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 task.
<ol>
	<li>Choose trial types (i.e., Target Alone, Same Target Colored distraction, and Different Target Colored distraction as well as either or both of Distractor Alone and Non Target Colored distraction), and the preferred number of trials within each trial type7,20.</li>
	<li>Choose the target-distractor lag lengths in each trial type that contains distractors and targets (e.g., lags 1, 2, 3, and 4, or just lags 1 and 4, etc.)</li>
	<li>Choose colors for the letters - target colors, peripheral distractor colors, and central filler colors; there must be at least two target colors. Ensure that target colors are separated in color space by at least one &#34;filler&#34; color that appears in the central RSVP. See Figure 2 for example stimulus colors.</li>
	<li>Program the task using a flexible and reliable stimulus presentation software package (e.g., Psychtoolbox implemented in MATLAB39). 
	NOTE: Refer to software tutorials to learn about how to create stimulus presentations and collect responses.</li>
	<li>Ensure that the letter stimuli subtend 2.07 x 1.88 degrees of visual angle and are written in Arial font. Display the peripheral letters 4.22 degrees of visual angle to the right and left of the central letter.</li>
	<li>Present each frame of the display for 116 ms. 
	NOTE: There are three letters per frame display: the central letter and two peripheral letters.</li>
	<li>Other than when a target appears, assign &#34;filler&#34; colors to the letters in the central RSVP (see Figure 1). Assign these colors randomly, with the caveat that no two letters appearing adjacently in time in the RSVP sequence have the same color.</li>
	<li>Other than when a colored peripheral distractor appears, assign the color grey to the letters in the peripheral locations.</li>
	<li>Collect keyboard responses for 1740 ms following every trial.</li>
	<li>Randomize the order of all of the trials throughout the experiment.</li>
	<li>Include a two-part practice session at the start of the experiment that eases participants into the task and exposes them to all of the trial types.
	<ol>
		<li>In the first part, include at least 16 Target Alone trials, presented in all target colors with even representation of each color.</li>
		<li>Remind participants of the to-be-searched target colors by including color patches of these colors that appear just above the RSVP display and keep them fixed throughout the first part of practice.</li>
		<li>Start the practice at a slower RSVP speed, 250 ms per frame. Increase the speed (decrease the frame rate) by 10 ms every time a target is presented until reaching the final experiment speed.</li>
		<li>In the second part, remove the color patches and introduce trial types with peripheral distractors. Include at least 12 trials in total, and ensure that all trial types are presented at least once.</li>
	</ol>
	</li>
	<li>Provide participants with self-paced breaks every minute. After 32 trials, halt the continuous RSVP sequence and display a screen that says, &#34;Please take a break. Press the space bar to continue.&#34; On this screen, remind participants of the colors they are seeking. Present this text: &#34;As a reminder, these are your target colors:&#34; and follow it with &#34;ABCXYZ&#34; written in each target color.</li>
</ol>
2. Set up the Apparatus
<ol>
	<li>Use a computer with a 60 Hz refresh rate and a monitor and graphics card combination that provides millisecond precision of timing (see the Table of Materials).</li>
	<li>Ensure that the keyboard, monitor, and participant chair are in a fixed location, as proper and consistent spacing from the participant to the computer screen is important. If using a shared space, use masking tape to mark desired locations of equipment on the desk/table.</li>
</ol>
3. Recruit participants for the experiment.
<ol>
	<li>Recruit participants who are 18 - 35 years of age, free of neurological conditions, have corrected to normal vision, and are not colorblind.</li>
	<li>Perform a power calculation using previously published results and/or pilot participants in order to determine the appropriate sample size.40,41</li>
</ol>
4. Test the participants
<ol>
	<li>Obtain necessary consent according to the authorizing review board&#39;s policies.</li>
	<li>Seat the participants at a distance of 57 cm from the monitor, at which distance 1 cm on the screen corresponds to 1 degree of visual angle. Enforce this viewing distance with the use of a chin rest or with experimenter supervision.</li>
	<li>Check for colorblindness, by asking the participant completing an online colorblindness test42. Do not analyze data from a participant who is deemed colorblind.</li>
	<li>Open the software, navigate to the experiment folder, and type the experiment script (designed based upon the guidelines from section 1) into the command window and press enter; the program will run.</li>
	<li>Help the participant through the instructions, which are printed on a series of screens and can be read in a self-paced fashion. In addition to reading the instructions on the screen, state the following: &#34;This task is very difficult, with performance averaging about 75% correct. Do not be discouraged if you feel you are making many mistakes.)&#34;</li>
	<li>Supervise the participant during the experiment to ensure that he/she maintains a uniform viewing distance from the monitor, is completing the task properly (e.g., using the correct response keys used), and is not falling asleep or becoming distracted.</li>
	<li>Provide feedback and encouragement during the practice session.
	<ol>
		<li>Remind the participants of the key responses. Tell them, &#34;Remember, the &#34;J&#34; response key is for any target letter coming from the first half of the alphabet, and the &#34;K&#34; response key is for any target letter coming from the second half of the alphabet. Do not press &#34;J&#34; for one target color and &#34;K&#34; for the other.&#34;</li>
		<li>Remind participants to slow down and consider which response to make after identifying a letter, and that the response well be recorded as &#34;correct&#34; even if it does not occur immediately.</li>
	</ol>
	</li>
	<li>When the program concludes, debrief and dismiss the participant. Explain the purpose of the experiment and answer questions. Ask if the participant had any difficulties with the experiment or with completing the task.</li>
</ol>

