What you see is what you need

Abstract

We studied the role of attention and task demands for implicit change detection. Subjects engaged in an object sorting task performed in a virtual reality environment, where we changed the properties of an object while the subject was manipulating it. The task assures that subjects are looking at the changed object immediately before and after the change. Our results demonstrate that in this situation subjects' ability to notice changes to the object strongly depends on momentary task demands. Surprisingly, frequent noticing is not guaranteed by task relevance of the changed object attribute per se, but the changed object attribute needs to be task relevant at exactly the right times. Also, the simplicity of the used objects indicates that change blindness occurs in situations where the visual short term memory load is minimal, suggesting a potential dissociation between short term memory limitations and change blindness. Finally, we found that changes may even go unnoticed if subjects are visually tracking the object at the moment of change. Our experiments suggest a highly purposive and task specific nature of human vision, where information extracted from the fixation point is used for certain computations only "just in time" when needed to solve the current goal.

Sources of variability in interceptive movements

“…Here again all 1058 trials without missing data are included. When performing everyday tasks our eyes are usually directed at the object or objects that are relevant for what we are doing at that moment Johansson et al 2001;Land et al 1999;Land and Hayhoe 2001;Triesch et al 2003), or toward positions at which critical information is expected to become available (e.g., information about how a ball bounces; Land and Furneaux 1997;Land and McLeod 2000). We could therefore tentatively conclude from Fig.…”

Can Selection Effects on Experience Influence its Rational Role?*

“…A similar explanation could apply to an experiment reported by Triesch et al (2003), who were investigating change-blindness in the context of a sorting task. Participants who are fixating a block while moving it (in a virtual environment) sometimes fail to report changes in height or color, even when the change is relevant to their motor task, such as moving the tall blue blocks to one place and short yellow ones to another.…”

Learning robotic eye–arm–hand coordination from human demonstration: a coupled dynamical systems approach

“…It is well established that the gaze fixation durations, together with the position of the gaze, provide a measure of cognitive processing when performing an ongoing task, being positively correlated with cognitive load required for processing visual information (Rayner 1998;Deubel et al 2000;Jacob and Karn 2003;Hayhoe and Ballard 2005;Tatler et al 2011). Gaze fixations in visually guided manipulation allow very specific task-dependent acquisition of visual information (Triesch et al 2003). This selectivity in information processing is reflected in the duration of fixations (i.e., a variability in fixation duration corresponds to a variability in visual features being selectively acquired from the early visual structures and further processed in the higher cortical structures).…”