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The role of audience participation and task relevance on change detection during a card trick.

Smith TJ - Front Psychol (2015)

Bottom Line: Failure to detect changes to objects while passively viewing magic tricks has been shown to be conditional on the changing feature being irrelevant to the current task.If the feature was relevant during either the pick-up or put-down action change detection was as good as during the watching block.These results confirm the ability of audience participation to create subtle dynamics of attention and perception during a magic trick and hide otherwise striking changes at the center of attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychological Sciences, Birkbeck, University of London , London, UK.

ABSTRACT
Magicians utilize many techniques for misdirecting audience attention away from the secret sleight of a trick. One technique is to ask an audience member to participate in a trick either physically by asking them to choose a card or cognitively by having them keep track of a card. While such audience participation is an established part of most magic the cognitive mechanisms by which it operates are unknown. Failure to detect changes to objects while passively viewing magic tricks has been shown to be conditional on the changing feature being irrelevant to the current task. How change blindness operates during interactive tasks is unclear but preliminary evidence suggests that relevance of the changing feature may also play a role (Triesch et al., 2003). The present study created a simple on-line card trick inspired by Triesch et al.'s (2003) that allowed playing cards to be instantaneously replaced without distraction or occlusion as participants were either actively sorting the cards (Doing condition) or watching another person perform the task (Watching conditions). Participants were given one of three sets of instructions. The relevance of the card color to the task increased across the three instructions. During half of the trials a card changed color (but retained its number) as it was moving to the stack. Participants were instructed to immediately report such changes. Analysis of the probability of reporting a change revealed that actively performing the sorting task led to more missed changes than passively watching the same task but only when the changing feature was irrelevant to the sorting task. If the feature was relevant during either the pick-up or put-down action change detection was as good as during the watching block. These results confirm the ability of audience participation to create subtle dynamics of attention and perception during a magic trick and hide otherwise striking changes at the center of attention.

No MeSH data available.


Related in: MedlinePlus

Histogram showing the percentage of participants in each Instruction condition that had a particular proportion of change detection (divided into five bins: 0–0.19, 0.2–0.39, 0.4–0.59, 0.6–0.79, 0.8–1.0). Bar colors indicate the Task block (gray = Watching; white = Doing).
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Figure 3: Histogram showing the percentage of participants in each Instruction condition that had a particular proportion of change detection (divided into five bins: 0–0.19, 0.2–0.39, 0.4–0.59, 0.6–0.79, 0.8–1.0). Bar colors indicate the Task block (gray = Watching; white = Doing).

Mentions: The analysis above demonstrated that when the instructions were simple and the feature that changed (i.e., the color) was irrelevant to the task participants reported less changes but only when they are actively performing the task. When participants were passively watching the task and assessing if the instructions were followed correctly the instructions had no impact on change detection. This interaction resulted in the rather counter-intuitive better detection in Watching than Doing for Instruction 1. This change in detection across instruction conditions can also be seen in the distribution of participants who produced particular detection rates (Figure 3). For all conditions other than Doing + Instruction 1, the modal detection proportion was 0.8–1.0. For Doing + Instruction 1 the mode shifted to 0.4 and there was also an increase in the number of participants failing to detect any changes, 21.4% compared to ∼7% for all other conditions (except for 13.3% Watching + Instruction 3). This distribution of detection rates indicates that even in the condition with the worst average detection rate (Doing + Instruction 1) change detection for some participants within this group was very good, whereas other participants were poor. This suggests that the lower cognitive demands of Instruction 1 may have led to some participants paying less attention to the cards and, as a result detecting fewer changes. By comparison, the higher demands of Instructions 2 and 3 gave less opportunity for inattention if participants were to complete the task correctly. However, there is no evidence that participants in Instruction 1 were allocating an insufficient level of attention to the card sorting task as their identification of whether the task was performed correctly during the watching condition (mean accuracy = 0.96, SD = 0.09) was as good as under all other instructions [Instruction 2: accuracy = 0.93, SD = 0.13; Instruction 3: accuracy = 0.98, SD = 0.056; F(36) = 1.154, p = 0.327]. The key difference appears to be the visual features to which attention was allocated, not the overall level of attention.