The authors have nothing to disclose.

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.

<table><tbody><tr><td>MATLAB</td><td>Mathworks</td><td>R2014b</td><td>General computing platform</td></tr><tr><td>Psychtoolbox</td><td>Psychtoolbox</td><td>PTB-3</td><td>Toolbox of routines for use with MATLAB</td></tr><tr><td>G*Power</td><td>Universit&amp;auml;t D&amp;uuml;sseldorf</td><td>G*Power 3.1.9.2 for Windows</td><td>Software to assist with performing power calculations</td></tr><tr><td>24&amp;rdquo; HDMI Gaming Monitor</td><td>ASUS</td><td>VG248QE</td><td>High quality LCD monitor with excellent timing</td></tr></tbody></table>

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. ...

using-rapid-serial-visual-presentation-to-measure-set-specific

Universidad de Cartagena UDEC

Research

JoVE Journal

Behavior

8.8K Views.  Arcadia University. This method uses a dynamic visual display to index costs of distraction during visual search, including both "contingent attentional capture" and "set-specific capture," 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.

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

Automated Visual Cognitive Tasks for Recording Neural Activity Using a Floor Projection Maze

Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have developed visual cognitive tasks for rats using the Floor Projection Maze1,2&#160;that are optimized for visual abilities of rats permitting stronger comparisons of experimental findings with other species.
In order to investigate neural correlates of learning and memory, we have integrated electrophysiological recordings into fully automated cognitive tasks on the Floor Projection Maze1,2. Behavioral software interfaced with an animal tracking system allows monitoring of the animal's behavior with precise control of image presentation and reward contingencies for better trained animals. Integration with an in vivo electrophysiological recording system enables examination of behavioral correlates of neural activity at selected epochs of a given cognitive task.
We describe protocols for a model system that combines automated visual presentation of information to rodents and intracranial reward with electrophysiological approaches. Our model system offers a sophisticated set of tools as a framework for other cognitive tasks to better isolate and identify specific mechanisms contributing to particular cognitive processes.

We describe protocols for training rats for chronic electrophysiological recordings in fully automated cognitive tasks on a Floor Projection Maze.

Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have ...

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;

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 ...

Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments

This protocol describes how to conduct temporal-order experiments to measure visual processing speed and the attentional resource distribution. The proposed method is based on a new and synergistic combination of three components: the temporal-order judgments (TOJ) paradigm, Bundesen&#39;s Theory of Visual Attention (TVA), and a hierarchical Bayesian estimation framework. The method provides readily interpretable parameters, which are supported by the theoretical and neurophysiological underpinnings of TVA. Using TOJs, TVA-based estimates can be obtained for a broad range of stimuli, whereas traditional paradigms used with TVA are mainly limited to letters and digits. Finally, the meaningful parameters of the proposed model allow for the establishment of a hierarchical Bayesian model. Such a statistical model allows assessing results in one coherent analysis both on the subject and the group level.
To demonstrate the feasibility and versatility of this new approach, three experiments are reported with attention manipulations in synthetic pop-out displays, natural images, and a cued letter-report paradigm.

