Color onsets and offsets, and luminance changes can cause change blindness (original) (raw)

Perceptual conditions necessary to induce change blindness

Visual Cognition 10(2):233-255, 2003

Change blindness is a failure to detect a change in an scene when the change occurs along with some visual disturbances. Disturbances are thought to play a delocalizing role that affects the saliency of the “target” transient signal coming from the change location, which would otherwise capture attention and render the change visible. For instance, it is hypothesized that the appearance of new objects in the “mudsplashes” paradigm generates transient signals that compete with the target object's transient signal for attracting attention. Thus, experiments using the mudsplashes paradigm do not rule out a possible role of object changes in capturing attention. Here, by reversing image contrast polarity, we develop a new paradigm to produce change blindness when a real global transient signal is the only visual event occurring, with no edges added or deleted except in the target object. The results show that transient signals, per se, are able to prevent change detection. However, abrupt transients are not necessary if object change occurs in the zero-contrast phase of a smoothly fading and reappearing image, leaving attention as the only common factor affecting all cases of change blindness.

Change Detection in a Change Blindness Flicker Paradigm

South African Journal of Psychology, 2004

This study explored trends in change detection within the change blindness (CB) flicker paradigm. A sample comprising 92 university students was tested for speed in change detection. A number of alternating photographic scenes with and without changes in objects were shown in a computer laboratory. There were significant differences between males and females for central and marginal interest changes on different change types, which included changes in colour, presence and location of objects. The results were used to illustrate the methodological restrictions of previous studies and to expand on theoretical explanations for this phenomenon. This study also challenged the various notions pertaining to the nature of the representations one forms when perceiving visually. The application of connectionist principles revealed the ambiguity of representational-based explanations for change detection.

Visual transients without feature changes are sufficient for the percept of a change

Vision Research, 2004

A visual transient due to a sudden visual change is generally considered to draw our attention to a location of interest. In a series of experiments we investigated how visual transients facilitate change detection in a scene. In line with earlier reports, we found that a transient sensation has its roots in a temporal interaction at a monocular processing level. Interestingly, we also show that visual transients make it possible to detect a change in the eye of origin, despite the fact that observers have no clue as to which eye is stimulated. That is, visual transients are detected even when there is no perceptual change in the visual content after binocular fusion. More importantly, we show that observers cannot distinguish the transient due to a change in eye of origin from a feature change (the orientation of a Gabor). Both are perceived as actual changes. We conclude that a transient signal is sufficient for the visual system to judge whether something has changed over time.

Change detection in the flicker paradigm: Do faces have an advantage?

Visual Cognition, 2003

Changes to a scene that occur during an eye movement, image flicker or movie cut are difficult to detect. One way to measure change detection performance is with the flicker paradigm, where changes between two images are introduced during a brief blank screen, which causes the images to "flicker". Ro, Russell, and Lavie (2001) presented flickering displays consisting of one face and five different common objects. They found that changes to faces were detected both more rapidly and more accurately than changes to objects and suggested that faces capture attention due to their biological significance. In the present studies, we found that changes to objects were more readily detected than changes to faces when displays consisted of an object among a number of faces. That is, a change detection advantage was observed for the "odd-one-out" in the array, regardless of its significance. Therefore, faces may not have a special status for change detection.

Changing faces: A detection advantage in the flicker paradigm

2001

Abstract Observers seem surprisingly poor at detecting changes in images following a large transient or flicker. In this study, we compared this change blindness phenomenon between human faces and other common objects (eg, clothes). We found that changes were detected far more rapidly and accurately in faces than in other objects.

Perceptual alternation induced by visual transients

Perception, 2005

When our visual system is confronted with ambiguous stimuli, the perceptual interpretation spontaneously alternates between the competing incompatible interpretations. The timing of such perceptual alternations is highly stochastic and the underlying neural mechanisms are poorly understood. Here, we show that perceptual alternations can be triggered by a transient stimulus presented nearby. The induction was tested for four types of bistable stimuli: structure-from-motion, binocular rivalry, Necker cube, and ambiguous apparent motion. While underlying mechanisms may vary among them, a transient flash induced time-locked perceptual alternations in all cases. The effect showed a clear dependency on the adaptation to the dominant percept prior to the presentation of a flash. These perceptual alternations show many similarities to perceptual disappearances induced by transient stimuli (Kanai & Kamitani, 2003, Moradi & Shimojo, 2004). Mechanisms linking these two transient induced phenomena are discussed.

Detectability of onsets versus offsets in the change detection paradigm

Journal of Vision, 2003

The human visual system is particularly sensitive to abrupt onset of new objects that appear in the visual field. Onsets have been shown to capture attention even when other transients simultaneously occur. This has led some authors to argue for the special role that object onset plays in attentional capture. However, evidence from the change detection paradigm appears contradictory to such findings. Studies of change blindness demonstrate that the onset of new objects can often go unnoticed. Assessing the relative detectability of onsets compared with other visual transients in a change detection procedure may help resolve this contradiction. We report the results of four experiments investigating the efficacy with which onsets capture attention compared with offsets. In Experiment 1, we employed a standard flicker procedure and assessed whether participants were more likely to detect the change following a frame containing an onset or following a frame containing an offset. In Experiment 2, we employed the one-shot method and investigated whether participants detected more onsets or offsets. Experiment 3 used the same method but assessed whether onsets would be detected more rapidly than offsets. In Experiment 4, we investigated whether the effect obtained in Experiments 1-3 using simple shapes would replicate when images of real-world objects were used. Results showed that onsets were less susceptible to change blindness than were offsets. We argue that the preservation of information is greater in onsets than in offsets.