The authors have no acknowledgements.

NOTE: All subjects must give informed written consent before the experimental protocol. All procedures, consent forms, and the experimental protocol must be approved by the local Committee for the Protection of Human Subjects.
1. Preparing the Subject for the Experiment
<ol>
	<li>Recruit participants from the local area and compensate them for their time. The participants must have normal or corrected-to-normal visual acuity and English as their first language.</li>
</ol>
2. Stimuli
<ol>
	<li>Choose at least seven different categories from Battig and Montague9 to use in the target detection task explained below.</li>
	<li>Choose nouns from the category norms you selected in Battig and Montaque9 to use as targets as well as other words from separate categories to use as decoys in the target detection task explained below. Make sure the set of words collected in this step is large enough so each subject can be tested with many trails without repeatedly using the same target.</li>
	<li>Choose nouns from the Penn Treebank corpus, with frequency higher than 1 per million10 to use as nontargets and distractors to be tested against the nontarget nouns in the memory task explained below. Make sure the set of words collected in this step is also large enough so that repeatedly using a word can be avoided for a given subject.</li>
	<li>Choose words 4 or 5 letters in length. Trials can be divided into 4-letter words trials and 5-letter words trials. Use only 4-letter words for 4-letter words trials, and 5-letter words for 5-letter words trials.</li>
	<li>For each trial, randomly select 1 target and 1 decoy that are prepared in step 2.2; from the set that are prepared in step 2.3, randomly select 7 words as nontargets and 5 words as memory task distractors. Make sure the words are never repeated in a given trial.</li>
</ol>
3. Collect Information from the Participant
<ol>
	<li>Before the actual experiment begins, add a section into your experiment, or create a piece of paper to record information about the participant (name, age, handedness, gender).</li>
</ol>
4. Display Instructions
<ol>
	<li>Make sure the participants understand and fully read the instructions.</li>
	<li>Clearly state that there are two tasks in the experiment, first the participants have to detect the presence or absence of a target noun in a displayed category. Second, participants will be tested on other words in the sequence, so participants must try to remember all the words in the RSVP task described below.</li>
	<li>Make the response keys clear and easy to remember.</li>
</ol>
5. Rapid Serial Visual Presentation (RSVP)
<ol>
	<li>Use A 21-inch CRT monitor, or equivalent (refresh rate = 85 Hz, resolution = 1,280 x 1,024 pixels) to display the stimuli. Use standard scientific software and a stimuli presentation toolbox to run the experiment. Present the words in black and Courier font (size 14) on a white background.</li>
	<li>Start each trial with a display of the target category for 1.2 sec, followed by a fixation cross for 500 msec and a blank screen for 200 msec. Next, present 8 nouns using SOAs of either 120, 240, or 360 msec/item making sure distractor nouns are never used as target nouns across trials. Each trial takes about 10 sec. 
	NOTE: in total, there were 96 trials and 8 practice trials in the exemplar experiment 1, including 16 repetitions for each condition. A typical session with this experimental design will take a subject 15&#8211;20 min to complete.</li>
</ol>
6. Target Detection Task
<ol>
	<li>Prepare two nouns, one belonging to the target category and the other not belonging to the target category (a decoy noun), for every trial. In half of the trials, present the target noun. And in the other half of the trials, present the decoy noun. Ensure the target position is never one of the first or last positions in the presentation.</li>
	<li>After the RSVP, give participants 2 sec to respond &#8220;Yes&#8221; or &#8220;No&#8221; to indicate whether the presentation contained a word from the target category.</li>
</ol>
7. Recognition Memory Task for Nontargets
<ol>
	<li>Present the first recognition memory task for nontargets after the 2-sec interval for response to the categorical task. 
	NOTE: this first memory task is always a word either immediately before or immediately after the target word in the sequence, or in the middle of the sequence for trials not containing a target word.</li>
	<li>Show the test word randomly on the right or left side of the screen next to a word that was not in the sequence, acquired from protocol step 2.2.</li>
	<li>Keep these words on the screen until participants make a response using the left or right arrow key, corresponding to the position of the word that was displayed in the sequence.</li>
	<li>Present the second memory test after the response, using a word in the sequence not directly before or after the target, to keep participants from paying extra attention to the words around the target. Use the same procedure as the first memory task.</li>
	<li>To avoid fatigue or eye strain, encourage participants to take rests between experimental trials. Participants usually do not need more than a few seconds to rest between consecutive trials.</li>
</ol>
8. Counterbalanced SOA Memory Task
<ol>
	<li>If interested in examining AB effects on more nontarget items, in a second experiment, use the same RSVP procedure with a counterbalanced, between-subject design. 
	NOTE: In the demonstrative study, the SOAs of 120 or 240 msec were counterbalanced between participants. Other SOAs can be tested as well. This experiment does not need to be conducted with the same participants or in the same sessions as the first experiment.</li>
	<li>Use three memory tests after the detection task for this experiment. Make sure that the test words are equally likely to be from positions 2 through 7 around the target for target present trials, or around the decoy noun in the target absent trials. 
	NOTE: the procedure and button press is the same as the first experiment.</li>
</ol>
9. Wrapping up
<ol>
	<li>De-brief with the participants if they are interested in the purpose of the study. To protect participant&#8217;s privacy, identifying information about participants (e.g., name) should be removed and replaced with number coding to be affiliated with the data file.</li>
	<li>If needed, when data from multiple participants are collected, use ANOVAs or planned contrast t-tests to compare memory performances in target present versus target absent conditions. 
	NOTE: We suggest to focus on the data from correctly answered trials of the target detection task, as participant&#8217;s attention may be unfocused in incorrectly answered trials of the target detection task.</li>
</ol>

