Effects of contrast polarity in paracontrast masking

Kafaligonul, Hulusi; Breitmeyer, Bruno G.; Öğmen, Haluk

doi:10.3758/app.71.7.1576

Cited by 12 publications

(9 citation statements)

References 49 publications

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“…There is evidence that interference from a surrounding ring can occur in a focused attention condition. Studies on paracontrast masking indicate that with different SOAs, polarity, or spatial separation between the target and the ring, a single preceding ring can have a different influence on a subsequent judgment of brightness or contour2829. There is also evidence that changing the brightness of a ring cue can alter its impact on future contrast perception30, which may be explained by paracontrast masking or a sensory interaction between the ring and the stimulus, instead of by attention modulation31.…”

Section: Discussionmentioning

confidence: 99%

Using spatial uncertainty to manipulate the size of the attention focus

Huang

Liu

Wang

et al. 2016

Sci Rep

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Preferentially processing behaviorally relevant information is vital for primate survival. In visuospatial attention studies, manipulating the spatial extent of attention focus is an important question. Although many studies have claimed to successfully adjust attention field size by either varying the uncertainty about the target location (spatial uncertainty) or adjusting the size of the cue orienting the attention focus, no systematic studies have assessed and compared the effectiveness of these methods. We used a multiple cue paradigm with 2.5° and 7.5° rings centered around a target position to measure the cue size effect, while the spatial uncertainty levels were manipulated by changing the number of cueing positions. We found that spatial uncertainty had a significant impact on reaction time during target detection, while the cue size effect was less robust. We also carefully varied the spatial scope of potential target locations within a small or large region and found that this amount of variation in spatial uncertainty can also significantly influence target detection speed. Our results indicate that adjusting spatial uncertainty is more effective than varying cue size when manipulating attention field size.

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Section: Discussionmentioning

confidence: 99%

Using spatial uncertainty to manipulate the size of the attention focus

Huang

Liu

Wang

et al. 2016

Sci Rep

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“…As in the pre-stimulus interval, a variable inter-trial interval (1000 ± Δ ms, with 0 ≤ Δ ≤ 150). The contour discrimination task was employed based on the previous findings indicating that this perceptual task reflects changes in target visibility due to both paracontrast and metacontrast (Breitmeyer 1978a;Kafaligönül et al 2009). In particular, used both 1 3 brightness matching (i.e., direct assessment of target visibility) and contour discrimination tasks in the same experimental design.…”

Section: Design and Proceduresmentioning

confidence: 99%

“…Interestingly, the same mask polarity increased the target visibility in this SOA range. An important question to ask is whether the facilitatory mechanisms proposed to take place in short and/or negative (i.e., paracontrast) SOAs have a role in this enhancement (Bachmann 1988(Bachmann , 1994Kafaligönül et al 2009;Wutz et al 2018). Future research, including systematic manipulations of polarity, M/T energy ratio (e.g., changes in duration or contrast), and criterion content, will be informative to have a better understanding of across and within pathway interactions in the temporal domain.…”

Section: Metacontrast Masking Across Different Polaritiesmentioning

confidence: 99%

Neural correlates of metacontrast masking across different contrast polarities

2021

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Metacontrast masking is a powerful illusion to investigate the dynamics of perceptual processing and to control conscious visual perception. However, the neural mechanisms underlying this fundamental investigative tool are still debated. In the present study, we examined metacontrast masking across different contrast polarities by employing a contour discrimination task combined with EEG (Electroencephalography). When the target and mask had the same contrast polarity, a typical U-shaped metacontrast function was observed. A change in mask polarity (i.e., opposite mask polarity) shifted this masking function to a monotonic increasing function such that the target visibility was strongly suppressed at stimulus onset asynchronies less than 50 ms. This transition in metacontrast function has been typically interpreted as an increase in intrachannel inhibition of the sustained activities functionally linked to object visibility and identity. Our EEG analyses revealed an early (160-300 ms) and a late (300-550 ms) spatiotemporal cluster associated with this effect of polarity. The early cluster was mainly over occipital and parieto-occipital scalp sites. On the other hand, the later modulations of the evoked activities were centered over parietal and centro-parietal sites. Since both of these clusters were beyond 160 ms, the EEG results point to late recurrent inhibitory mechanisms. Although the findings here do not directly preclude other proposed mechanisms for metacontrast, they highlight the involvement of recurrent intrachannel inhibition in metacontrast masking.

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“…Some previous work saw the interference of surrounding ring in focused attention condition. Studies on paracontrast masking revealed that with different SOA or polarity or spatial separation between the target and the ring, a single preceding ring could have varied influence on later judgment of brightness or contours (Breitmeyer et al, 2006;Kafaligönül et al, 2009). It also showed that changing the brightness of circle cue could alter its influence on contrast perception (Schneider, 2006), which should be explained by paracontrast masking, a sensory interaction between the circle and the stimulus instead of by attention modulation (Ling et al, 2007).…”

Section: No Impact Of Ring Size In Cue Conditionmentioning

confidence: 99%

Inhibition Effect of Spatial Attention on Surroundings in Discrimination Task

Liu

Zhang

et al. 2018

Neuroquantology

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The cue size effect which is characterized as a reverse relationship between the cue size and the detection speed is regarded as a proof for adjustment of the attentional field according to the cue size. This effect was mainly found in detection experiments. As several studies have shown that cues had discrepant effects in visual detection and discrimination task, it's natural to ask whether cue size effect still exist in discrimination task. The probability exists that the influence of cue size differ in these two basic types of behavioral tasks. To solve the problem, we assessed the interference of surrounding ring on discrimination at its center with a multiple cuing design. The results show that in distributed neutral condition when no single place gains overwhelming advantage from attention, ring size has a positive correlation with the discrimination speed. However, when the exact place of impending target is cued and spatial attention takes effect, variance in surrounding ring size makes no difference on discrimination. This type of result pattern doesn't depend on what is discriminated (orientation or brightness) or how the spatial attention is induced (by peripheral ring cue or central symbolic line cue). Our findings add evidence to the view that detection and discrimination should not be considered as the same. We also propose that with sufficient time, attention suppresses the impact from the vicinity.

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Effects of contrast polarity in paracontrast masking

Cited by 12 publications

References 49 publications

Using spatial uncertainty to manipulate the size of the attention focus

Using spatial uncertainty to manipulate the size of the attention focus

Neural correlates of metacontrast masking across different contrast polarities

Inhibition Effect of Spatial Attention on Surroundings in Discrimination Task

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