We would like to thank Ms. Isabelle Booth, a Colorado State University honors student who assisted with accelerometry data analysis. We would also like to acknowledge funding from NIH K12 HD055931 and K01 HD096047-02 issued to author J.S.

All study procedures were approved by the Institutional Review Board (IRB) at Colorado State University, and all adult participants provided written informed consent prior to completing any study procedures. Written informed consent was provided by parents of participants under 18, and minor participants also provided written assent prior to completing any study procedures.
1. Revised Dual Task Screen (DTS)
<ol>
	<li>Lower Extremity (LE) Subtask
	<ol>
		<li>Start the single motor condition.
		<ol>
			<li>Place three yoga blocks in a horizontal position exactly 4.5 m apart along an 18 m walkway.</li>
			<li>Firmly attach smart devices to each ankle to detect heel strikes and obtain gait characteristics.</li>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Instruct participants to walk as quickly as possible while stepping over obstacles. Start data collection on the smartphones and sharply tap the devices simultaneously for subsequent time alignment of the two separate data streams from the left and right legs.&#160;</li>
			<li>Measure the time-to-complete with a hand-operated stopwatch.</li>
			<li>Stop video recording.</li>
		</ol>
		</li>
		<li>Start the single cognitive condition.
		<ol>
			<li>Tell the participant his/her allocated time for this condition, using the time-to-complete from his/her single motor condition (rounding up to a full second).</li>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Instruct participants to state as many words as they can that begin with a particular letter (A or F). 
			NOTE: Letters are counter-balanced between participants and between the single and dual task conditions. Numbers are counter-balanced between participants and between the single and dual task conditions.</li>
			<li>Stop video recording.</li>
		</ol>
		</li>
		<li>Start the dual task condition.
		<ol>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Instruct participants to walk as quickly as possible while stepping over obstacles while simultaneously stating as many words as they can that begin with a particular letter (A or F). Rapidly tap&#160;both accelerometers to start the condition.</li>
			<li>Measure the time-to-complete with a hand-operated stopwatch.</li>
			<li>Stop video recording.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Upper Extremity (UE) subtask
	<ol>
		<li>Start the single motor condition.
		<ol>
			<li>Measure a distance of 1.5 m away from a wall, mark with masking tape, and instruct the participant to stand behind the tape.</li>
			<li>Place a basket of tennis balls next to the participant.</li>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Instruct the participant to complete a wall-toss with alternating hands for 30 s. Tell the participant that if he/she fails to catch a ball, to acquire a new ball from the basket of tennis balls. Measure time elapsed with a stopwatch.</li>
			<li>Stop video recording.</li>
		</ol>
		</li>
		<li>Start the single cognitive condition.
		<ol>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Tell the participant that he/she will be asked to sequentially subtract by 7 from a given number (100 or 150) for 30 seconds. Measure time elapsed with a stopwatch.</li>
			<li>Stop video recording. 
			NOTE: Letters are counter-balanced between participants and between the single and dual task conditions. Numbers are counter-balanced between participants and between the single and dual task conditions.</li>
		</ol>
		</li>
		<li>Start the dual task condition.
		<ol>
			<li>Ask the participant to stand 1.5 m away from a wall.</li>
			<li>Place a basket of tennis balls next to participant.</li>
			<li>Begin video recording with a camcorder on a tripod.</li>
			<li>Instruct the participant to complete a wall-toss with alternating hands for 30 seconds. Inform the participant that, while throwing and catching the balls, he/she will be asked to sequentially subtract by 7 from a given number (100 or 150) for 30 seconds. Tell the participant that if he/she fails to catch a ball, to acquire a new ball from the basket of tennis balls. Measure time elapsed with a stopwatch.</li>
			<li>Stop video recording. 
			NOTE: Letters are counter-balanced between participants and between the single and dual task conditions. Numbers are counter-balanced between participants and between the single and dual task conditions.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
2. Neuroimaging-Compatible Dual Task Screen (DTS)
<ol>
	<li>Set up the DTS
	<ol>
		<li>Place yoga blocks in a vertical position to mark the start and end of a 15 m walkway.</li>
		<li>Place two yoga blocks in a horizontal position exactly 5 m apart along the 15 m walkway.</li>
		<li>Measure and mark with masking tape a distance 1.5 m away from a smooth wall surface.</li>
		<li>Set up a tripod at the beginning of the 15 m walkway.</li>
	</ol>
	</li>
	<li>Place the fNIRS device on participant&#8217;s head.
	<ol>
		<li>Measure the participant&#8217;s head circumference and select appropriately sized fNIRS cap (Table of Materials) with pre-placed optodes and short-channel detectors.</li>
		<li>Turn on a dedicated acquisition laptop and connect to the fNIRS device&#8217;s WiFi network.</li>
		<li>Open the fNIRS acquisition software and select the fNIRS device.</li>
		<li>Perform calibration to optimize light intensity and check optode signal levels. Signal levels should be acceptable or excellent.</li>
		<li>Fix all optodes with less than acceptable signal level by removing the optode from the cap and parting the participant&#8217;s hair to ensure a direct connection of the optode to the participant&#8217;s scalp.</li>
	</ol>
	</li>
	<li>Place accelerometers on the participant&#8217;s ankles.
	<ol>
		<li>Firmly attach smart devices to each ankle to detect heel strikes and obtain gait characteristics.</li>
	</ol>
	</li>
	<li>Begin LE subtask data acquisition.
	<ol>
		<li>Open the stimulus presentation software (Table of Materials).</li>
		<li>Select the LE subtask file.</li>
		<li>Ask the participant to sit in a chair in preparation for a 60 s quiet rest period.</li>
		<li>Return to the fNIRS acquisition software and click the Start button to begin collecting fNIRS data. Enter subject ID_LE, age, and sex into the pop-up window and click Start.</li>
		<li>Return to the stimulus presentation software, inform the participant that quiet rest will begin, and press Space to start the 60 s rest period.</li>