<ol>
	<li>Raymond, J. E., Shapiro, K. L., Arnell, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temporary+suppression+of+visual+processing+in+an+RSVP+task:+An+attentional+blink.">Temporary suppression of visual processing in an RSVP task: An attentional blink.</a> J Exp Psychol Hum Percept Perform. 18 (3), 849-860 (1992).</li><li>Dux, P. E., Marois, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+attentional+blink:+A+review+of+data+and+theory.">The attentional blink: A review of data and theory.</a> Atten Percept Psychophys. 71 (8), 1683-1700 (2009).</li><li>Desimone, R., Duncan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+mechanisms+of+selective+visual+attention.">Neural mechanisms of selective visual attention.</a> Annu Rev Neurosci. 18 (1), 193-222 (1995).</li><li>Reynolds, J. H., Heeger, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+normalization+model+of+attention.">The normalization model of attention.</a> Neuron. 61 (2), 168-185 (2009).</li><li>Nieuwenstein, M. R., Potter, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temporal+Limits+of+Selection+and+Memory+Encoding:+A+Comparison+of+Whole+versus+Partial+Report+in+Rapid+Serial+Visual+Presentation.">Temporal Limits of Selection and Memory Encoding: A Comparison of Whole versus Partial Report in Rapid Serial Visual Presentation.</a> Psychol Sci. 17 (6), 471-475 (2006).</li><li>Potter, M. C., Nieuwenstein, M., Strohminger, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole+report+versus+partial+report+in+RSVP+sentences.">Whole report versus partial report in RSVP sentences.</a> J Mem Lang. 58 (4), 907-915 (2008).</li><li>Loach, D., Mar&#237;-Beffa, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Post-target+inhibition:+A+temporal+binding+mechanism.">Post-target inhibition: A temporal binding mechanism.</a> Visual Cognition. 10 (5), 513-526 (2003).</li><li>Meng, M., Potter, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+attentional+blink+for+nontargets.">An attentional blink for nontargets.</a> Atten Percept Psychophys. 73 (2), 440-446 (2010).</li><li>Battig, W. F., Montague, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Category+norms+for+verbal+items+in+56+categories.">Category norms for verbal items in 56 categories.</a> J. Exp. Psychol. 80 (3), 46 (1969).</li><li>Marcus, M. P., Marcinkiewicz, M. A., Santorini, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Building+a+large+annotated+corpus+of+English:+The+Penn+Treebank.">Building a large annotated corpus of English: The Penn Treebank.</a> Computational linguistics. 19 (2), 313-330 (1993).</li></ol>

The authors have nothing to disclose.

