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Temporal processes in prime-mask interaction: Assessing perceptual consequences of masked information.

Scharlau I - Adv Cogn Psychol (2008)

Bottom Line: These models predict that the perceptual latency of a visual backward mask is shorter than that of a like reference stimulus that was not preceded by a masked stimulus.The prediction has been confirmed by studies using temporal-order judgments: For certain asynchronies between mask and reference stimulus, temporal-order reversals are quite frequent (e.g. Scharlau, & Neumann, 2003a).Consequences for theories of visual masking such as asynchronous-updating, perceptual-retouch, and reentrant models are discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Bielefeld University, Germany.

ABSTRACT
Visual backward masking is frequently used to study the temporal dynamics of visual perception. These dynamics may include the temporal features of conscious percepts, as suggested, for instance, by the asynchronous-updating model (Neumann, 1982) and perceptual-retouch theory ((Bachmann, 1994). These models predict that the perceptual latency of a visual backward mask is shorter than that of a like reference stimulus that was not preceded by a masked stimulus. The prediction has been confirmed by studies using temporal-order judgments: For certain asynchronies between mask and reference stimulus, temporal-order reversals are quite frequent (e.g. Scharlau, & Neumann, 2003a). However, it may be argued that these reversals were due to a response bias in favour of the mask rather than true temporal-perceptual effects. I introduce two measures for assessing latency effects that (1) are not prone to such a response bias, (2) allow to quantify the latency gain, and (3) extend the perceptual evidence from order reversals to duration/interval perception, that is, demonstrate that the perceived interval between a mask and a reference stimulus may be shortened as well as prolonged by the presence of a masked stimulus. Consequences for theories of visual masking such as asynchronous-updating, perceptual-retouch, and reentrant models are discussed.

No MeSH data available.


Distributions expected in the TOJ (left) and in the scaling and							reproduction task (right). Solid lines depict data expected in unprimed							trials, dotted lines depict data expected in primed trials. PLP is							evident from a shift of the distribution towards the right. Parameters							are indicated on the figures. For a more detailed description, see the							text and Appendix A.
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Figure 2: Distributions expected in the TOJ (left) and in the scaling and reproduction task (right). Solid lines depict data expected in unprimed trials, dotted lines depict data expected in primed trials. PLP is evident from a shift of the distribution towards the right. Parameters are indicated on the figures. For a more detailed description, see the text and Appendix A.

Mentions: Binary psychophysical judgments are typically distributed as a cumulative normal or a logistic function which is defined by two parameters, the point of subjective simultaneity (PSS), and discrimination accuracy (DL; see Figure 2 for an illustration). The PSS is the location on the abscissa at which the two judgments are equally likely, that is, the observers cannot decide about the temporal order. DL is defined as the interquartile range. From the data, the frequency of the judgment “unprimed stimulus first” was calculated, and PSS and DL were computed by logit analysis (Finney, 1971). Further, median judgment times were calculated for each SOA and priming condition.


Temporal processes in prime-mask interaction: Assessing perceptual consequences of masked information.

Scharlau I - Adv Cogn Psychol (2008)

Distributions expected in the TOJ (left) and in the scaling and							reproduction task (right). Solid lines depict data expected in unprimed							trials, dotted lines depict data expected in primed trials. PLP is							evident from a shift of the distribution towards the right. Parameters							are indicated on the figures. For a more detailed description, see the							text and Appendix A.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2864975&req=5

Figure 2: Distributions expected in the TOJ (left) and in the scaling and reproduction task (right). Solid lines depict data expected in unprimed trials, dotted lines depict data expected in primed trials. PLP is evident from a shift of the distribution towards the right. Parameters are indicated on the figures. For a more detailed description, see the text and Appendix A.
Mentions: Binary psychophysical judgments are typically distributed as a cumulative normal or a logistic function which is defined by two parameters, the point of subjective simultaneity (PSS), and discrimination accuracy (DL; see Figure 2 for an illustration). The PSS is the location on the abscissa at which the two judgments are equally likely, that is, the observers cannot decide about the temporal order. DL is defined as the interquartile range. From the data, the frequency of the judgment “unprimed stimulus first” was calculated, and PSS and DL were computed by logit analysis (Finney, 1971). Further, median judgment times were calculated for each SOA and priming condition.

Bottom Line: These models predict that the perceptual latency of a visual backward mask is shorter than that of a like reference stimulus that was not preceded by a masked stimulus.The prediction has been confirmed by studies using temporal-order judgments: For certain asynchronies between mask and reference stimulus, temporal-order reversals are quite frequent (e.g. Scharlau, & Neumann, 2003a).Consequences for theories of visual masking such as asynchronous-updating, perceptual-retouch, and reentrant models are discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Bielefeld University, Germany.

ABSTRACT
Visual backward masking is frequently used to study the temporal dynamics of visual perception. These dynamics may include the temporal features of conscious percepts, as suggested, for instance, by the asynchronous-updating model (Neumann, 1982) and perceptual-retouch theory ((Bachmann, 1994). These models predict that the perceptual latency of a visual backward mask is shorter than that of a like reference stimulus that was not preceded by a masked stimulus. The prediction has been confirmed by studies using temporal-order judgments: For certain asynchronies between mask and reference stimulus, temporal-order reversals are quite frequent (e.g. Scharlau, & Neumann, 2003a). However, it may be argued that these reversals were due to a response bias in favour of the mask rather than true temporal-perceptual effects. I introduce two measures for assessing latency effects that (1) are not prone to such a response bias, (2) allow to quantify the latency gain, and (3) extend the perceptual evidence from order reversals to duration/interval perception, that is, demonstrate that the perceived interval between a mask and a reference stimulus may be shortened as well as prolonged by the presence of a masked stimulus. Consequences for theories of visual masking such as asynchronous-updating, perceptual-retouch, and reentrant models are discussed.

No MeSH data available.