		<li>At the end of the rest period, identify which LE Subtask condition (single motor, single cognitive, or dual task) has been selected for the 1st trial. Provide participant with instructions for that trial.
		<ol>
			<li>Single Motor Instructions: Instruct the participant to walk as quickly as possible, while stepping over the obstacles, for 30 s. Tell participant that he/she will start when the primary researcher says &#8220;Start&#8221;. This will occur immediately after a secondary researcher taps the accelerometers. Instruct the participant that he/she should stop walking when the primary researcher says &#8220;stop.&#8221; Additionally, when the primary researcher says &#8220;stop,&#8221; the participant should put his/her feet together and remain as still as possible. At this time, the secondary researcher will tap the accelerometers a second time and place a marker (sticky note) on the floor where the participant stopped.</li>
			<li>Single Cognitive Instructions: Instruct the participant to remain standing at the start of the 15 m walkway. While standing, he/she will be asked to state as many words as possible that begin with a particular letter.</li>
			<li>Dual Task Instructions: Instruct the participant to walk as quickly as possible while stepping over the obstacles and simultaneously stating as many words as possible beginning with a particular letter. Inform him/her that he/she will also have 30 seconds for this condition. Tell participant that he/she will start when the primary researcher says &#8220;start&#8221;. This will occur immediately after a secondary researcher taps the accelerometers. Instruct the participant that he/she should stop walking when the primary researcher says &#8220;stop.&#8221; Additionally, when the primary researcher says &#8220;stop,&#8221; the participant should put his/her feet together and remain as still as possible. At this time, the secondary researcher will tap the accelerometers a second time and place a marker (sticky note) on the floor where the participant stopped.</li>
		</ol>
		</li>
		<li>Begin video recording with a camcorder on a tripod.</li>
		<li>Press the Space bar to start the 1st trial. Monitor the 30 s timer on the stimulus presentation software; tell the participant to stop when 30 s have elapsed.</li>
		<li>Identify the 2nd trial and provide the participant with instructions. Repeat the process until the participant has completed 15 randomized trials of the LE Subtask.</li>
		<li>Stop video recording.</li>
		<li>Inform the participant that he/she will complete another 60 s seated rest period. Once the participant is seated, press Start to begin the rest period.</li>
		<li>Following the rest period, exit out of the LE subtask file in the stimulus presentation software. Stop data acquisition in fNIRS data acquisition software, but do not exit the software. 
		NOTE: Letters are randomized (by the stimulus presentation software) between trials and counter-balanced between participants and between single and dual task conditions. Letters are similar in level of difficulty and include: W, D, F, T, S, H, M, A, B, and P. Numbers are randomized (by the stimulus presentation software) between trials and counter-balanced between participants and between single and dual task conditions. Numbers included: 185, 225, 220, 175, 205, 165, 170, 180, 245, and 240.</li>
	</ol>
	</li>
	<li>Remove accelerometers from the participant&#8217;s ankles. Move to the section in the hallway designated for the UE Subtask.</li>
	<li>Begin UE subtask data acquisition.
	<ol>
		<li>Open the stimulus presentation software.</li>
		<li>Select the UE subtask file.</li>
		<li>Ask the participant to sit in a chair in preparation for a 60 s quiet rest period.</li>
		<li>Return to the fNIRS acquisition software and click the Start button to begin collecting fNIRS data. Enter subject ID_UE, age, and sex into the pop-up window and click start.</li>
		<li>Return to the stimulus presentation software, inform the participant that the quiet rest period is about to begin, and press Space to start 60 s rest period.</li>
		<li>At the end of the rest period, identify which UE Subtask condition (single motor, single cognitive, or dual task) has been selected for the 1st trial. Provide the participant with instructions for that trial.
		<ol>
			<li>Single Motor Instructions: Instruct the participant to stand 1.5 m away from a wall. Place a basket of tennis balls next to participant. Instruct the participant to complete a wall-toss with alternating hands for 30 s. Tell the participant that if he/she fails to catch a ball, to acquire a new ball from the basket of tennis balls.</li>
			<li>Single Cognitive Instructions: Instruct the participant to remain standing Tell the participant that he/she will be asked to sequentially subtract by 7 from a given number for 30 s.</li>
			<li>Dual Task Instructions: Instruct the participant to complete a wall-toss with alternating hands for 30 s. Inform the participant that, while throwing and catching the balls, he/she will be asked to sequentially subtract by 7 from a given number2 for 30 s. Tell the participant that if he/she fails to catch a ball, to acquire a new ball from the basket of tennis balls.</li>
		</ol>
		</li>
		<li>Begin video recording with a camcorder on a tripod.</li>
		<li>Press the Space bar to start the 1st trial. Monitor the 30 s timer on the stimulus presentation software; tell participant to stop when 30 s have elapsed.</li>
		<li>Identify the 2nd trial and provide the participant with instructions. Repeat the process until participant has completed 15 randomized trials of the UE Subtask.</li>
		<li>Stop video recording.</li>
		<li>Inform the participant that he/she will complete another 60 s seated rest period. Once the participant is seated, press Start to begin the rest period.</li>
		<li>Following the rest period, exit out of the UE Subtask file in the stimulus presentation software. Stop the data acquisition in fNIRS data acquisition software, and then exit the software.</li>
	</ol>
	</li>
	<li>Remove fNIRS cap from participant&#8217;s head. 
	NOTE: Letters are randomized (by the stimulus presentation software) between trials and counter-balanced between participants and between single and dual task conditions. Letters are similar in level of difficulty and include: W, D, F, T, S, H, M, A, B, and P. Numbers are randomized (by the stimulus presentation software) between trials and counter-balanced between participants and between single and dual task conditions. Numbers included: 185, 225, 220, 175, 205, 165, 170, 180, 245, and 240.</li>
</ol>