This novel dual-task approach combined a categorical RSVP detection task with two-alternative forced choice memory tasks immediately following the detection task. Our representative results replicate a previously published study8, showing that target detection may impair memory encoding of nontargets that are presented after the target, especially at the lag-2 position in RSVP. At a glance, this is an effect similar to AB with lag-1 sparing that suggests transient attention modulated by target detection8. However, conventional AB paradigm can only test the effect of attention on targets. Using the conventional AB paradigm, as participants need to maintain the description of targets in working memory, it would be impossible to tease apart any effects caused by transient attention versus effects of working memory. By contrast, our paradigm allows investigations of the temporal properties of visual attention by probing the encoding of nontargets, therefore independent of target-to-target interactions. Using this paradigm, experimenters can test whether theories of spatial attention can be extended to temporal proximities. 
Counterbalancing the order of testing and the exact lags in the two-alternative forced choice memory task will allow experimenters to interpret their results with confidence. Researchers should be careful about the selection of the words in RSVP sequence. The length and familiarity should be kept roughly the same among the words; otherwise the results may be biased. On the other hand, SOA and the number of words in RSVP can be changed to allow flexibility in testing effects of attention across various temporal ranges. These changes should not bias experimental results as long as experimental conditions are all otherwise counterbalanced.
This dual-task paradigm is very demanding for the attention of participants. Participants should practice before the real experiment, in order to be able to look for a target word in the RSVP sequence and try to remember the words in the sequence at the same time. In addition, the verbal ability of participants needs to be controlled for to avoid introducing confounding factors. For example, in our exemplar experiments, participants were native English speakers recruited from a university in the US. This requirement of the verbal knowledge of English limits our paradigm in testing English native speaking populations. If a different population is tested, stimulus words must be created in the native language of that population.
Using the current design, more studies can be done to test the importance and specificity of attentional blink as well as periods of transient attention following targets. Future applications of this technique include looking more closely at temporal properties of attention that may complement the current attentional models noted previously that only focus on spatial attention. This technique may also be used for other categories besides nouns, such as pictures and sounds, and can be easily combined with fMRI and MEG techniques to examine neural correlates of attentional effects.

Rapid Serial Visual Presentation (RSVP) has been used to show that there is an attentional blink (AB) when two targets are presented sequentially within about 500 msec1. If the second target is presented within about 150 msec, however, there is enhancement in the processing of both targets (e.g., lag-1 sparing)2. A similar phenomenon has been found in spatial attention studies. Both the biased competition model of selective attention3 and the normalization model of attention4 suggest that attention enhances the processing of items presented in the attended location but suppresses the processing of nearby items. Could this spatial proximity suppression also explain the temporal AB of subsequent items, both nontargets and targets?
Past studies have looked at memory of a presentation of items and found AB when participants were instructed to partially report the sequence of items, but not when participants were instructed to report the entire sequence5,6. These results suggest that when attention is allocated over all the words in a sequence, there is no AB, and the span of attention is large. Since the above experiment included all or half of the words as targets, what would happen if participants were told to only look for one target, and all other words were nontargets? Is there AB for nontargets?
Loach and Mari-Beffa published a study about the influence of target detection on memory for distractors, and found the memory for a distractor was inhibited based on its proximity to the target7. This indirect design, however, was limited to using only four letters (X, H, S, and O), with any of the letters being a target, critical distractor, or probe. Letters that were never presented as targets or probes would be the remaining distractors.
To overcome the limitations in previous studies, a novel dual-task procedure was developed by Meng and Potter to investigate whether the detection of a target would suppress processing of nearby nontargets8. This paper describes this procedure in detail. First, participants searched a sequence of RSVP words for a categorical target word. Second, there was a memory task involving words that were present in the RSVP task, but were not the target. In this procedure, the nontarget words were distractors. The nontarget words, which would be tested in the memory task, had to be attended and remembered by the subject. In each trial, new words would be used; therefore nontarget words were never presented as a target.

<table><tbody><tr><td>Dell CRT Monitor</td><td>Dell Inc.</td><td>P1130</td><td>21-inch, refresh rate = 85&amp;nbsp;Hz, resolution = 1,280 x 1,024 pixels, 16 bits color depth</td></tr><tr><td>Apple Macintosh Computer</td><td>Apple Inc.</td><td>A1278</td><td></td></tr><tr><td>MATLAB</td><td>The MathWorks Inc.</td><td>R2009b</td><td></td></tr><tr><td>Psychophysics Toolbox for MATLAB</td><td></td><td>PTB-3</td><td>This toolbox is used to present stimuli and collect behavioral data.</td></tr></tbody></table>

a dual task procedure combined with rapid serial visual presentation to test attentional blink for nontargets

