The effects of exposure duration and surrounding frames on direct and indirect tilt aftereffects and illusions

Wenderoth, Peter; Zwan, Rick van der

doi:10.3758/bf03204987

Cited by 34 publications

(19 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While increased adaptation time strengthens aftereffects, the interaction between adapting and test stimuli may not be fundamentally grounded in dynamic, adaptive processes. For example, repulsion in perceived orientation associated with the simultaneous tilt illusion (also reported by Gibson [12] closely resembles the tilt aftereffect in many respects, but does not entail adaptation [8], [32]. Furthermore, very brief presentations of an adaptor stimulus can in some cases lead to subsequent misperceptions in shape [33], [34] or orientation [35].…”

Section: Discussionmentioning

confidence: 78%

See 1 more Smart Citation

Dissociable Perceptual Effects of Visual Adaptation

et al. 2009

View full text Add to dashboard Cite

Neurons in the visual cortex are responsive to the presentation of oriented and curved line segments, which are thought to act as primitives for the visual processing of shapes and objects. Prolonged adaptation to such stimuli gives rise to two related perceptual effects: a slow change in the appearance of the adapting stimulus (perceptual drift), and the distortion of subsequently presented test stimuli (adaptational aftereffects). Here we used a psychophysical nulling technique to dissociate and quantify these two classical observations in order to examine their underlying mechanisms and their relationship to one another. In agreement with previous work, we found that during adaptation horizontal and vertical straight lines serve as attractors for perceived orientation and curvature. However, the rate of perceptual drift for different stimuli was not predictive of the corresponding aftereffect magnitudes, indicating that the two perceptual effects are governed by distinct neural processes. Finally, the rate of perceptual drift for curved line segments did not depend on the spatial scale of the stimulus, suggesting that its mechanisms lie outside strictly retinotopic processing stages. These findings provide new evidence that the visual system relies on statistically salient intrinsic reference stimuli for the processing of visual patterns, and point to perceptual drift as an experimental window for studying the mechanisms of visual perception.

show abstract

Section: Discussionmentioning

confidence: 78%

“…adapting) and probe stimuli (e.g. [8], for a review see [9]). These and other findings raise the question, to what extent are aftereffects determined by adaptation to the inspection stimulus, and to what extent are they a function of the relationship between the adapting and probe stimulus?…”

Section: Introductionmentioning

confidence: 99%

Dissociable Perceptual Effects of Visual Adaptation

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Among them, the tilt illusion exhibits a similar temporal profile to our findings. Wenderoth and Johnstone (1988), using grating stimuli, showed that the tilt illusion decreased as test duration increased up to approximately 100 ms and then leveled off (see also Wenderoth & van der Zwan, 1989). Westheimer (1990) also showed a similar temporal profile of the tilt illusion using line stimuli.…”

Section: Other Illusionsmentioning

confidence: 73%

“…The brightness change in gray central bars by brighter/darker surrounding bars was seen at surround durations as short as 58 ms and was strongest at this duration. Other illusions such as the Craik-O'Brien-Cornsweet (COC) illusion (Wachtler & Wehrhahn, 1997), tilt contrast, and tilt aftereffect with flashed tests (Wenderoth & Johnstone, 1988;Wenderoth & van der Zwan, 1989;Westheimer, 1990;Wolfe, 1984) have been found to show similar duration-dependent properties. These fast-occurring illusions have one thing in common: They are all driven by a difference between adjacent areas on a local scale.…”