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The authors have no conflicts of interest to disclose.

In this manuscript, we described the administration protocol for the newly revised Dual Task Screen (DTS). These revisions were completed to address limitations identified in the original DTS15 and included the addition of single cognitive conditions to test for dual task cognitive costs. It also included smart-device based accelerometry to more precisely measure gait characteristics. We included representative results which illustrate the type of clinical data that can be acquired with the DTS. W...

Each year, 42 million people worldwide sustain mild traumatic brain injuries (mTBIs)1. Although once considered benign, new research indicates that mTBIs, particularly repeat mTBIs, can elicit lasting negative consequences, such as physical, cognitive, and sleep disturbances2,3,4. Subsequently, researchers and clinicians are seeking enhanced evaluations and treatment methods to understand and address mTBI.
To date, best practice for mTBI evaluation includes self-reported symptoms and objective measurement of neurocognitive and motor function5. However, some individuals, like competitive collegiate-level athletes, are known to underreport mTBI-related symptoms6, limiting the utility of symptom reports. Objective neurocognitive and motor function measures also have limitations, including poor test-retest reliability, reliance on baseline testing, or insufficient difficulty for high-performing athletes7,8,9. However, dual task paradigms - which simultaneously assess motor and cognitive abilities - can detect subtle, residual impairments and may be particularly useful for evaluating high-performing athletes10,11,12,13,14.
Past research using dual task paradigms have often incorporated cumbersome, expensive laboratory equipment, such as motion capture systems14, to evaluate high-performing athletes. While these systems can accurately measure subtle motor impairments, they are impractical for use in everyday mTBI evaluation due to high equipment cost, limited portability, and long administration times (i.e., &#8805; 45 minutes per individual). Further, many past dual task paradigm studies focused solely on lower body or lower extremity skills, such as balance or gait11,12,13,14. Arguably, upper extremity function and hand-eye coordination is also important for high-performing athletes in many sports. Thus, we developed the Dual Task Screen (DTS), which is a brief measure designed to be administered and scored in &#60;10 minutes with portable, low-cost instruments. This original DTS included a lower extremity (LE) and upper extremity (UE) subtask, which evaluated gait speed (using a stopwatch) and hand-eye coordination under single motor and dual task conditions15.
In the first feasibility study, 32 healthy, female adolescent participants completed the original DTS. This study was designed to establish that the DTS could elicit dual task motor costs, as indicated by reduced motor performance during dual task vs. single motor conditions. We also sought to establish that the DTS could be administered and scored in fewer than 10 minutes. We found that all participants had poorer dual task motor performance on at least one subtask. Additionally, we were able to administer the DTS in an average of 5.63 minutes and score the test in 2-3 minutes15.
Although the first feasibility study was successful, a few limitations were revealed. Most notably, gait speed was measured with stopwatches, which are prone to natural human error. Therefore, in the revised DTS we used smart devices with built-in accelerometers (Table of Materials) on each ankle. This addition maintained the use of portable, low-cost instruments while still providing sophisticated measures of gait speed, total number of steps, average step length, average step duration, and step duration variability. Another limitation of the original DTS was the absence of single cognitive conditions, which prevented evaluation of dual task cognitive costs. Dual task cognitive costs are defined as poorer cognitive performance during the dual task vs. single cognitive condition. Subsequently, for both the LE and UE subtasks, we added a single cognitive condition (described in Protocol).
In addition to developing a measure for future clinical use, one of the team&#8217;s long-term goals is to evaluate the neural underpinnings of single and dual task performance in healthy athletes and contrast those findings to athletes with sports-induced mTBI. Thus, we have created a neuroimaging-compatible version of the DTS. We seek to determine if the DTS can be successfully modified for use with simultaneous functional near-infrared spectroscopy (fNIRS) measurement, and we are using a mobile fNIRS device specifically designed to accommodate gross-motor movement by reducing the influence of motion artifacts. Further, this device has the greatest amount of head coverage, to our knowledge, for mobile devices that are currently available for research purposes (Table of Materials).
In summary, the study protocol is designed to do the following:
<ol>
	<li>Describe the administration protocol for the revised Dual Task Screen (DTS), which is a measure we redesigned to address the limitations of the original DTS15 and a measure intended for future clinical use.</li>
	<li>Describe the research protocol for the neuroimaging-compatible Dual Task Screen (DTS), which we have designed to evaluate the neural underpinnings of single and dual task performance.</li>
</ol>

