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the role of figural context & attention in masking

the role of figural context & attention in masking

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the role of figural context & attention in masking. identification task. A. Williams and Weisstein 1978. identification task. A. Williams and Weisstein 1978. identification task. A. Williams and Weisstein 1978. « Consequently, as well as relying on bottom-up activation, - PowerPoint PPT Presentation

Text of the role of figural context & attention in masking

  • the role of

    figural context & attention

    in masking

  • identification taskA. Williams and Weisstein 1978

  • identification taskA. Williams and Weisstein 1978

  • identification taskA. Williams and Weisstein 1978Consequently, as well as relying on bottom-up activation, the perceptual process may also incorporate a top-down feedbackactivity or a same-level horizontal modulation between therepresentations of context and local features.Breitmeyer and gmen 2006

  • target-mask integrationA. Williams and Weisstein 1981 depth connectedness

  • target-mask integrationA. Williams and Weisstein 1981 depth connectedness

  • target-mask integrationA. Williams and Weisstein 1981 depth connectednessother gestalt factors also modulating masking- collinearity (decreased masking)- symmetry (increased masking)- similarity (increased masking)

  • target-only integrationRamachandran and Cobb 1995, experiment 1

  • target-only integrationRamachandran and Cobb 1995, experiment 1

  • target-only integrationRamachandran and Cobb 1995, experiment 2Constant SOA = 116 ms

    Subjective rating of visibility:Attending squares: 1.17Attending circles: 4.08

  • conclusion (?)figural context modulates the masking function ...

    ... but !

    some researchers may have combined selective attention and grouping

    others have confounded space- or location-based attention with object- or configuration-based attention

  • conclusion (?)figural context modulates the masking function ...

    ... but !

    some researchers may have combined selective attention and grouping

    others have confounded space- or location-based attention with object- or configuration-based attention ...

    ... therefore

    unclear if modulation of masking is due to grouping or space/object-based attention

  • space-based attentional effectsEnns and DiLollo 1997, experiment 1

  • space-based attentional effectsEnns and DiLollo 1997, experiment 1

    masking with four-dot mask not onlydue to low-level contour interactions

  • space-based attentional effectsEnns and DiLollo 1997, experiment 2masking insensitive to contour proximity at parafoveal locations

  • space-based attentional effectsEnns and DiLollo 1997, experiment 3four-dot masking increased with number of targets

  • space-based attentional effectsEnns and DiLollo 1997conclusions

    four-dot masking cannot be explained by contour-based mechanisms commonly used to explain meta-contrast. one explanation might be incomplete focusing of spatial attention

  • space-based attentional effectsEnns and DiLollo 1997conclusions

    four-dot masking cannot be explained by contour-based mechanisms commonly used to explain meta-contrast. one explanation might be incomplete focusing of spatial attention

    ... these data suggest that the need for observers to distribute their attention over all three targets, prior to the onset of the four dots, resulted in masking of even the foveated target shape.

  • space-based attentional effectsTata 2002, experiment 1masking increased with number of targets

  • space-based attentional effectsTata 2002, experiment 2correct attentional cue decreased masking

  • space-based attentional effectsTata 2002, experiment 3pop-out effect reduced masking

  • space-based attentional effectsTata 2002conclusions

    results suggest that theories based on low-level processes early in visual system is insufficient to explain metacontrast masking. visual selective attention plays an important role in metacontrast masking

  • object/feature-based attentional effectsinattentional blindness, is an observed phenomenon of the inability to perceive features in a visual scene when the observer is not attending to them.

  • object/feature-based attentional effectsinattentional blindness, is an observed phenomenon of the inability to perceive features in a visual scene when the observer is not attending to them.

  • object/feature-based attentional effectsinattentional blindness, is an observed phenomenon of the inability to perceive features in a visual scene when the observer is not attending to them. more familiar, typical, or salient visual objects have higher probability of resisting IB, which leads to less masking compared to items less resistant to IB.

  • central attentional effectsmechanisms of masking:

    integration through common synthesis interchannel inhibitionreplacement principleMichaels and Turvey 1979

  • central attentional effectsmechanisms of masking:camouflage masking interruptionEnns and DiLollo 1997another role of attention:increase spatiotemporal resolution of objects presented to nonfoveal regionsmasking by four dots possible because:unattended targets are coded with low spatiotemporal resolution attended four-dot mask have an advantage when competing for higher level mechanisms involved in object recognition

  • central attentional effectsmechanisms of masking:camouflage masking interruptionEnns and DiLollo 1997another role of attention:increase spatiotemporal resolution of objects presented to nonfoveal regionsmasking by four dots possible because:unattended targets are coded with low spatiotemporal resolution attended four-dot mask have an advantage when competing for higher level mechanisms involved in object recognitionObject substitution masking

  • conclusionsfigural context and masking

    gestalt factors influence maskingtarget integrated in an object (2D/3D) is less maskeddifferent temporal properties governs operation of different gestalt factors of figural organizationtarget being part of larger gestalt is masked less than when being part of a meaningless arrangement

    Breitmeyer and gmen 2006

  • conclusionsfigural context and masking

    gestalt factors influence maskingtarget integrated in an object (2D/3D) is less maskeddifferent temporal properties governs operation of different gestalt factors of figural organizationtarget being part of larger gestalt is masked less than when being part of a meaningless arrangement

    attention and masking

    attending features or location of targets enhances visibility of the targetcentrally controlled attention processes mediate transfer of information from iconic levels to post-iconic levels predicts level of performance

    Breitmeyer and gmen 2006

  • conclusionsboth figural context and attention affects visibility of a target, but this is a general feature of attention/figural context when studied in a variety of other experimental paradigms

    Breitmeyer and gmen 2006

  • conclusionsboth figural context and attention affects visibility of a target, but this is a general feature of attention/figural context when studied in a variety of other experimental paradigms

    Thus both top-down influences on backward masking can be viewed simply as modulators of masking analogous to the bottom-up modulatory effects produced by varying certain physical parameters of the target and mask stimuli

    Breitmeyer and gmen 2006

  • thank you

    for your attention

    at the lecture