This research was made possible with startup funds from Arcadia University and Elmhurst College awarded to K.S.M., a student-faculty collaborative grant from Elmhurst College to E.A.W. and K.S.M., and an Arcadia University faculty development grant to K.S.M. We would like to thank Daniel H. Weissman, a collaborator on prior publications using versions of this protocol. We also wish to thank the additional students who collected data on previous versions of this protocol, including Marshall O'Moore, Patricia Chen, Amanda Lai, Elise Darling, Erika Pinsker, Somin Lee, Celine Santos, Greg Ramos, and Kathleen Trencheny.

All of the methods described here were approved by the Arcadia University Institutional Review Board.
1. Design and Prepare the Experiment for Data Collection
NOTE: See the introduction for general information about design and trial types. See the discussion for more information about specific choices that can be made in each of these sub-steps. See Video 1 for a dynamic view of the task, and Video 2 for a slowed down version of the t...

There are several considerations in using this method. The most important step to take is to ensure that the design requires participants to search for two or more targets at a time, and that there are &#34;STC&#34; and &#34;DTC&#34; distractor trial types, as these will provide the researcher with a measure of set-specific capture (STC - DTC). It is also helpful to have an &#34;NTC&#34; trial type to properly measure contingent attentional capture (NTC - STC), though one can estimate NTC performance with Target Alone pe...

