Temporal 2 - Successive Contrast

What is simultaneous contrast?

A phenomenon in which perception of a color is altered by the colors surrounding it.

How localized is simultaneous contrast compared with color constancy?

It is more localized than color constancy.

In simultaneous contrast, a color tends to shift toward what hue of its background?

The complementary hue of its background.

How does simultaneous contrast affect figure-ground borders?

It enhances figure-ground borders.

What are the three color features involved in simultaneous contrast?

Hue, value (lightness), and saturation.

What aspect of brightness perception is simultaneous contrast similar to?

Mach bands.

How does simultaneous contrast differ from Mach bands?

It occurs across a whole uniform area rather than only at edges.

What is successive contrast?

The temporal counterpart to simultaneous contrast in which perception of a new stimulus is influenced by a previous stimulus.

What is another name for successive contrast?

An aftereffect.

What mechanisms produce successive contrast?

Adaptation, fatigue, and rebound, especially in opponent systems.

Are successive contrast effects usually attractive or repulsive?

Usually repulsive.

When can successive contrast effects become attractive?

On very short time scales during stimulus prediction.

Are successive contrast effects long-lasting?

No, they are short-lived.

What is a common example of successive contrast?

Color adaptation.

What happens after viewing a color stimulus for an extended period and then looking at a white field?

Complementary colors are perceived as an aftereffect.

What demonstrates successive color contrast?

Viewing a color wheel for approximately 20 seconds and then looking at a white or red field.

What is the tilt aftereffect?

A change in perceived orientation caused by prior adaptation to an oriented stimulus.

What feature of the adapting stimulus determines the strength of the tilt aftereffect?

The orientation difference between adapting and test stimuli.

Where is the tilt aftereffect strongest?

At the same retinal location as the adapting stimulus.

Does the tilt aftereffect occur when stimuli differ in color?

Yes.

Does the tilt aftereffect occur when stimuli differ in luminance?

Yes.

Does the tilt aftereffect occur when stimuli differ in contrast?

Yes.

Does the tilt aftereffect occur when stimuli differ in disparity depth?

Yes.

Does the tilt aftereffect occur when stimuli differ in temporal separation?

Yes.

Does the tilt aftereffect occur when stimuli differ in spatial frequency?

Yes.

How does spatial frequency difference affect the tilt aftereffect?

The effect weakens as the spatial frequency difference increases.

Can the tilt aftereffect occur dichoptically?

Yes.

What was the task in studies of adaptation to mean tilt?

To decide whether the mean orientation of a test array was clockwise or counterclockwise relative to a vertical reference.

How does variance adaptation affect orientation judgments?

Variance adaptation influences mean orientation discrimination sensitivity.

What is adaptation to mean tilt?

An adaptation effect in which exposure to orientation variance alters sensitivity to mean orientation.

What was the task in studies of adaptation to tilt variance?

To decide which array had more heterogeneous orientations.

How does mean orientation adaptation affect variance judgments?

Mean orientation adaptation influences orientation variance discrimination sensitivity.

What is adaptation to tilt variance?

An adaptation effect in which orientation adaptation alters discrimination of orientation variability.

What is speed adaptation?

A perceptual aftereffect produced by prolonged exposure to motion at a particular speed.

How does adaptation affect perception of the adapted speed?

The adapted speed appears slower.

How does speed adaptation affect perception of other speeds?

It repulses perception of other speeds away from the adapted speed.

How does adaptation duration affect speed adaptation?

Longer adaptation durations increase repulsion strength.

What is size adaptation?

A perceptual aftereffect in which prior exposure to a stimulus alters perceived size of subsequent stimuli.

After adapting to a larger stimulus, how does a test stimulus appear?

It appears smaller.

What type of effect is produced when adapting to a larger size?

Repulsion.

After adapting to a smaller stimulus, how does a test stimulus appear?

It appears larger.

Is the effect of adaptation to a smaller size as strong as adaptation to a larger size?

No, it is weaker.

How does contrast difference between adapting and test stimuli affect size adaptation?

It weakens the adaptation effect.

What type of stimulus can eliminate contrast adaptation during size adaptation experiments?

Cornsweet stimuli.

What is number adaptation?

An adaptation effect in which exposure to a particular numerosity alters subsequent perception of number.

How is number adaptation typically measured?

By determining the number needed in a test stimulus to match an unadapted probe.

What is causal adaptation?

