What is a masking stimulus?
Masking refers to the difficulty in seeing one stimulus, the target stimulus, when it is quickly replaced by a second stimulus that occupies the same or adjacent spatial locations.
What is a post stimulus mask?
In cognitive psychology, visual backward masking involves presenting one visual stimulus (a “mask” or “masking stimulus”) immediately after a brief (usually 30 ms) “target” visual stimulus resulting in a failure to consciously perceive the first stimulus.
How does backward masking work?
A method in cognitive psychology, backward masking occurs when a visual stimulus is presented to a subject which is immediately followed by another visual stimulus which ‘masks’ the effect of the first stimulus. It is ‘masking’ the effects of one stimulus by presenting another immediately after it.
What is Metacontrast masking?
Metacontrast masking refers to the suppression of the visibility of a briefly flashed target stimulus by a similarly brief and spatially adjacent mask stimulus that follows the target in time at varying stimulus onset asynchronies (SOAs).
What is forward and backward masking?
Temporal masking refers to masking (i.e., obscuring of one sound by another) that occurs when a signal and a masker are not presented simultaneously. Backward masking occurs when the masker follows the signal; forward masking occurs when the masker precedes the signal (Fig. 18.5).
What does masking suggest about consciousness?
Visual masking has frequently been used to study the neural correlates of consciousness. Depending on conditions, masking can lead to decreases of brain activity at various stages of the visual system. But despite being invisible, masked targets can undergo a considerable degree of processing in the visual system.
What is the purpose of visual masking?
Visual masking is a phenomenon of visual perception. It occurs when the visibility of one image, called a target, is reduced by the presence of another image, called a mask. The target might be invisible or appear to have reduced contrast or lightness.
Is backward masking effective?
Several key principles of temporal masking were demonstrated in a series of classic studies by Elliott (1962), who reported that: (1) backward masking is more effective than forward masking – given the same time interval between masker and signal, more masking occurs when the masker follows the signal; and (2) masking …
What makes Metacontrast masking unique when compared to other types of masking?
Metacontrast masking uses a special type of masker and is distinguished from other types of masking in the pattern of results it generates. The target is often a small dot and the mask is an annulus that surrounds the dot. Each is presented very briefly (10-100 milliseconds).
How does visual masking work?
Why does backward masking occur?
Backward masking apparently occurs at higher centers of processing in the nervous system where the neural correlates of the later-occurring stimulus of greater intensity overtake and interfere with those of the weaker stimulus.
What is the significance of simultaneous masking?
Simultaneous masking occurs when a sound is made inaudible by a noise or unwanted sound of the same duration as the original sound. For example, a powerful spike at 1 kHz will tend to mask out a lower-level tone at 1.1 kHz. Also, two sine tones at 440 and 450 Hz can be perceived clearly when separated.