<table><tbody><tr><td>&lt;strong&gt;Hardware (in alphabetical order)&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>NIRx NIRSport2 Device: NSP2-CORE1616</td><td>NIRx</td><td>Reference #: GC359</td><td>&quot;The NIRSport 2 is a user-friendly, modular, and robust wireless functional near-infrared spectroscopy (fNIRS) platform which measures hemodynamic responses to neuroactivation via oxy-, deoxy-, and total hemoglobin changes in the cerebral cortex.The NIRSport 2 comes with a host of ready-to-implement upgrades and modules to meet the needs of a broad range of cognitive neuroscience applications.&quot; (Direct quote from nirx.net/nirsport)</td></tr><tr><td>NIRx NIRSCap (available in 5 difference sizes)</td><td>NIRx</td><td>N/A</td><td>&quot;The NIRScap consists of a measuring cap and optode holders. The optode holders fit into the slits of the measuring cap.&quot; (Direct quote from NIRx&#039;s NIRScap Getting Started Guide)</td></tr><tr><td>NIRx Optode Sources (x 2)</td><td>NIRx</td><td>Reference #: GC359</td><td>&quot;8-source active source bundel for fiberless optical illumination with dual tip; 240 cm long.&quot; (Direct quote from NIRx Packing List Description)</td></tr><tr><td>NIRx Optode Detectors (x 2)</td><td>NIRx</td><td>Reference #: GC359</td><td>&quot;Bundle of 8x active sensores for fiberless optical detection; dual tip; 240 cm long.&quot; (Direct quote from NIRx Packing List Description)</td></tr><tr><td>NIRx Short Distance Detector Probes</td><td>NIRx</td><td>N/A</td><td>&quot;The probes come in a bundle of eight detector clips that allows coupling of short-distance data from eight independent sources sites to one common detector channel on the instrument.&quot; (Direct quote from NIRx&#039;s Short Distance Detector Probes Getting Started Guide)</td></tr><tr><td>&lt;strong&gt;Software (in alphabetical order)&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Aurora</td><td>NIRx</td><td>N/A</td><td>&quot;NIRSport 2 Acquistion Software. Aurora fNIRS connects to your NIRSport 2 device via Wi-Fi or USB and can set-up a complete experimental configuration in only several clicks. Thanks to the automated signal optimization algorithm, Aurora fNIRS ensures optimal signal quality before a measurement is started. Raw data, HbO and Hb concentration changtes can be visualized in real-time in several display modes. In addition, high-end whole head visualizations are immediately available. Recorded data can be exported over the integrate Lab Streaming Layer (LSL) protocol, allowing for real-time processing in Brain-Computer Interface (BCI) and Neurofeedback paradigms.&quot; (Direct quote from nirx.net/software)</td></tr><tr><td>Matlab</td><td>Math Works</td><td>N/A</td><td>&quot;MATLAB&amp;reg; combines a desktop environment tuned for iterative analysis and design processes with a programming language that expresses matrix and array mathematics directly. It includes the Live Editor for creating scripts that combine code, output, and formatted text in an executable notebook.&quot; (Direct quote from mathworks.com)</td></tr><tr><td>NIRS Toolbox</td><td>Developed by Huppert Brain Imaging Lab</td><td>N/A</td><td>&quot;NIRS toolbox is a Matlab based analysis program.&quot; (Direct quote from huppertlab.net/nirs-toolbox-2/)</td></tr><tr><td>PsychoPy</td><td>Python</td><td>N/A</td><td>&quot;PsychoPy is an open source software package written in the Python program,ming language primarily for us in neuroscience and experimntal psychology research.&quot; (Direct quote from psychopy.org)</td></tr><tr><td>&lt;strong&gt;Lower Tech/Cost Research Supplies* (in alphabetical order)&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>AmazonBasics 60-Inch Lightweight Tripod with Bag</td><td>Amazon</td><td>Item Model #: WT3540</td><td>This lightweight tripod is perfect for most cameras up to 6.6 pounds. Setup is quick and easy. The included bag makes storage and transport a snap.The tripod&amp;rsquo;s legs can extend from 20&amp;rdquo; to 48&amp;rdquo;. Leg locks release smoothly and glide easily to your desired height. Crank up the center post for a tripod that is 60&amp;rdquo; tall. (Direct quote from Amazon.com)</td></tr><tr><td>iPod Touch x 2</td><td>Apple</td><td>N/A</td><td>Smart device with built-in accelerometer.