An adaptation effect that alters perception of causal interactions between moving objects.

In causal adaptation experiments, what does less overlap between two moving objects suggest?

Object 1 launches object 2, creating a causal impression.

In causal adaptation experiments, what does more overlap between two moving objects suggest?

Object 1 passes through object 2.

What does a launch event represent in causal adaptation?

A perception that one object causes another object to move.

What does a pass-through event represent in causal adaptation?

A perception that one object moves through another without causing motion.

What does PSE stand for in causal adaptation studies?

Point of Subjective Equality.

What is the PSE in causal adaptation?

The amount of overlap at which observers report launch and pass-through perceptions equally often (50/50).

What is body size adaptation?

A perceptual aftereffect in which exposure to different body widths alters perceived body size.

How were body size adaptation experiments conducted in the cited study?

Using images of the subjects themselves.

What was plotted in the body size adaptation study?

The shift in actual self-width estimation after adaptation.

How stable is adaptation to a wide body image over time?

It remains stable with time.

How does adaptation to a narrow body image change over time?

It is initially strong but weakens with time.

How did the authors interpret body size adaptation results?

As an attractive shift in perceived self-width.

What alternative explanation was proposed for body size adaptation results?

A repulsive shift in perceived test stimulus width.

What percentage measure was plotted in body size adaptation studies?

The percentage of a feature needed for neutral perception.

What is face adaptation?

A perceptual aftereffect in which exposure to a particular facial attribute biases perception of later faces.

How does adaptation to male faces affect perception of neutral faces?

Previously neutral faces appear more female.

What facial attribute can show adaptation effects involving gender?

Gender.

What facial attribute can show adaptation effects involving race?

Race.

What facial attribute can show adaptation effects involving expression?

Expression.

What expression continuum was used in face adaptation studies?

Fear–contempt.

What expression continuum was used in face adaptation studies involving positive and negative emotion?

Happy–angry.

What expression continuum was used in face adaptation studies involving surprise?

Disgust–surprise.

What is visual masking?

A phenomenon in which a visible target stimulus is eliminated or reduced in visibility by a nearby mask in time.

How does a mask affect a target stimulus?

It suppresses processing of the target.

At what level does masking typically occur?

At a high processing level even though the target is encoded at lower levels.

Can visual masking occur dichoptically?

Yes.

What is a forward mask?

A mask that precedes the target stimulus.

What is a backward mask?

A mask that follows the target stimulus.

What is a simultaneous mask?

A mask that appears at the same time as the target stimulus.

What does SOA stand for?

Stimulus Onset Asynchrony.

What is a pattern mask?

A mask that covers the target with distracting features.

What is a metacontrast mask?

A mask that perfectly outlines the target's contours.

What factors influence difficulty in backward metacontrast masking?

Contour separation, SOA, and target duration.

How does contour separation affect backward metacontrast masking?

Greater contour separation makes masking easier to overcome.

How does target duration affect backward metacontrast masking?

Target duration influences visibility and masking strength.

How does SOA affect backward metacontrast masking?

SOA strongly influences masking effectiveness.

What is integration masking?

A form of masking in which target and mask are summed temporally.

At what SOA is integration masking strongest?

SOA of 0 ms.

How does integration masking change with increasing SOA?

It falls off by approximately ±100 ms.

At what processing levels does integration masking occur?

Lower processing levels.

How does mask contrast affect integration masking?

Strength increases with mask contrast.

What is interruption masking?

A form of backward masking in which processing of the target is disrupted by the mask.

What is the primary mechanism of interruption masking?

Disruption of target processing after target presentation.

How does mask intensity affect pattern masking?

Greater mask intensity generally increases masking strength.

What is metacontrast masking?

A form of masking in which contour signals from a mask suppress perception of a target.

Does metacontrast masking have an optimal SOA?

Yes.

What mechanism is proposed for metacontrast masking?

Fast-acting mask contour signals suppress sustained target signals.

How does contour separation affect metacontrast masking?

Greater contour separation strongly reduces masking.

What is saccadic suppression?

A reduction in visual sensitivity during saccadic eye movements.

What is another name for saccadic suppression?

Saccadic masking.

Why is visual input problematic during saccades?

The visual world changes rapidly, producing retinal blur.

What signal has traditionally been proposed to suppress vision during saccades?

A visuomotor efferent copy signal.

Can sensory signals alone explain saccadic suppression?

Yes, evidence suggests they can.