Section: Introductionmentioning

confidence: 99%

Flashed stimulation produces strong simultaneous brightness and color contrast

Kaneko

Murakami

2012

Journal of Vision

View full text Add to dashboard Cite

Simultaneous brightness contrast and simultaneous color contrast are classical illusions that demonstrate how our perception can be altered by spatial context; a central gray region appears to have brightness and color that are complementary to those of a surrounding region. Previous studies have suggested the involvement of a sluggish process in these illusions. On the other hand, a different, fast mechanism has recently been postulated to operate in simultaneous contrast when the stimulus is presented only briefly. Here, we show that in briefly flashed stimuli, not only the simultaneous brightness contrast but also the simultaneous color contrast is perceived with greatly enhanced illusion strength. In simultaneous brightness contrast, inserting a spatial gap between the center and surround weakened the illusion only when the stimulus was flashed. In simultaneous color contrast, the gap weakened the illusion irrespective of stimulus duration. Both brightness contrast and color contrast effects steeply decayed with duration. The present study suggests the existence of a fast-responding process for estimating brightness/color primarily based on local difference in luminance/color along the edge between the center and surround. We argue that the sluggishness of simultaneous contrast demonstrated by previous studies originated from a sluggish process after local and fast spatial interactions.

show abstract

“…However, when the orientation difference between the target and surround is large (60°-80°), the perceived target orientation is attracted toward that of the surround, a phenomenon known as the indirect TI (8,9). The indirect TI is smaller in magnitude and has been reported to differ in several fundamental ways from the TI (e.g., it is reduced by having a frame around the stimulus, it is immune to the addition of a gap between target and surround, and it is not dependent on spatial frequency) leading to the suggestion that it results from higherlevel feedback that reflects the operation of global processing and involves a separate mechanism to the one responsible for the TI (8)(9)(10).…”

mentioning

confidence: 99%

Dynamics of unconscious contextual effects in orientation processing

Mareschal

Clifford

2012

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Contextual effects abound in the real world; how we perceive an object depends on what surrounds it. A classic example of this is the tilt illusion (TI) whereby the presence of a surround shifts the perceived orientation of a target. Surprisingly, the magnitude and direction of this shift depend on the orientation difference between the target and surround: when their orientations are similar, the perceived difference is amplified and the target appears repelled in orientation from the surround (i.e., the TI). However, when their orientations are close to perpendicular, the difference is decreased and the target appears attracted in orientation toward the surround (i.e., the indirect TI). These misperceptions of orientation have revealed much about the underlying detectors involved in visual processing and how they interact with each other. What remains at stake are the levels of processing involved. To examine this, we designed a reverse-correlation technique whereby observers are blind to the orientation of the surround. We find that the TI and indirect TI occur reliably and over a similar time course, supporting the role of a single mechanism underlying orientation biases that operates in the early stages of visual processing before the conscious extraction of the surround orientation.visual illusions | classification images | awareness C ontextual effects arise when surrounding stimuli alter our perception of a target. Understanding how and when these illusions occur is critical for elucidating the mechanisms underlying visual processing. A common example is the tilt illusion (TI) whereby the perceived orientation of a target is repelled from the orientation of the surround when the angle between them is small (1-7). However, when the orientation difference between the target and surround is large (60°-80°), the perceived target orientation is attracted toward that of the surround, a phenomenon known as the indirect TI (8, 9). The indirect TI is smaller in magnitude and has been reported to differ in several fundamental ways from the TI (e.g., it is reduced by having a frame around the stimulus, it is immune to the addition of a gap between target and surround, and it is not dependent on spatial frequency) leading to the suggestion that it results from higherlevel feedback that reflects the operation of global processing and involves a separate mechanism to the one responsible for the TI (8-10).Early models account for the TI as a normalization process toward cardinal orientations (1), or as inhibitory lateral interactions between oriented neurons in early cortical areas (refs. 3, 4, 11, but see ref. 12), but many fail to address the indirect TI. More recent models account for the indirect TI but remain agnostic as to where it occurs and whether it involves a separate processing stream from the direct TI. Clifford et al. (13) present a model whereby responses from a population of neurons with tuning properties similar to those in early cortical areas are shifted and scaled in a manner that could arise from ...

show abstract

The effects of exposure duration and surrounding frames on direct and indirect tilt aftereffects and illusions

Cited by 34 publications

References 27 publications

Dissociable Perceptual Effects of Visual Adaptation

Dissociable Perceptual Effects of Visual Adaptation

Flashed stimulation produces strong simultaneous brightness and color contrast

Dynamics of unconscious contextual effects in orientation processing

Contact Info

Product

Resources

About