When viewers search for targets in a rapid serial visual presentation (RSVP) stream, if two targets are presented within about 500 msec of each other, the first target may be easy to spot but the second is likely to be missed. This phenomenon of attentional blink (AB) has been widely studied to probe the temporal capacity of attention for detecting visual targets. However, with the typical procedure of AB experiments, it is not possible to examine how the processing of non-target items in RSVP may be affected by attention. This paper describes a novel dual task procedure combined with RSVP to test effects of AB for nontargets at varied stimulus onset asynchronies (SOAs). In an exemplar experiment, a target category was first displayed, followed by a sequence of 8 nouns. If one of the nouns belonged to the target category, participants would respond &#8216;yes&#8217; at the end of the sequence, otherwise participants would respond &#8216;no&#8217;. Two 2-alternative forced choice memory tasks followed the response to determine if participants remembered the words immediately before or after the target, as well as a random word from another part of the sequence. In a second exemplar experiment, the same design was used, except that 1) the memory task was counterbalanced into two groups with SOAs of either 120 or 240 msec and 2) three memory tasks followed the sequence and tested remembrance for nontarget nouns in the sequence that could be anywhere from 3 items prior the target noun position to 3 items following the target noun position. Representative results from a previously published study demonstrate that our procedure can be used to examine divergent effects of attention that not only enhance targets but also suppress nontargets. Here we show results from a representative participant that replicated the previous finding.&#160;

For experiment 1, the representative subject&#8217;s accuracy for detecting a noun in the target category over SOAs was 72% at 120 msec, 91% at 240 msec, and 94% for 360 msec. For the memory task, only correctly answered trials of the target detection task were used, and trials were separated based on the presence or absence of a categorical target noun and then split into subsets based on their positions corresponding to the target noun, or their serial positions corresponding to the decoy target noun in target absent trials. Figure 1 shows the results of the first memory task for the representative subject. The subject showed difficulty remembering targets immediately after the category noun for both 120 and 240 msec SOAs, but fairly high accuracy with encoding at 360 msec SOA. Words that were immediately before the category noun were all remembered with fairly high accuracy. When there was no target present in the RSVP sequence at 120 and 240 msec SOAs, memory was better for words later in the sequence than early in the sequence, while all nontarget words were easily remembered with 360 msec SOA. Figure 2 shows the results of the second memory task. The words were put into subsets based on whether they were presented before or after the target serial position in RSVP.
For experiment 2, category noun detection accuracy was 80% for the 120 msec SOA condition and 93% for the 240 msec SOA condition, where the serial positions of the target noun were the same as in experiment 1. Figure 3 shows results for the 120 msec SOA condition. Note that the tested words were equally likely to be from any position 3 words before the target noun (or at the corresponding serial position in the target absent trials) to 3 words following the target noun (or at the corresponding serial position in the target absent trials), excluding the first and last word in the sequence. All items from lag -3, -2, and -1 were remembered around 70% of the time independent of whether the target was present or absent. At lag 1, 2, and 3 in target absent trials, nontarget words were remembered more accurately, while memory for nontarget words at lag 2 was hindered the most in target present trials. Figure 4 shows results for the 240 msec SOA experiment. Again, memory for nontarget words at lag 2 was worse if there was a target present in the trial.
These results largely replicate a previously published paper8 that used the same experimental protocol, suggesting robust effectiveness of the present experimental paradigm.
<img alt="Figure 1" src="/files/ftp_upload/52374/52374fig1highres.jpg" /> 
Figure 1. Results of exemplar experiment 1, first memory test for one representative subject: two-alternative forced-choice recognition of the word immediately before the target or control (left) and immediately after the target or control (right).
<img alt="Figure 2" src="/files/ftp_upload/52374/52374fig2highres.jpg" /> 
Figure 2. Results of exemplar experiment 1, second memory test for one representative subject: two-alternative forced-choice of a word before (left) or after (right) the target or control, excluding the two words adjacent to the target.
<img alt="Figure 3" src="/files/ftp_upload/52374/52374fig3highres.jpg" /> 
Figure 3. Results of exemplar experiment 2, memory test for one representative subject in the 120 msec SOA condition: accuracy as a function of lag relative to target or control position in RSVP.
<img alt="Figure 4" src="/files/ftp_upload/52374/52374fig4highres.jpg" /> 
Figure 4. Results of exemplar experiment 2, memory test for one representative subject in the 240 msec SOA condition: accuracy as a function of lag relative to target or control position in RSVP.