Contingent attentional capture refers to a performance cost (slower reaction times and lower accuracy) that occurs when a participant erroneously directs attention to a distractor similar to their search goal. Indexing top-down orienting of attention, contingent attentional capture only occurs when a goal-relevant distractor is present (e.g., a green digit when searching for green letters), but not when a goal-irrelevant stimulus is present (e.g., a blue digit). Studies of contingent attentional capture have been integral to the understanding of top-down orienting and the limitations of information processing, namely, that once a stimulus captures attention, it is processed in a serial and effortful manner1,2,3. Contingent attentional capture is most often measured using static displays that mimic a common visual search, such as searching for a red pepper in the produce section of a grocery store3,4. In this example, an item sharing features with the target, such as a red apple, might capture attention, slowing down the search. Contingent attentional capture can be observed for color3,5,6,7, shape8, motion9, time10, and semantic relevance11,12. In addition to static displays, contingent attentional capture has been measured using dynamic displays that mimic situations such as searching for a landmark while driving along a road, or looking for a person in a quickly moving crowd13,14.
More recently, researchers have investigated the consequences of attending to distractors when more than one search goal is active (such as searching for a red pepper and&#160;garlic at the same time7,8,15,16,17,18,19,20,21,22,23.) In such situations, distraction costs can be especially devastating. While evidence is mixed as to whether multi-goal searches impair performance when distraction is not present, attentional capture from goal-related distractors can cause very large deficits in performance. In particular, we identified a new form of attentional capture called &#34;set-specific capture,&#34; which occurs when multiple goals are concurrently maintained. In the case of set-specific capture, performance costs are especially large when a distractor resembling one target goal (e.g., an apple) grabs attention from the target item matching the other goal (e.g., the garlic)7,20,21,22. See Figure 1 for an explanation of a typical finding, using this grocery example.
As in the case with contingent attentional capture, set-specific capture reveals that information is processed in a serial and effortful manner: when a distractor captures attention, attentional resources are drawn away from the target. In addition, set-specific capture shows that directing attention to the distractor&#39;s features leads to enhancement of the related goal within working memory. Thus, when more than one goal is concurrently maintained, this goal enhancement comes at the expense of any other current goals7,21,22. Set-specific capture is a consequence of multitasking, akin to switch costs and mixing costs found in task-switching studies, but also distinct from these measures24. It is important that future studies investigate this multitasking cost, both in order to understand the magnitude and nature of the impairment for practical reasons (e.g., safety-related situations involving dual-tasking), as well as to refine our understanding of the mechanics of visual search and how goals are maintained. For example, set-specific capture provides support for the idea that a single goal can be focused upon while a target or target-resembling distractor is attended, but that more goals are maintained in an accessory state during visual search25,26,27.
The present method provides a robust way of measuring both contingent attentional capture and set-specific capture within a single paradigm. It uses a dynamic display, inspired by previous work on the attentional blink and contingent attentional capture with rapid serial visual presentations (RSVPs) of stimuli13,14,28,29,30. This type of display yields much larger effects than do static display tasks, which usually rely on reaction time as a dependent measure, rather than accuracy3,31,32. These larger effects allow researchers to use this paradigm to measure more sensitive manipulations of set-specific capture, such as the effect of practice20.
In this task, participants search a heterogeneously colored, centrally-located RSVP for letters appearing in either of two &#34;target&#34; ink colors (e.g., green and orange; see Figure 2 for example stimulus colors). Any time a participant detects a target-colored letter appearing in the central display, they indicate whether the letter was from the first half of the alphabet (&#34;press the &#39;J&#39; key&#34;) or the second half of the alphabet (&#34;press the &#39;K&#39; key&#34;). Meanwhile, participants ignore two RSVP displays consisting of mostly grey letters that appear on either side of the central display. Thus, at any given time, there are three letters on the screen at once - one centrally located and two peripheral. The letters change identity and color every 116 ms.
An experiment may consist of the following trial types: Target Alone, Distractor Alone, Non-Target Colored Distractor (NTC), Same Target Colored Distractor (STC), and Different Target Colored Distractor (DTC). In the Target Alone trial type, a target letter (e.g., a green C) appears in the central RSVP, without any color changes occurring in the peripheral RSVPs preceding it. In the Distractor Alone&#160;trial type, a target-colored item appears in one of the peripheral RSVP displays without a target item appearing afterward. The purpose of this trial type is to prevent participants from using a peripheral color change to predict an upcoming target, by including some trials in which a distractor did not predict a target. In the NTC, STC, and DTC trial types, a colored letter distractor appears in one of the peripheral displays before the target appears centrally, with a &#34;lag&#34; of 1 - 4 display frames (116 - 464 ms) between the appearance of the distractor and the target. For NTC trials, the distractor is not target-colored (e.g., a purple &#39;V&#39;). In STC trials, the distractor (e.g., an orange &#39;B&#39;) is the same color as the following target (e.g., an orange &#39;T&#39;). In DTC trials, the distractor (e.g., an orange &#39;C&#39;) is target-colored, but not the same color as the upcoming target (e.g., a green &#39;V&#39;). See Figure 3 for a schematic of the task, including examples of each trial type. See Video 1 (video) for an example of the task. Viewed on loop, the example includes two targets. Video 2 (video) is the same video at a reduced speed for clarity.
Contingent attentional capture is indicated by the difference between NTC and STC performance, as a target-colored item captures attention only when it bears resemblance to one of the current goals (i.e., not on NTC trials, which usually yield the same accuracy level as Target Alone trials). Set-specific capture is indicated by the difference between STC and DTC performance. We have published several versions of this task, with slightly different configurations of trial types (i.e., with or without NTC and Distractor Alone trials; with just lags 1 and 3, with a variety of target colors, with three targets, etc.7,20,21,22).
One notable feature of this method is that it uses a continuous display. Each trial includes the minimum components to represent that trial type, (e.g., a peripheral distractor, a target, and any letters that appeared in time between the distractor and target.) &#34;Filler&#34; stimuli connect one trial to the next seamlessly, and participants respond during this intertrial interval, whenever they detect a target. The interval lasts from 15 - 21 frames (1740 - 2436 ms), which is sufficient time to respond; most responses occur within 700 ms. An advantage of this method is that chance performance is near 0%; participants are not explicitly aware that a trial has ended if they miss a target item. This allows for three types of outcomes: 1) an identified letter, which will lead to a correct response, 2) a detected but not identified item (e.g., &#34;I saw something green&#34;), which will lead to a 50% chance of a correct response, and 3) an undetected / missed item, which leads to no response (coded as inaccurate). These three outcomes provide more information about the degree of stimulus processing than do tasks with a two alternative forced choice response, which cannot differentiate between detection-without-identification (i.e., a response error) and an outright miss (i.e., an omission error).
We describe the method here as we have used it in published work, in which participants search for colored letters. However, it can be modified for use with images33 and potentially other stimuli, such as words34. Moreover, distractors can appear as other colored items in the central display rather than just as colored letters appearing in the periphery (e.g., a target-colored digit in the central display)21. It is also likely that set-specific capture can be identified in static displays. The further development of the extensions of this method will allow researchers to investigate topics such as the effect of reward and motivation on distraction35, or whether distraction costs are modulated by the number of concurrently maintained goals33. Other applications could include measuring distraction costs in real-world contexts such as when completing a demanding visual search task (e.g., airport baggage screening or radiology screening)36,37,38.