</td></tr><tr><td>Panasonic Full HD Video Camera Camcorder HC-V180K, 50X Optical Zoom, 1/5.8-Inch BSI Sensor, Touch Enabled 2.7-Inch LCD Display (Black)</td><td>Amazon</td><td>Item Model #: HC-V180K</td><td>Compact, lightweight and easy to use, the Panasonic Full HD Camcorder HC-V180K brings a fun, worry-free experience to high-resolution video capture. Featuring a 5-axis image stabilizer for maximum handheld stability, this 1080p camera&amp;rsquo;s super-long 50X optical zoom and up to 90X intelligent zoom quickly bring distant objects in focus. A convenient 28mm wide-angle lens allows you to fit more people and scenery into settings like weddings, reunions and vacations. An advanced BSI sensor assures low-light video image quality while Panasonic&amp;rsquo;s Level Shot function automatically detects and compensates for distracting camera tilting. For added fun, the camera includes creative filter effects like 8mm Movie, Silent Movie, Miniature Effect and Time Lapse Recording, all easily accessible on the 2.7-inch LCD touch screen. A two-channel zoom microphone works in tandem with the zoom to ensure crisp, clear audio up close or at any distance.&quot; (Direct quote from Amazon.com)</td></tr><tr><td>Post-it Notes, 3&quot; x 3&quot;, Canary Yellow, Pack Of 18 Pads</td><td>Office Depot/Office Max</td><td>Item # 1230652</td><td>&quot;Post it&amp;reg; Notes stick securely and remove cleanly, featuring a unique adhesive designed for use on paper.&quot;</td></tr><tr><td>Scotch 232 Masking Tape, 1&quot; x 60 Yd</td><td>Office Depot/Office Max</td><td>Item # 910588</td><td>&quot;High-performance paper masking tape produces sharp paint lines in medium-temperature paint bake operations. Scotch tape provides clean removal every time, even on traditionally difficult-to-remove surfaces.&quot; (Direct quote from officedepot.com)</td></tr><tr><td>Stanley Tools Leverlock Tape Measure, Standard, 25&#039; x 1&quot; Blade</td><td>Office Depot/Office Max</td><td>Item #389512</td><td>&quot;Tape rule features a power return with automatic bottom lock for easy operation. High-visibility case color makes it easy to find. Special Tru-Zero hook allows use of nail as pivot to draw circles and arcs. Tape rule offers a multiple riveted hook and polymer-coated blade for longer life, blade wear guard and comfortable rubber grip. Protected blade resists abrasion, oils, dirt and most solvents. Tape rule has Imperial ruling with consecutive feet on top and consecutive inches on bottom after the first foot. Its belt clip allows easy carrying.&quot; (Direct quote from officedepot.com)</td></tr><tr><td>Stopwatch</td><td>Office Depot/Office Max</td><td>Item # 357698</td><td>&quot;Offers split timing, precise to 1/100 of a second. Includes 6 functions &amp;mdash; hour, minute, second, day, month and year.&quot; (Direct quote from officedepot.com)</td></tr><tr><td>Tourna Ballport Deluxe Tennis Ball Hopper with Wheels - Holds 80 Balls</td><td>Amazon</td><td>Item Model #: BPD-80W</td><td>&quot;Balloon port 80 deluxe holds 80 balls and comes with wheels for easy Maneuverability. The handles are an extra long 33 inch for more convenient feed and pickup. Very lightweight yet durable makes this one of the most premium hoppers on the market. Loaded with patented features: legs lock in up and down position. Bars at the top slide closed so your the balls don&#039;t fall out during transport. Bars roll at the bottom so the ball slips in the hopper easily.&quot; (Direct quote from Amazon.com)</td></tr><tr><td>Tourna Pressureless Tennis Balls with Vinyl Tote (45 pack of balls)</td><td>Amazon</td><td>Item Model #: EPTB-45</td><td>&quot;45 Pressure less tennis balls in a vinyl tote bag. Bag has a zipper for secure closure. Balls are regulation size and durable. Suitable for practice or tennis ball machines. Balls are pressure less so they never go dead. Pressure-less means they never go dead, which makes them great for tennis practice, ball machines, filling up ball baskets and hoppers, or just making sure your pet has hours of fun chasing these balls. They fit Chuck-it style dog ball launchers and automatic ball launchers. Durable rubber and a premium felt ensures their use can be universal, whether your a budding tennis player or a pet owner.&quot; (Direct quote from Amazon.com)</td></tr><tr><td>Velcro</td><td>Velcro</td><td>N/A</td><td>Self-adhesive strips and wraps; used to secure smart devices.</td></tr><tr><td>Yoga Block 2 Pack &amp;ndash; 2 High Density Light Weight Exercise Blocks 4 x 6 x 9 Inches Support All Poses - Lightweight Versatile Fitness and Balance Odor Free Bricks (Note: 6 blocks are needed for Dual Task Screen)</td><td>Amazon</td><td>N/A</td><td>&quot;These blocks are made from recycled high density EVA foam and provide firm support in a wide range of different yoga poses. This will improve your posture and you can stay in challenging poses for longer.&quot; (Direct quote from Amazon.com)</td></tr><tr><td>&lt;em&gt;*These items or comparable items can be obtained from a number of other sources&lt;/em&gt;</td><td></td><td></td><td></td></tr></tbody></table>

