Term
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Definition
Process by which representations of stimuli interact resulting in erasure.
(occurrence of new stimuli erases the mental or neural images of old stimuli.) |
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Term
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Definition
Stimulus Onset Asynchrony:
Time in msec. between onset of a target and the onset of a mask. |
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Term
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Definition
Positive SOA:
masking where the mask occurs after presentation of a target therefore affecting the perception of the target |
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Term
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Definition
Negative SOA:
Mask occurs before the target |
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Term
Masking by Light
(Type A) |
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Definition
| Masking found in contours when extended regions of light are used as a mask. Effect strong when both target and mask are shown to the same eye instead of presents to each eye separately. |
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Term
Masking by contour
(Type B) |
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Definition
| Masking found with brightness rating or form identification. Brightness, contour detail and form are suppressed during this masking. But perception of the presence and location of target is not suppressed. |
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Term
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Definition
| Forward masking by contour |
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Term
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Definition
Backward masking by contour.
(this is much more important than paracontrast) |
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Term
Luminance Summation Contrast Reduction Hypothesis
(Eriksen's theory explaining masking of light) |
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Definition
Sensory representation of target and mask combine, resulting in decrease in contrast and visibility of the target. Max of a type A function is when target and mask occur simultaneously (SOA= 0).
Predict by Michelson ratio:
(Lmax-Lmin) /( Lmax+Lmin) |
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Term
| Masking by contour explained by neural interaction. |
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Definition
Werner suggests masking involved interruption of central contour forming mechanism.
Breitmeyer and Ganz Theory says:
presentation of visual stimulus results in quick response by magno cells followed by slower response of parvo cells. |
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