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using rapid serial visual presentation to measure set-specific capture, a consequence of distraction while multitasking

This method uses a rapid serial visual presentation (RSVP) paradigm to measure the cost of distraction when participants maintain multiple search goals. The protocol identifies two types of distraction within a single task - contingent attentional capture and set-specific capture - that represent different types of limitations of cognitive processing. Participants search for letters in two or more &#34;target&#34; ink colors (e.g., green and orange) within a continuous RSVP stream of heterogeneously colored letters, while ignoring two peripheral RSVPs of letters. Upon detecting a target, participants are to identify the letter. On some trials, target-colored distractors appear in the periphery just prior to the presentation of a target, causing a drop in target identification performance. Contingent attentional capture is observed by examining performance on trials in which the peripheral distractor is the same color as the target on that trial (e.g., both orange). Set-specific capture is represented by performance on trials in which the peripheral distractor is target-colored (e.g., orange), but not the same color as the target on that trial (e.g., green.) By varying the amount of time (i.e., the number of stimuli appearing) between the presentation of the distractor and the target, researchers can observe how participants recover from these distraction costs over time. As compared to static displays that are often used to measure contingent attentional capture, the dynamic display produces much larger effects, allowing the researcher to identify subtle effects of smaller manipulations. An unusual aspect of our design is that it employs a continuous display; &#34;filler&#34; stimuli connect one trial to the next seamlessly, and participants respond during this interval whenever they detect a target. The continuous display reduces chance performance to near-zero levels (rather than 50%) and provides researchers with a more sensitive measure of performance differences across trial types.

We report several examples of representative data. In the first example, there were two lags (1 and 3), two distractor trial types (STC and DTC), and 57 participants. There were also Target Alone and Distractor Alone trial types. In a repeated measures ANOVA with the factors trial type and lag, there was a main effect of each factor as well as an interaction between the two. Performance was better at lag 3 (mean (M) = 0.655, standard error (SE) = 0.018) than at lag 1 (<e...

Watch this Scientific Journal Video about Using Rapid Serial Visual Presentation to Measure Set-Specific Capture, a Consequence of Distraction While Multitasking at JoVE.com

Using Rapid Serial Visual Presentation to Measure Set-Specific Capture, a Consequence of Distraction While Multitasking

This method uses a dynamic visual display to index costs of distraction during visual search, including both &#34;contingent attentional capture&#34; and &#34;set-specific capture,&#34; which is a cost of distraction that occurs when the participants maintain multiple search goals simultaneously. This method has revealed basic mechanisms and limitations of visual attention.

This method uses a rapid serial visual presentation (RSVP) paradigm to measure the cost of distraction when participants maintain multiple search goals. ...