Temporal-order judgments can be used to estimate processing speed parameters and attentional weights and thereby to infer the mechanisms of attentional processing. This methodology can be applied to a wide range of visual stimuli and works with many attention manipulations.

This protocol describes how to conduct temporal-order experiments to measure visual processing speed and the attentional resource distribution. The ...

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 ...

Simultaneous Monitoring of Wireless Electrophysiology and Memory Behavioral Test as a Tool to Study Hippocampal Neurogenesis

Brainwaves amplitude obtained from electroencephalography (EEG) has been well-recognized as a basis for cognitive capacity, memory, and learning on animals and humans. Adult neurogenesis mechanism is also linked to memory and learning improvement. Traditionally, researchers used to assess learning and memory parameters in rodent models by behavioral tasks. Therefore, the simultaneous monitoring of behavioral changes and EEG is particularly interesting in correlating data between brain activity and task-related behaviors. However, most of the equipment required to perform both studies are either complex, expensive, or uses a wired setup network that hinders the natural animals&#8217; movement. In this study, EEG was recorded with a wireless electrophysiology device along with the execution of a novel object recognition task (NORT). The animal&#8217;s behavior was monitored simultaneously by a video tracking system. Both recordings were analyzed offline by their timestamps which were synched to link EEG signals with the animal&#8217;s actions. Subjects consist of adult Wistar rats after medium-term environmental enrichment treatment. Six skull screw electrodes were fixed in pairs on both hemispheres over frontal, central, and parietal regions and were referenced to an electrode located posterior of the nasal bone. NORT protocol consists of exposing the animal to two identical objects for 10 min. After 2 h and 24 h, one of the objects was replaced with a novel one. Exploration time for each object was monitored by a behavioral tracking software (BTS) and EEG data recording. The analysis of the EEG synced with behavioral data consists of estimations of alpha and beta relative band power and comparisons between novel object recognition versus familiar object exploration, between three experimental stages. In this manuscript, we have discussed electrodes manufacturing process, epidural electrodes implantation surgery, environmental enrichment protocol, NORT protocol, BTS setup, EEG &#8211; BTS coupling for simultaneous monitoring in real-time, and EEG data analysis based on automatic events detection.

The protocol presented here provides information on the simultaneous electroencephalography (EEG) and behavioral assessment in real-time. We have discussed all steps involved in this protocol as an attractive solution for researchers in many fields of neuroscience, particularly in learning and memory areas.

Brainwaves amplitude obtained from electroencephalography (EEG) has been well-recognized as a basis for cognitive capacity, memory, and learning on ...

Integrating VR and Biosensors for Quantitative Motion-Muscle Activity Assessment

Setup for the Quantitative Assessment of Motion and Muscle Activity During a Virtual Modified Box and Block Test

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and independence and may lead to complications. The importance of remote patient evaluation and rehabilitation has recently grown due to limited access to in-person services. For example, the COVID-19 pandemic unexpectedly resulted in strict regulations, reducing access to non-emergent healthcare services. Additionally, remote care offers an opportunity to address healthcare disparities in rural, underserved, and low-income areas where access to services remains limited. 
Improving accessibility through remote care options would limit the number of hospital or specialist visits and render routine care more affordable. Finally, the use of readily available commercial consumer electronics for at-home care can enhance patient outcomes due to improved quantitative observation of symptoms, treatment efficacy, and therapy dosage. While remote care is a promising means to address these issues, there is a crucial need to quantitatively characterize motor impairment for such applications. The following protocol seeks to address this knowledge gap to enable clinicians and researchers to obtain high-resolution data on complex movement and underlying muscle activity. The ultimate goal is to develop a protocol for remote administration of functional clinical tests. 
Here, participants were instructed to perform a medically-inspired Box and Block task (BBT), which is frequently used to assess hand function. This task requires subjects to transport standardized cubes between two compartments separated by a barrier. We implemented a modified BBT in virtual reality to demonstrate the potential of developing remote assessment protocols. Muscle activation was captured for each subject using surface electromyography. This protocol allowed for the acquisition of high-quality data to better characterize movement impairment in a detailed and quantitative manner. Ultimately, these data have the potential to be used to develop protocols for virtual rehabilitation and remote patient monitoring.