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A Dual Task Procedure Combined with Rapid Serial Visual Presentation to Test Attentional Blink for Nontargets

This paper describes a novel dual task procedure combined with Rapid Serial Visual Presentation to look at attentional blink at varied stimulus onset asynchronies. This experimental procedure differed from others in that it tested attentional blink for nontargets.

When viewers search for targets in a rapid serial visual presentation (RSVP) stream, if two targets are presented within about 500 msec of each other, the ...

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9.1K Views.  Dartmouth College. This paper describes a novel dual task procedure combined with Rapid Serial Visual Presentation to look at attentional blink at varied stimulus onset asynchronies. This experimental procedure differed from others in that it tested attentional blink for nontargets.

Video: A Dual Task Procedure Combined with Rapid Serial Visual Presentation to Test Attentional Blink for Nontargets

Measuring Attentional Biases for Threat in Children and Adults

Investigators have long been interested in the human propensity for the rapid detection of threatening stimuli. However, until recently, research in this domain has focused almost exclusively on adult participants, completely ignoring the topic of threat detection over the course of development. One of the biggest reasons for the lack of developmental work in this area is likely the absence of a reliable paradigm that can measure perceptual biases for threat in children. To address this issue, we recently designed a modified visual search paradigm similar to the standard adult paradigm that is appropriate for studying threat detection in preschool-aged participants. Here we describe this new procedure. In the general paradigm, we present participants with matrices of color photographs, and ask them to find and touch a target on the screen. Latency to touch the target is recorded. Using a touch-screen monitor makes the procedure simple and easy, allowing us to collect data in participants ranging from 3 years of age to adults. Thus far, the paradigm has consistently shown that both adults and children detect threatening stimuli (e.g., snakes, spiders, angry/fearful faces) more quickly than neutral stimuli (e.g., flowers, mushrooms, happy/neutral faces). Altogether, this procedure provides an important new tool for researchers interested in studying the development of attentional biases for threat.

Here we describe a touch-screen visual search paradigm that can be used to study threat detection across the lifespan. The paradigm has already been used in various studies demonstrating that both children and adults detect threatening stimuli like snakes, spiders, and angry faces faster than non-threatening stimuli.

Investigators have long been interested in the human propensity for the rapid detection of threatening stimuli. However, until recently, research in this ...

Methods to Test Visual Attention Online

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative data samples than can typically be collected on college campuses. However, before such methods can be widely adopted, a number of technological challenges must be overcome &#8211; in particular in experiments where tight control over stimulus properties is necessary. Here we present methods for collecting performance data on two tests of visual attention. Both tests require control over the visual angle of the stimuli (which in turn requires knowledge of the viewing distance, monitor size, screen resolution, etc.) and the timing of the stimuli (as the tests involve either briefly flashed stimuli or stimuli that move at specific rates). Data collected on these tests from over 1,700 online participants were consistent with data collected in laboratory-based versions of the exact same tests. These results suggest that with proper care, timing/stimulus size dependent tasks can be deployed in web-based settings.

To replicate laboratory settings, online data collection methods for visual tasks require tight control over stimulus presentation. We outline methods for the use of a web application to collect performance data on two tests of visual attention.

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative ...

Measurement of Neurophysiological Signals of Ignoring and Attending Processes in Attention Control

Attention control is the ability to selectively attend to some sensory signals while ignoring others. This ability is thought to involve two processes: enhancement of sensory signals that are to be attended and the attenuation of sensory signals that are to be ignored. The overall strength of attentional modulation is often measured by comparing the amplitude of a sensory neural response to an external input when attended versus when ignored. This method is robust for detecting attentional modulation, but precludes the ability to assess the separate dynamics of attending and ignoring processes. Here, we describe methodology to measure independently the neurophysiological signals of attending and ignoring using the intermodal attention task (IMAT). This task, when combined with electroencephalography, isolates neurophysiological sensory responses in auditory and visual modalities, when either attending or ignoring, with respect to a passive control. As a result, independent dynamics of attending and of a ignoring can be assessed in either modality. Our results using this task indicate that the timing and cortical sources of attending and ignoring effects differ, as do their contributions to the attention modulation effect, pointing to unique neural trajectories and demonstrating sample utility of measuring them separately.