The role of audience participation and task relevance on change detection during a card trick.

Smith TJ - Front Psychol (2015)

Histogram showing the percentage of participants in each Instruction condition that had a particular proportion of change detection (divided into five bins: 0–0.19, 0.2–0.39, 0.4–0.59, 0.6–0.79, 0.8–1.0). Bar colors indicate the Task block (gray = Watching; white = Doing).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4318204&req=5

Figure 3: Histogram showing the percentage of participants in each Instruction condition that had a particular proportion of change detection (divided into five bins: 0–0.19, 0.2–0.39, 0.4–0.59, 0.6–0.79, 0.8–1.0). Bar colors indicate the Task block (gray = Watching; white = Doing).
Mentions: The analysis above demonstrated that when the instructions were simple and the feature that changed (i.e., the color) was irrelevant to the task participants reported less changes but only when they are actively performing the task. When participants were passively watching the task and assessing if the instructions were followed correctly the instructions had no impact on change detection. This interaction resulted in the rather counter-intuitive better detection in Watching than Doing for Instruction 1. This change in detection across instruction conditions can also be seen in the distribution of participants who produced particular detection rates (Figure 3). For all conditions other than Doing + Instruction 1, the modal detection proportion was 0.8–1.0. For Doing + Instruction 1 the mode shifted to 0.4 and there was also an increase in the number of participants failing to detect any changes, 21.4% compared to ∼7% for all other conditions (except for 13.3% Watching + Instruction 3). This distribution of detection rates indicates that even in the condition with the worst average detection rate (Doing + Instruction 1) change detection for some participants within this group was very good, whereas other participants were poor. This suggests that the lower cognitive demands of Instruction 1 may have led to some participants paying less attention to the cards and, as a result detecting fewer changes. By comparison, the higher demands of Instructions 2 and 3 gave less opportunity for inattention if participants were to complete the task correctly. However, there is no evidence that participants in Instruction 1 were allocating an insufficient level of attention to the card sorting task as their identification of whether the task was performed correctly during the watching condition (mean accuracy = 0.96, SD = 0.09) was as good as under all other instructions [Instruction 2: accuracy = 0.93, SD = 0.13; Instruction 3: accuracy = 0.98, SD = 0.056; F(36) = 1.154, p = 0.327]. The key difference appears to be the visual features to which attention was allocated, not the overall level of attention.

Bottom Line: Failure to detect changes to objects while passively viewing magic tricks has been shown to be conditional on the changing feature being irrelevant to the current task.If the feature was relevant during either the pick-up or put-down action change detection was as good as during the watching block.These results confirm the ability of audience participation to create subtle dynamics of attention and perception during a magic trick and hide otherwise striking changes at the center of attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychological Sciences, Birkbeck, University of London , London, UK.

ABSTRACT
Magicians utilize many techniques for misdirecting audience attention away from the secret sleight of a trick. One technique is to ask an audience member to participate in a trick either physically by asking them to choose a card or cognitively by having them keep track of a card. While such audience participation is an established part of most magic the cognitive mechanisms by which it operates are unknown. Failure to detect changes to objects while passively viewing magic tricks has been shown to be conditional on the changing feature being irrelevant to the current task. How change blindness operates during interactive tasks is unclear but preliminary evidence suggests that relevance of the changing feature may also play a role (Triesch et al., 2003). The present study created a simple on-line card trick inspired by Triesch et al.'s (2003) that allowed playing cards to be instantaneously replaced without distraction or occlusion as participants were either actively sorting the cards (Doing condition) or watching another person perform the task (Watching conditions). Participants were given one of three sets of instructions. The relevance of the card color to the task increased across the three instructions. During half of the trials a card changed color (but retained its number) as it was moving to the stack. Participants were instructed to immediately report such changes. Analysis of the probability of reporting a change revealed that actively performing the sorting task led to more missed changes than passively watching the same task but only when the changing feature was irrelevant to the sorting task. If the feature was relevant during either the pick-up or put-down action change detection was as good as during the watching block. These results confirm the ability of audience participation to create subtle dynamics of attention and perception during a magic trick and hide otherwise striking changes at the center of attention.

No MeSH data available.


Related in: MedlinePlus