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Spatial probability AIDS visual stimulus discrimination.

Druker M, Anderson B - Front Hum Neurosci (2010)

Bottom Line: Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search.This produced fewer spatial repeats and allowed us to dissociate the effect of a high-probability location from that of short-term spatial repetition.These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Waterloo Waterloo, ON, Canada.

ABSTRACT
We investigated whether the statistical predictability of a target's location would influence how quickly and accurately it was classified. Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search. One explanation for probability cuing is spatial repetition priming. In our two experiments we used probability distributions that were continuous across the display rather than relying on a few arbitrary screen locations. This produced fewer spatial repeats and allowed us to dissociate the effect of a high-probability location from that of short-term spatial repetition. The task required participants to quickly judge the color of a single dot presented on a computer screen. In Experiment 1, targets were more probable in an off-center hotspot of high-probability that gradually declined to a background rate. Targets garnered faster responses if they were near earlier target locations (priming) and if they were near the high-probability hotspot (probability cuing). In Experiment 2, target locations were chosen on three concentric circles around fixation. One circle contained 80% of targets. The value of this ring distribution is that it allowed for a spatially restricted high-probability zone in which sequentially repeated trials were not likely to be physically close. Participant performance was sensitive to the high-probability circle in addition to the expected effects of eccentricity and the distance to recent targets. These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect. Future models of attention should consider explicitly incorporating the probabilities of targets locations and features.

No MeSH data available.


Related in: MedlinePlus

Accuracy (above) and correct trial RT (below) in Experiment 1 as a function of whether the trial n back had the same stimulus color and thus required the same response. Mean values are seen at n = 0 and at the corresponding horizontal lines. A future stimulus cannot prime a current one, so the future trial contingencies serve as a visual reference for variability in the data.
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Figure 5: Accuracy (above) and correct trial RT (below) in Experiment 1 as a function of whether the trial n back had the same stimulus color and thus required the same response. Mean values are seen at n = 0 and at the corresponding horizontal lines. A future stimulus cannot prime a current one, so the future trial contingencies serve as a visual reference for variability in the data.

Mentions: Since participants responded to targets that were equally likely to be red or green with consistent button presses, about one half of all trials involved a repeat of color and button press. We refer to this as stimulus–response priming. Figure 5 shows the stimulus–response priming effect for both RT and accuracy when the priming trial was “n” back, similar to the manner of presentation in Maljkovic and Nakayama (1996). Decreases in RT are evident for the preceding four trials and there is a suggestion of an improvement in accuracy as well, perhaps with an even longer time frame. Our LME model examined as the only factor whether the prior trial was of the same color and included the participants as a random effect. A repeat in the stimulus–response was associated with an average decrease in RT of 28 ms (p = 0.0001, 95% CI 25–32 ms).


Spatial probability AIDS visual stimulus discrimination.

Druker M, Anderson B - Front Hum Neurosci (2010)

Accuracy (above) and correct trial RT (below) in Experiment 1 as a function of whether the trial n back had the same stimulus color and thus required the same response. Mean values are seen at n = 0 and at the corresponding horizontal lines. A future stimulus cannot prime a current one, so the future trial contingencies serve as a visual reference for variability in the data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2927278&req=5

Figure 5: Accuracy (above) and correct trial RT (below) in Experiment 1 as a function of whether the trial n back had the same stimulus color and thus required the same response. Mean values are seen at n = 0 and at the corresponding horizontal lines. A future stimulus cannot prime a current one, so the future trial contingencies serve as a visual reference for variability in the data.
Mentions: Since participants responded to targets that were equally likely to be red or green with consistent button presses, about one half of all trials involved a repeat of color and button press. We refer to this as stimulus–response priming. Figure 5 shows the stimulus–response priming effect for both RT and accuracy when the priming trial was “n” back, similar to the manner of presentation in Maljkovic and Nakayama (1996). Decreases in RT are evident for the preceding four trials and there is a suggestion of an improvement in accuracy as well, perhaps with an even longer time frame. Our LME model examined as the only factor whether the prior trial was of the same color and included the participants as a random effect. A repeat in the stimulus–response was associated with an average decrease in RT of 28 ms (p = 0.0001, 95% CI 25–32 ms).

Bottom Line: Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search.This produced fewer spatial repeats and allowed us to dissociate the effect of a high-probability location from that of short-term spatial repetition.These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Waterloo Waterloo, ON, Canada.

ABSTRACT
We investigated whether the statistical predictability of a target's location would influence how quickly and accurately it was classified. Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search. One explanation for probability cuing is spatial repetition priming. In our two experiments we used probability distributions that were continuous across the display rather than relying on a few arbitrary screen locations. This produced fewer spatial repeats and allowed us to dissociate the effect of a high-probability location from that of short-term spatial repetition. The task required participants to quickly judge the color of a single dot presented on a computer screen. In Experiment 1, targets were more probable in an off-center hotspot of high-probability that gradually declined to a background rate. Targets garnered faster responses if they were near earlier target locations (priming) and if they were near the high-probability hotspot (probability cuing). In Experiment 2, target locations were chosen on three concentric circles around fixation. One circle contained 80% of targets. The value of this ring distribution is that it allowed for a spatially restricted high-probability zone in which sequentially repeated trials were not likely to be physically close. Participant performance was sensitive to the high-probability circle in addition to the expected effects of eccentricity and the distance to recent targets. These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect. Future models of attention should consider explicitly incorporating the probabilities of targets locations and features.

No MeSH data available.


Related in: MedlinePlus