Attention control comprises enhancement of target signals and attenuation of distractor signals. We describe an approach to measure separately but concurrently, the neurophysiology of attending and ignoring in sustained intermodal attention, utilizing a passive control condition during which neither process is continuously engaged.

Attention control is the ability to selectively attend to some sensory signals while ignoring others. This ability is thought to involve two processes: ...

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

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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. ...

Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity

This experimental protocol was designed to investigate whether visual attention is obligatorily deployed at the endpoint of saccades. To this end, we recorded the eye position of human participants engaged in a saccade task via eye tracking and assessed visual orientation discrimination performance at various locations during saccade preparation. Importantly, instead of using a single saccade target paradigm for which the saccade endpoint typically coincides roughly with the target, this protocol comprised the presentation of two nearby saccade targets, leading to a distinct spatial dissociation between target locations and saccade endpoint on a substantial number of trials. The paradigm allowed us to compare presaccadic visual discrimination performance at the endpoint of accurate saccades (landing at one of the saccade targets) and of averaging saccades (landing at an intermediate location in between the two targets). We observed a selective enhancement of visual sensitivity at the endpoint of accurate saccades but not at the endpoint of averaging saccades. Rather, before the execution of averaging saccades, visual sensitivity was equally enhanced at both targets, suggesting that saccade averaging follows from unresolved attentional selection among the saccade targets. These results argue against a mandatory coupling between visual attention and saccade programming based on a direct measure of presaccadic visual sensitivity rather than saccadic reaction times, which have been used in other protocols to draw similar conclusions. While our protocol provides a useful framework to investigate the relationship between visual attention and saccadic eye movements at the behavioral level, it can also be combined with electrophysiological measures to extend insights at the neuronal level.

This experimental protocol combined eye tracking and the assessment of presaccadic visual sensitivity in a dual task paradigm, consisting of a free choice saccade task and a visual discrimination task, to investigate the deployment of visual spatial attention before both, accurate and averaging saccades.

This experimental protocol was designed to investigate whether visual attention is obligatorily deployed at the endpoint of saccades. To this end, we ...

Eye Tracking During A Complex Aviation Task For Insights Into Information Processing

Eye tracking has been used extensively as a proxy to gain insight into the cognitive, perceptual, and sensorimotor processes that underlie skill performance. Previous work has shown that traditional and advanced gaze metrics reliably demonstrate robust differences in pilot expertise, cognitive load, fatigue, and even situation awareness (SA).
This study describes the methodology for using a wearable eye tracker and gaze mapping algorithm that captures naturalistic head and eye movements (i.e., gaze) in a high-fidelity flight motionless simulator. The method outlined in this paper describes the area of interest (AOI)-based gaze analyses, which provides more context related to where participants are looking, and dwell time duration, which indicates how efficiently they are processing the fixated information. The protocol illustrates the utility of a wearable eye tracker and computer vision algorithm to assess changes in gaze behavior in response to an unexpected in-flight emergency.
Representative results demonstrated that gaze was significantly impacted when the emergency event was introduced. Specifically, attention allocation, gaze dispersion, and gaze sequence complexity significantly decreased and became highly concentrated on looking outside the front window and at the airspeed gauge during the emergency scenario (all p values &#60; 0.05). The utility and limitations of employing a wearable eye tracker in a high-fidelity motionless flight simulation environment to understand the spatiotemporal characteristics of gaze behavior and its relation to information processing in the aviation domain are discussed.

Eye tracking is a non-invasive method to probe information processing. This article describes how eye tracking can be used to study gaze behavior during a flight simulation emergency task in low-time pilots (i.e., &lt;350 flight hours).

Eye tracking has been used extensively as a proxy to gain insight into the cognitive, perceptual, and sensorimotor processes that underlie skill ...