Author Spotlight: Enhancing Remote Rehabilitation with Virtual Reality and Electromyography

The protocol described here aims to enhance the quantitative evaluation of upper limb deficits, with the goal of developing additional technology for remote assessment both in the clinic and at home. Virtual reality and biosensor technologies are combined with standard clinical techniques to provide insights into the functioning of the neuromuscular system.

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and ...

Engineering

Touchscreen Sustained Attention Task (SAT) for Rats

Sustained attention is the ability to monitor intermittent and unpredictable events over a prolonged period of time. This attentional process subserves other aspects of cognition and is disrupted in certain neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. Thus, it is clinically important to identify mechanisms that impair and improve sustained attention. Such mechanisms are often first discovered using rodent models. Therefore, several behavior procedures for testing aspects of sustained attention have been developed for rodents. One, first described by McGaughy and Sarter (1995), called the sustained attention task (SAT), trains rats to distinguish between signal (i.e., brief light presentation) and non-signal trials. The signals are short and thus require careful attention to be perceived. Attentional demands can be increased further by introducing a distractor (e.g., flashing houselight). We have modified this task for touchscreen operant chambers, which are configured with a touchscreen on one wall that can present stimuli and record responses. Here we detail our protocol for SAT in touchscreen chambers. Additionally, we present standard measures of performance in male and female Sprague-Dawley rats. Comparable performance on this task in both sexes highlights its use for attention studies, especially as more researchers are including female rodents in their experimental design. Moreover, the easy implementation of SAT for the increasingly popular touchscreen chambers increases its utility.

Touchscreen Sustained Attention Task SAT for Rats

Sustained attention, or continuously monitoring situations for intermittent and unpredictable events, is a critical aspect of cognition. Here we detail how to test sustained attention in rats using touchscreen operant chambers. We demonstrate comparable performance in male and female rats, making this task useful for studying attention in both sexes.

Sustained attention is the ability to monitor intermittent and unpredictable events over a prolonged period of time. This attentional process subserves ...

Neuroscience

Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined curved surfaces, and images of real-world objects (with and without disparity) in a similar manner as described in the ventral visual stream. In addition, parieto-frontal areas are believed to convert visual object information into appropriate motor outputs, such as the pre-shaping of the hand during grasping. To better characterize object selectivity in the cortical network involved in visuomotor transformations, we provide a battery of tests intended to analyze the visual object selectivity of neurons in parieto-frontal regions.

A detailed protocol to analyze object selectivity of parieto-frontal neurons involved in visuomotor transformations is presented.

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined ...

Automated Multimodal Stimulation and Simultaneous Neuronal Recording from Multiple Small Organisms

Fluorescent genetically encoded calcium indicators have contributed greatly to our understanding of neural dynamics from the level of individual neurons to entire brain circuits. However, neural responses may vary due to prior experience, internal states, or stochastic factors, thus generating the need for methods that can assess neural function across many individuals at once. Whereas most recording techniques examine a single animal at a time, we describe the use of wide-field microscopy to scale up neuronal recordings to dozens of Caenorhabditis elegans or other sub-millimeter-scale organisms at once. Open-source hardware and software allow great flexibility in programming fully automated experiments that control the intensity and timing of various stimulus types, including chemical, optical, mechanical, thermal, and electromagnetic stimuli. In particular, microfluidic flow devices provide precise, repeatable, and quantitative control of chemosensory stimuli with sub-second time resolution. The NeuroTracker semi-automated data analysis pipeline then extracts individual and population-wide neural responses to uncover functional changes in neural excitability and dynamics. This paper presents examples of measuring neuronal adaptation, temporal inhibition, and stimulus crosstalk. These techniques increase the precision and repeatability of stimulation, allow the exploration of population variability, and are generalizable to other dynamic fluorescent signals in small biosystems from cells and organoids to whole organisms and plants.

We present a method for the flexible chemical and multimodal stimulation and recording of simultaneous neural activity from many Caenorhabditis elegans worms. This method uses microfluidics, open-source hardware and software, and supervised automated data analysis to enable the measurement of neuronal phenomena such as adaptation, temporal inhibition, and stimulus crosstalk.

Fluorescent genetically encoded calcium indicators have contributed greatly to our understanding of neural dynamics from the level of individual neurons ...

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 ...