revised and neuroimaging-compatible versions of the dual task screen

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild traumatic brain injury (mTBI). However, past dual task paradigms have focused solely on lower extremity skills and have relied on cumbersome, expensive laboratory equipment - thus limiting their practicality for everyday mTBI evaluation. Subsequently, we developed the Dual Task Screen (DTS), which takes &#60;10 minutes to administer and score, uses low-cost portable equipment, and includes lower extremity (LE) and upper extremity (UE) subtasks. The purpose of this manuscript was twofold. First, we describe the administration protocol for the revised DTS, which we revised to address the limitations of the original DTS. Specifically, the revisions included additions of smart devices to acquire more detailed gait data and inclusion of single cognitive conditions to test for disrupted cognitive performance under dual task conditions. Importantly, the revised DTS is a measure intended for future clinical use, and we present representative results from three male athletes to illustrate the type of clinical data that can be acquired from the measure. Importantly, we have yet to evaluate the sensitivity and specificity of the revised DTS in athletes with mTBI, which is the next research initiative. The second purpose of this manuscript is to describe a neuroimaging-compatible version of the DTS. We developed this version so we could evaluate the neural underpinnings of single and dual task performance, for a better empirical understanding of the behavioral deficits associated with mTBI. Thus, this manuscript also describes the steps we took to enable simultaneous functional near-infrared spectroscopy (fNIRS) measurement during the DTS, along with how we acquired and completed first-level processing of the fNIRS data.

Participants 
Participants were recruited from local high school teams and university intercollegiate and club sports teams using word-of-mouth and advertising flyers. Participants were required to be between the ages of 15-22 and engage in regular participation in organized contact sports. Contact sports included all sports where physical contact with teammates or opponents is necessary during routine play. Participants also had to have normal or corrected vision and hearing, no history of neurolog...

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Revised and Neuroimaging-Compatible Versions of the Dual Task Screen

We developed the original Dual Task Screen (DTS) as a portable, low-cost measure that can evaluate athletes with sports-induced mild traumatic brain injury. We revised the original DTS for future clinical use and developed a neuroimaging-compatible version of the DTS to measure neural underpinnings of single and dual task performance.

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild ...

revised-and-neuroimaging-compatible-versions-of-the-dual-task-screen

Research

JoVE Journal

Behavior

3.5K Views.  Colorado State University. We ontwikkelden het originele Dual Task Screen (DTS) als een draagbare, goedkope maatregel die atleten met sportgeïnduceerd licht traumatisch hersenletsel kan evalueren. We hebben de originele DTS voor toekomstig klinisch gebruik herzien en een neuroimaging-compatibele versie van de DTS ontwikkeld om neurale onderbouwing van prestaties met één en dubbele taak te meten.

Video: Revised and Neuroimaging-Compatible Versions of the Dual Task Screen

Transferring Cognitive Tasks Between Brain Imaging Modalities: Implications for Task Design and Results Interpretation in fMRI Studies

As cognitive neuroscience methods develop, established experimental tasks are used with emerging brain imaging modalities. Here transferring a paradigm (the visual oddball task) with a long history of behavioral and electroencephalography (EEG) experiments to a functional magnetic resonance imaging (fMRI) experiment is considered. The aims of this paper are to briefly describe fMRI and when its use is appropriate in cognitive neuroscience; illustrate how task design can influence the results of an fMRI experiment, particularly when that task is borrowed from another imaging modality; explain the practical aspects of performing an fMRI experiment. It is demonstrated that manipulating the task demands in the visual oddball task results in different patterns of blood oxygen level dependent (BOLD) activation. The nature of the fMRI BOLD measure means that many brain regions are found to be active in a particular task. Determining the functions of these areas of activation is very much dependent on task design and analysis. The complex nature of many fMRI tasks means that the details of the task and its requirements need careful consideration when interpreting data. The data show that this is particularly important in those tasks relying on a motor response as well as cognitive elements and that covert and overt responses should be considered where possible. Furthermore, the data show that transferring an EEG paradigm to an fMRI experiment needs careful consideration and it cannot be assumed that the same paradigm will work equally well across imaging modalities. It is therefore recommended that the design of an fMRI study is pilot tested behaviorally to establish the effects of interest and then pilot tested in the fMRI environment to ensure appropriate design, implementation and analysis for the effects of interest.

Transferring a paradigm with a history of use in EEG experiments to an fMRI experiment is considered. It is demonstrated that manipulating the task demands in the visual oddball task resulted in different patterns of BOLD activation and illustrated how task design is crucial in fMRI experiments.

As cognitive neuroscience methods develop, established experimental tasks are used with emerging brain imaging modalities. Here transferring a paradigm ...

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 ...

Functional Near Infrared Spectroscopy of the Sensory and Motor Brain Regions with Simultaneous Kinematic and EMG Monitoring During Motor Tasks

There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is relatively flexible with respect to participant positioning and allows for some head movements during tasks. Additionally, it is inexpensive, light weight, and portable, with very few contraindications to its use. This presents a unique opportunity to study functional brain activity during motor tasks in individuals who are typically developing, as well as those with movement disorders, such as cerebral palsy. An additional consideration when studying movement disorders, however, is the quality of actual movements performed and the potential for additional, unintended movements. Therefore, concurrent monitoring of both blood flow changes in the brain and actual movements of the body during testing is required for appropriate interpretation of fNIRS results. Here, we show a protocol for the combination of fNIRS with muscle and kinematic monitoring during motor tasks. We explore gait, a unilateral multi-joint movement (cycling), and two unilateral single-joint movements (isolated ankle dorsiflexion, and isolated hand squeezing). The techniques presented can be useful in studying both typical and atypical motor control, and can be modified to investigate a broad range of tasks and scientific questions.