Gaze-Contingent Framework for Studying and Training in Simulated Vision Loss

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

Macular degeneration (MD) is one of the leading causes of vision impairment in the Western world. Patients with MD tend to develop spontaneous eye movement strategies to compensate for their vision loss, including adopting a preferred retinal locus, or PRL, a spared peripheral region that they use more frequently to replace the damaged fovea. However, not all patients are successful in developing a PRL, and even when they do, it might take them months. Currently, no gold standard rehabilitative therapy exists, and MD research is further hindered by issues of recruitment, compliance, and comorbidity. To help address these issues, a growing body of research has used eye tracking-guided, gaze-contingent displays in a simulated central vision loss paradigm in individuals with intact vision. While simulated vision loss is qualitatively different than pathological central vision loss, our framework provides for a highly controlled model through which to study compensatory eye movements and test possible rehabilitation interventions in low vision. By developing a comprehensive framework, rather than relying on isolated and disconnected tasks, we create a cohesive environment where we can test larger-scale hypotheses, allowing us to examine interactions between tasks, assess training effects across multiple measures, and establish a consistent methodology for future research. Furthermore, participants in simulated central vision loss studies show similarities in their oculomotor compensatory behaviors compared to patients with MD. Here, we present a framework for conducting gaze-contingent studies related to simulated central vision loss. We emphasize the utilization of the framework to test behavioral and oculomotor performance of healthy individuals on a wide range of perceptual tasks encompassing different levels of visual processing. We also discuss how this framework can be adapted for training MD patients.

Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss

We present development of a gaze-contingent display framework designed for perceptual and oculomotor research simulating central vision loss. This framework is particularly adaptable for studying compensatory behavioral and oculomotor strategies in individuals experiencing both simulated and pathological central vision loss.

Macular degeneration (MD) is one of the leading causes of vision impairment in the Western world. Patients with MD tend to develop spontaneous eye ...

Neuroscience

Multiple Object Tracking

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University

In a staggeringly complex and engaging world, it is crucial to selectively process some stimuli at the expense of others. Experimental psychologists call this ability attention. Specifically, visual attention refers to the ability to selectively process aspects of a visual scene.
Many paradigms used to study visual attention involve brief, punctuated, and repeated trials. However, everyday situations often place sustained demands on attention, as opposed to requiring only brief focus. For example, compare driving through busy city streets, which demands sustained attention, with crossing a busy street, which demands just a few moments of caution. To investigate sustained visual attention, experimental psychologists typically rely on a paradigm called multiple object tracking.
This video demonstrates standard procedures for investigating sustained visual attention through multiple object tracking.

Multiple Object Tracking: Studying Sustained Visual Attention

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University

In a staggeringly complex and engaging world, it is crucial to selectively process ...

Education

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Psychology

Cognitive Psychology

Inattentional Blindness

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
We generally think that we see things pretty well if they are close by and right in front of us. But do we? We know that visual attention is a property of the human brain that controls what parts of the visual world we process, and how effectively. Limited attention means that we can't process everything at once, it turns out, even things that might be right in front of us. 
In the 1960s, the renowned cognitive psychologist Ulrich Neisser began to demonstrate experimentally that people can be blind to objects that are right in front of them, literally, if attention is otherwise distracted. In the 1980s and 1990s, Arien Mack and Irvin Rock followed up on Neisser's work, developing a simple paradigm for examining how, when, and why distracted attention can make people fail to see the whole object. Their experiments, and Neisser's, did not involve people with brain damage, disease, or anything of the sort, just regular people who failed to see objects that were right in front of them. This phenomenon has been called inattentional blindness. This video will demonstrate basic procedures for investigating inattentional blindness using the methods of Mack and Rock.1

Investigating Visual Awareness and Inattentional Blindness

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
We generally think that we see things pretty well if they are close by and right in ...

Sensation and Perception

The Attentional Blink

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
In order for recognition of a certain stimulus to take place, visual attention needs to be directed towards said stimulus. To the earliest parts of the visual system, objects are not objects, they are collections of visual features-lines, corners, changes in texture, color, and light. Attention is the resource that is necessary for later processing in order to recognize what a given bundle of features adds up to. This makes attention a central focus of research. One especially important set of questions concerns how people sustain attention, that is, the extent to which they can continuously maintain a focus of attention from moment-to-moment. It is now known that sustained attention takes great effort. When attention needs to be focused very rapidly on something that is moving or changing very quickly, the effort involved causes a momentary lapse in attention once it is disengaged. This kind of lapse in attention is called an attentional blink. It is like the brain blinks for a moment, shutting down attention for a rest. Stimuli that appear during an attentional blink will not be perceived. 
In 1992, a group of researchers devised a paradigm to study the attentional blink, and the paradigm has come to be known by the same name.1 It demonstrates some of the challenges to maintaining focused attention. This video demonstrates how to implement the attentional blink paradigm in order to study sustained visual attention.

Sustained Visual Attention and the Attentional Blink Paradigm

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
In order for recognition of a certain stimulus to take place, visual attention ...