the patterns. This demonstrates the critical role of top-down knowledge and expectations in supporting anticipatory representation, which may be crucial for a moving observer's successful interaction with the surrounding world. [ABSTRACT FROM AUTHOR]

The ability to navigate without getting lost is an important aspect of quality of life. In 5 studies, we evaluated how spatial learning is affected by the increased demands of keeping oneself safe while walking with degraded vision (mobility monitoring). We proposed that safe low vision mobility requires attentional resources, providing competition for those needed to learn a new environment. In Experiments 1 and 2, participants navigated along paths in a real-world indoor environment with simulated degraded vision or normal vision. Memory for object locations seen along the paths was better with normal compared with degraded vision. With degraded vision, memory was better when participants were guided by an experimenter (low monitoring demands) versus unguided (high monitoring demands). In Experiments 3 and 4, participants walked while performing an auditory task. Auditory task performance was superior with nonnal compared with degraded vision. With degraded vision, auditory task performance was better when guided compared with unguided. In Experiment 5, participants performed both the spatial learning and auditory tasks under degraded vision. Results showed that attention mediates the relationship between mobility-monitoring demands and spatial learning. These studies suggest that more attention is required and spatial learning is impaired when navigating with degraded viewing. [ABSTRACT FROM AUTHOR]

The Simon effect refers to the relatively poorer response times and accuracy when responding to targets that appear in a task-irrelevant spatial location that is incongruent with the location of the correct response key, compared with targets that appear in spatially congruent locations. Like Stroop and flanker effects, the Simon effect is thought to result from conflict between an irrelevant response tendency and an intended response. Because attentional control has been linked to conflict resolution, the Simon task has been proffered as a possible tool for measuring the efficacy of executive control mechanisms. These mechanisms are also involved in working memory (WM) processes, and are thought to be responsible for maintaining information in the presence of continued processing or distraction. The present study investigated the interface between WM and attention by examining the time course of the Simon effect over the response time distributions under varying WM load conditions. Participants completed verbal 0-back, spatial 0-back, verbal 2-back, and spatial 2-back tasks. Results show that the Simon effect is diminished in high WM load tasks compared with low-load tasks, and that the Simon effect interacts with the spatial task domain such that the effect persists across the distribution of response times. In contrast, the Simon effect peaks and decays in verbal tasks. The results demonstrate that the Simon effect interacts with WM load and task domain. The results suggest that the effect is more modifiable than expected, and support a complex interface between WM and attentional control. [ABSTRACT FROM AUTHOR]