This protocol helps researchers investigate distraction while multitasking in a visual search environment. For example, say you're grocery shopping, and you're looking for a red pepper. When you apply attention to this task, you enhance the processing of all similar items such as everything that's red.As a result, everything red will capture your attention and slow down your search. Now, suppose you have more than one item on your grocery list, such as a red pepper and a yellow pepper. To look for more than one item at a time, the processing of information relevant to both items will be enhanced.How does distraction effect multitasking search? Our protocol addresses this question. To investigate this we asked participants to search a rapidly changing central display of color letters and identify all the letters that appear in either of two particular target colors.Occasionally, the gray letters in the left and right displays will change colors, which is distracting. In this slowed down example, there's an orange U target and a green X target. This method can help answer key questions about visual attention, such as how search goals are maintained and used in memory and what are our limitations of multitasking.A major advantage of this technique is that the task produces large effects, providing researchers with the flexibility of measuring nuance aspects of distraction. This technique extends towards applied questions such as how do radiologist search medical images for abnormalities, or how security officers search bags for contraband. Demonstrating the procedure will be Jamie Jasina and Ariel Kershner, undergraduates from the Attention, Memory, and Cognition Laboratory.Before beginning the experiment, select the trial types and the number of trials within each type. For example, in Target Alone trials the target appears without any recent color changes to letters in the periphery. In Distractor Alone trials, a letter in the periphery changes to a target color, but no target appears subsequently in the central display.In Non-target colored distractor trials, a colored letter appears in the periphery just before a target appears centrally, but the distractor is not target colored. In same target colored distractor trials, the colored peripheral item appearing ahead of the target is the same color as that target. In different target colored distractor trials, the colored peripheral item appearing ahead of the target is also target colored, but is not the same color as the target on that trial.Now, select the target distractor lag lengths in each trial type that contain the distractors and targets. And select the target, distractor, and central filler colors for the letters, insuring that target colors are not adjacent on the color wheel. When the task is designed and programed, seat the participant 57 centimeters away from the monitor using a chin rest to enforce this viewing distance, and secure the monitor in a fixed location as necessary.Open the software, navigate to the experiment folder, and enter the experiment script into the command window. Enter the parameters, such as the date and the participant number, and help the participant through the instructions. Supervise the participant during the experiment to ensure that a uniform viewing distance from the monitor is maintained, that the task is being properly completed, and that the participant is not falling asleep or becoming distracted.Remind the participant of the response keys, to slow and consider which response to make after identifying a letter, and that the response will be recorded as correct even if it does not occur immediately. Encourage the participant to take breaks as necessary. This task is very difficult with performances averaging about 75%correct.Be sure to encourage your participants not to become discouraged if they're making many mistakes. When the program concludes, debrief and dismiss the participant. Performance on Target Alone trials is equally good whether participants are looking for one or two targets at the same time.When a peripheral item appears that is not target colored, this is not distracting. When the peripheral distractor and the target are the same color, performance drops as the target color distractor captures attention. The difference in performance between non-target colored trials and same target colored trials is considered contingent attentional capture.When a target colored distractor is not the same color as the subsequent target on that trial, performance plummets. This set specific capture effect is two to three times as large as contingent attentional capture. Set specific capture occurs when an irrelevant stimulus that is related to one goal captures attention and the ability to identify a target matching the other goal is impaired due to a temporary change in how the goals are represented in memory.As well as being so costly, set specific capture takes longer to recover from than does contingent attentional capture. While attempting this procedure, it's important to provide feedback and encouragement. This procedure can be adapted to different stimuli such as images, to determine how distraction effects change when many goals are maintained.Future studies could examine how we search for different features or concepts and may reveal mechanisms of attention and how they relate to memory and perception.

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8.8K vistas.  Arcadia University. This protocol helps researchers investigate distraction while multitasking in a visual search environment. For example, say you're grocery shopping, and you're looking for a red pepper. When you apply attention to this task, you enhance the processing of all similar items such as everything that's red.As a result, everything red will capture your attention and slow down your search. Now, suppose you have more than one item on your grocery list, such as a red pepper and a yellow pepper....