Monitoring brain activity during upright motor tasks is of great value when investigating the neural source of movement disorders. Here, we demonstrate a protocol that combines functional near infrared spectroscopy with continuous monitoring of muscle and kinematic activity during 4 types of motor tasks.

There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is ...

Utilizing Electroencephalography Measurements for Comparison of Task-Specific Neural Efficiencies: Spatial Intelligence Tasks

Spatial intelligence is often linked to success in engineering education and engineering professions. The use of electroencephalography enables comparative calculation of individuals&#39; neural efficiency as they perform successive tasks requiring spatial ability to derive solutions. Neural efficiency here is defined as having less beta activation, and therefore expending fewer neural resources, to perform a task in comparison to other groups or other tasks. For inter-task comparisons of tasks with similar durations, these measurements may enable a comparison of task type difficulty. For intra-participant and inter-participant comparisons, these measurements provide potential insight into the participant&#39;s level of spatial ability and different engineering problem solving tasks. Performance on the selected tasks can be analyzed and correlated with beta activities. This work presents a detailed research protocol studying the neural efficiency of students engaged in the solving of typical spatial ability and Statics problems. Students completed problems specific to the Mental Cutting Test (MCT), Purdue Spatial Visualization test of Rotations (PSVT:R), and Statics. While engaged in solving these problems, participants&#39; brain waves were measured with EEG allowing data to be collected regarding alpha and beta brain wave activation and use. The work looks to correlate functional performance on pure spatial tasks with spatially intensive engineering tasks to identify the pathways to successful performance in engineering and the resulting improvements in engineering education that may follow.

This manuscript describes an approach to measure neural activity of humans while solving spatially focused engineering problems. The electroencephalogram methodology helps interpret beta brain wave measurements in terms of neural efficiency, with the aim of ultimately enabling comparisons of task performance both between problem types and between participants.

Spatial intelligence is often linked to success in engineering education and engineering professions. The use of electroencephalography enables ...

Eye-Tracking Control to Assess Cognitive Functions in Patients with Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with pathological involvement of upper and lower motoneurons, subsequently leading to progressive loss of motor and speech abilities. In addition, cognitive functions are impaired in a subset of patients. To evaluate these potential deficits in severely physically impaired ALS patients, eye-tracking is a promising means to conduct cognitive tests. The present article focuses on how eye movements, an indirect means of communication for physically disabled patients, can be utilized to allow for detailed neuropsychological assessment. The requirements, in terms of oculomotor parameters that have to be met for sufficient eye-tracking in ALS patients are presented. The properties of stimuli, including type of neuropsychological tests and style of presentation, best suited to successfully assess cognitive functioning, are also described. Furthermore, recommendations regarding procedural requirements are provided. Overall, this methodology provides a reliable, easy to administer and fast approach for assessing cognitive deficits in patients who are unable to speak or write such as patients with severe ALS. The only confounding factor might be deficits in voluntary eye movement control in a subset of ALS patients.

Cognitive deficits are common in about one third of patients with amyotrophic lateral sclerosis, a neurological condition leading to progressive impairments in speech and movement abilities. To conduct cognitive tests in patients unable to speak or write a reliable and easy to administer eye-tracking paradigm was developed.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with pathological involvement of upper and lower motoneurons, subsequently leading to ...

Simultaneous Eye Tracking and Single-Neuron Recordings in Human Epilepsy Patients

Intracranial recordings from patients with intractable epilepsy provide a unique opportunity to study the activity of individual human neurons during active behavior. An important tool for quantifying behavior is eye tracking, which is an indispensable tool for studying visual attention. However, eye tracking is challenging to use concurrently with invasive electrophysiology and this approach has consequently been little used. Here, we present a proven experimental protocol to conduct single-neuron recordings with simultaneous eye tracking in humans. We describe how the systems are connected and the optimal settings to record neurons and eye movements. To illustrate the utility of this method, we summarize results that were made possible by this setup. This data shows how using eye tracking in a memory-guided visual search task allowed us to describe a new class of neurons called target neurons, whose response was reflective of top-down attention to the current search target. Lastly, we discuss the significance and solutions to potential problems of this setup. Together, our protocol and results suggest that single-neuron recordings with simultaneous eye tracking in humans are an effective method to study human brain function. It provides a key missing link between animal neurophysiology and human cognitive neuroscience.

We describe a method to conduct single-neuron recordings with simultaneous eye tracking in humans. We demonstrate the utility of this method and illustrate how we used this approach to obtain neurons in the human medial temporal lobe that encode targets of a visual search.

Intracranial recordings from patients with intractable epilepsy provide a unique opportunity to study the activity of individual human neurons during ...

Motor Dual-Tasks for Gait Analysis and Evaluation in Post-Stroke Patients

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask gait analysis consisted of a single walking task (Task 0), a simple motor dual-task (water-holding, Task 1), and a complex motor dual-task (crossing obstacles, Task 2). The task of crossing obstacles was considered to be equivalent to the combination of a simple walking task and a complex motor task as it involved more nervous system, skeletal movement, and cognitive resources. To eliminate heterogeneity in the results of the gait analysis of the stroke patients, the dual-task gait cost values were calculated for various kinematic parameters. The major differences were observed in the proximal joint angles, especially in the angles of the trunk, pelvis, and hip joints, which were significantly larger in the dual motor tasks than in the single walking task. This research protocol aims to provide a basis for the clinical diagnosis of gait function and an in-depth study of motor control in stroke patients with motor control deficits through the analyses of dual-motor walking tasks.

