Change blindness: past, present, and future

The topic of this paper is the complex interaction between attention, fixation, and one species of change blindness. The two main interpretations of the target phenomenon are the 'blindness' interpretation and the 'inaccessibility' interpretation. These correspond to the sparse view (Dennett 1991; Tye, 2007) and the rich view (Dretske 2007; Block, 2007a, 2007b) of visual consciousness respectively. Here I focus on the debate between Fred Dretske and Michael Tye. Section 1 describes the target phenomenon and the dia-lectics it entails. Section 2 explains how attention and fixation weigh in these debates, and argues that Dretske's hyper-rich view fails precisely because he overlooks certain effects of attention and fixation. Section 3 explains why Tye's view is also unsatisfying, mainly because he misconceives the degree of access. Section 4 then puts forward the positive model covariance, which has it that the degree of cognitive access tracks the degree of phenom-enology, and contrasts it with Block's view on the Sperling iconic memory paradigm. The paper ends with a discussion of levels of seeing, which involve crowding, indexing, and other visual phenomena. Change 'blindness' is a set of phenomena that was discovered about two decades ago, yet an entirely satisfying understanding is still lacking. To move forward, a more detailed understanding of attention and fixation is called for.

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Encyclopedia of Cognitive Science

Consciousness and Cognition, 2008

Change blindness illustrates a remarkable limitation in visual processing by demonstrating that substantial changes in a visual scene can go undetected. Because these changes can ultimately be detected using top-down driven search processes, many theories assign a central role to spatial attention in overcoming change blindness. Surprisingly, it has been reported that change blindness can occur during blink-contingent changes even when observers fixate the changing location [O'Regan, J. K., Deubel, H., Clark, J. J., & Rensink, R. A. (2000). Picture changes during blinks: Looking without seeing and seeing without looking. Visual Cognition, 7, 191-212]. However, eye blinks produce a transient disruption of vision that is independent of any associated changes in the retinal image. We determined whether these 'attentive blank stares' could occur in the absence of blink-mediated visual suppression. Using a flicker change-blindness paradigm we confirm that despite direct attentive fixations, obvious scene changes often remain undetected. We conclude that change detection involves object or feature based attentional mechanisms, which can be 'misdirected' despite the allocation of spatial attention to the position of the change.

Visual Cognition, 2000

Experiments on scene perception and change blindness suggest that the visual system does not construct detailed internal models of a scene. These experiments therefore call into doubt the traditional view that vision is a process in which detailed representations of the environment must be constructed. The non-existence of such detailed representations, however, does not entail that we do not perceive the detailed environment. The "grand illusion hypothesis" that our visual world is an illusion rests on (1) a problematic "reconstructionist" conception of vision, and (2) a misconception about the character of perceptual experience.

2003

2.. Attention and storage in working memory protects against change blindness AA crucial factor in change detection seems to be attention, a phenomenon discussed in BOX 1.. In the real world, changes almost always involve motion or luminance changes. This often evokess a visual transient that is unique, or very salient with respect to background noise, so that itt attracts attention (Phillips & Singer, 1974; Rensink, 2000b, 2002). Without a blank interval in thee change blindness paradigm, the unique transient makes the change easy to detect. With the

This study examined the notion that visually fixating at a stimulus can help prevent change blindness from occurring and looks at change blindness blindness, a common metacognitive error shown by participants. 77 participants were randomly selected and assigned to different conditions. Experimental group had an extra task that they had to perform while attending to the video and the control group only had to watch the video. Participants in both conditions were required to fill out a questionnaire measuring their confidence levels to notice the change. Both conditions failed to detect changes with insignificant difference between the groups, even though the stimulus was visually fixated. Most participants overestimated their change detecting abilities, predicting in the questionnaire that they would notice the change, while in practice they did not. Thus an extra task in the experimental condition did not produce a cognitive overload leading to change blindness. Still participants failed to detect changes when the stimulus was fixated and failed to measure their change detecting abilities realistically.

British Journal of Psychology, 2006

Change blindness is often taken as evidence that visual representations are impoverished, while successful recognition of specific objects is taken as evidence that they are richly detailed. In the current experiments, participants performed cover tasks that required each object in a display to be attended. Change detection trials were unexpectedly introduced and surprise recognition tests were given for nonchanging displays. For both change detection and recognition, participants had to distinguish objects from the same basic-level category, making it likely that specific visual information had to be used for successful performance. Although recognition was above chance, incidental change detection usually remained at floor. These results help reconcile demonstrations of poor change detection with demonstrations of good memory because they suggest that the capability to store visual information in memory is not reflected by the visual system's tendency to utilize these representations for purposes of detecting unexpected changes.

Consciousness and Cognition, 2010

The goal of this study is to characterize observers' abilities to detect gradual changes and to explore putative dissociations between conscious experience of change and behavioral adaptation to a changing stimulus. We developed a new experimental paradigm in which, on each trial, participants were shown a dot pattern on the screen. Next, the pattern disappeared and participants had to reproduce it. In some conditions, the target pattern was incrementally rotated over successive trials and participants were either informed or not of this change. We analyzed both awareness of the changes and the dynamics of behavioral adaptation, in a way that makes it possible to assess both variability and accuracy as they change over time. Results indicate a dissociation between change awareness and behavioral adaptation to the changes, and support the notion that unconscious representations of visual stimuli are more precise and detailed than previously suggested. We discuss the implications of these results for theories of change detection. Crown steps of 1°of visual angle on each display, with each display separated from the next one by a brief blank screen (1500 ms). Participants were instructed to press a button if they had noticed the scene change. The results indicated that half of the participants remained unaware of the change up to a dramatic rotation of 48°. However, when a shift back to the original scene was produced after a cumulated rotation of 20°or 30°that had so far remained undetected, most subjects could then clearly see the change. Authors concluded that visual memory had been updated, albeit in the absence of awareness. Indeed, if visual memory had not been updated at all, participants would not have been able to detect the change when presented anew with the original display. These results clearly challenge the idea that change blindness arises from a failure to maintain relevant information in memory (see also, .

Cognitive Science, 2004

Change blindness provides a new technique for mapping visual attention with unprecedented spatial and temporal resolution. Change blindness can occur when a brief full‐field blank interferes with the detection of changes in a scene that occur during the blank. This interference can be overcome by attending to the location of a change. Because changes are detected at attended locations, but not at unattended locations, detection accuracy provides an indirect measure of the distribution of visual attention. The likelihood of detecting a new element in a scene provides a measure of the occurrence of attention at that element's location. Potential new directions, advantages, and problems with this method are considered.

Abstract Change blindness is a person‟ s inability to notice changes in a visual scene that seem obvious when pointed out. Recent experiments using eye tracking techniques have suggested that even though participants do not detect a change they fixate on the changing area more. Two studies test whether this finding is present across different change blindness paradigms and whether it is detectable after fixation. In the first study we compare behavior in flicker and gradual change paradigms.

Visual Cognition, 2012

The study of perception has and continues to reveal surprising results, perhaps none more so than the intricate and complex nature of perceptual awareness. The phenomenon of change blindness is no exception, this error in perceptual processing also known as "looked but failed to see" is estimated to cause around 8% of all road traffic accidents . It is thought that change blindness is due to a low memory capacity in the perceptual system . Galpin, Underwood, Crundall (2009) found semantic relevance of the stimulus and spatial position to be significant factors in change blindness.