This paper presents a protocol specifically for dual motor task gait analysis in stroke patients with motor control deficits.

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask ...

Neuroscience

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Unilateral spatial neglect (USN) is a syndrome characterized by inattention to or inaction in one side of space and affects between 23-46% of acute stroke survivors. The diagnosis and characterization of these symptoms in individual patients can be challenging and often requires skilled clinical staff. Virtual reality (VR) presents an opportunity to develop novel assessment tools for patients with USN.
We aimed to design and build a VR tool to detect and characterize subtle USN symptoms, and to test the tool on subjects treated with inhibitory repetitive transcranial magnetic stimulation (TMS) of cortical regions associated with USN.
We created three experimental conditions by applying TMS to two distinct regions of cortex associated with visuospatial processing- the superior temporal gyrus (STG) and the supramarginal gyrus (SMG) - and applied sham TMS as a control. We then placed subjects in a virtual reality environment in which they were asked to identify the flowers with lateral asymmetries of flowers distributed across bushes in both hemispaces, with dynamic difficulty adjustment based on each subject's performance. 
We found significant differences in average head yaw between subjects stimulated at the STG and those stimulated at the SMG and marginally significant effects in the average visual axis.
VR technology is becoming more accessible, affordable, and robust, presenting an exciting opportunity to create useful and novel game-like tools. In conjunction with TMS, these tools could be used to study specific, isolated, artificial neurological deficits in healthy subjects, informing the creation of VR-based diagnostic tools for patients with deficits due to acquired brain injury. This study is the first to our knowledge in which artificially generated USN symptoms have been evaluated with a VR task.

The goal was to design, build, and pilot a novel virtual reality task to detect and characterize unilateral spatial neglect, a syndrome affecting 23-46% of acute stroke survivors, expanding the role of virtual reality in the study and management of neurologic disease.

Unilateral spatial neglect (USN) is a syndrome characterized by inattention to or inaction in one side of space and affects between 23-46% of acute stroke ...

Medicine

Dual-Task Stroop Paradigm for Detecting Cognitive Deficits in High-Functioning Stroke Patients

General clinical cognitive assessment scales are not sensitive enough to cognitive impairment in high-functioning stroke patients. The dual-task assessment has advantages for identifying cognitive deficits in high-functioning stroke patients and has been gradually applied in clinical assessment and cognitive training. Moreover, the Stroop paradigm has higher sensitivity and specificity for attentional assessment than conventional clinical cognitive assessment scales. Therefore, this study presents the dual-task assessment based on the Stroop paradigm to identify cognitive deficits in high-functioning stroke patients. This study demonstrates a single- and dual-task evaluation based on the Stroop paradigm and confirms its feasibility through case experiments and synchronized functional near-infrared spectroscopy evaluation. The Stroop reaction time and correct rate are used as the main indicators to evaluate the cognitive level of the subjects. This study protocol aims to provide new ideas to figure out the ceiling effect in general clinical assessment failure for high-functioning stroke patients.

Clinical assessment scales are notsensitive enough to cognitive dysfunction in high-functioning stroke patients. The dual-task paradigm presents advantages and potential in the assessment and cognitive training of cognitive dysfunction. The study here proposes a dual-task Stroop paradigm to identify cognitive dysfunction in high-functioning stroke patients.

General clinical cognitive assessment scales are not sensitive enough to cognitive impairment in high-functioning stroke patients. The dual-task ...

Scalp Acupuncture Synchronizing Dual Task Gait for Enhancing Prefrontal Cortex Response

Studies have shown that motor-cognitive dual task can greatly improve motor/cognitive function. However, the therapeutic effect of motor-cognitive dual task is still limited. How to improve dual-task performance is the key to solving this problem. Scalp acupuncture is a non-drug intervention method of traditional Chinese medicine to treat brain-derived diseases by acupuncturing the corresponding projection area of cerebral cortex function on the scalp. Studies have shown that scalp acupuncture helps improve neuronal damage and cognitive dysfunction and plays a neuroprotective function in central nervous system diseases. However, no relevant studies have discussed the synergistic gain effect of motor-cognitive dual task and scalp acupuncture. Therefore, this protocol aims to demonstrate the standardized operation of scalp acupuncture synchronizing motor-cognitive dual task and motor-cognitive dual task and compares the differences between these two tasks in healthy subjects through a randomized cross-over trial. This protocol initially revealed the possible influence mechanism of scalp acupuncture synchronizing motor-cognitive dual task on cognitive performance, gait control, and cortical brain function, which can provide new ideas and a theoretical basis for clinical exploration of new and effective non-drug treatment of integrated Chinese and Western medicine.

This protocol demonstrates the standardized procedure of scalp acupuncture synchronizing motor-cognitive dual task and motor-cognitive dual task. This can provide an important reference for the clinical exploration of the new and effective non-drug treatment of integrated Chinese and Western medicine.

Studies have shown that motor-cognitive dual task can greatly improve motor/cognitive function. However, the therapeutic effect of motor-cognitive dual ...

Revised and Neuroimaging-Compatible Versions of the Dual Task Screen

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