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>

<ol>
	<li>Gardner, R. C., Yaffe, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiology+of+mild+traumatic+brain+injury+and+neurodegenerative+disease.">Epidemiology of mild traumatic brain injury and neurodegenerative disease.</a> Molecular and Cellular Neuroscience. 66, 75-80 (2015).</li><li>Oyegbile, T. O., Dougherty, A., Tanveer, S., Zecavati, N., Delasobera, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+Sleep+Disturbance+and+Longer+Concussion+Duration+in+Repeat+Concussions.">High Sleep Disturbance and Longer Concussion Duration in Repeat Concussions.</a> Behavioral Sleep Medicine. , 1-8 (2019).</li><li>Schatz, P., Moser, R. S., Covassin, T., Karpf, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+indicators+of+enduring+symptoms+in+high+school+athletes+with+multiple+previous+concussions.">Early indicators of enduring symptoms in high school athletes with multiple previous concussions.</a> Neurosurgery. 68 (6), 1562-1567 (2011).</li><li>Yrondi, A., Brauge, D., LeMen, J., Arbus, C., Pariente, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Depression+and+sports-related+concussion:+A+systematic+review.">Depression and sports-related concussion: A systematic review.</a> La Presse M&#233;dicale. 46 (10), 890-902 (2017).</li><li>Haider, M. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+systematic+review+of+criteria+used+to+define+recovery+from+sport-related+concussion+in+youth+athletes.">A systematic review of criteria used to define recovery from sport-related concussion in youth athletes.</a> British Journal of Sports Medicine. 52 (18), 1179-1190 (2018).</li><li>Conway, F. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Concussion+Symptom+Underreporting+Among+Incoming+National+Collegiate+Athletic+Association+Division+I+College+Athletes.">Concussion Symptom Underreporting Among Incoming National Collegiate Athletic Association Division I College Athletes.</a> Clinical Journal of Sport Medicine. 30 (3), 203-209 (2020).</li><li>Broglio, S. P., Guskiewicz, K. M., Norwig, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=If+You're+Not+Measuring,+You're+Guessing:+The+Advent+of+Objective+Concussion+Assessments.">If You're Not Measuring, You're Guessing: The Advent of Objective Concussion Assessments.</a> Journal of Athletic Training. 52 (3), 160-166 (2017).</li><li>Broglio, S. P., Katz, B. P., Zhao, S., McCrea, M., McAllister, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Test-retest+reliability+and+interpretation+of+common+concussion+assessment+tools:+Findings+from+the+NCAA-DoD+CARE+Consortium.">Test-retest reliability and interpretation of common concussion assessment tools: Findings from the NCAA-DoD CARE Consortium.</a> Sports Medicine. 48 (5), 1255-1268 (2018).</li><li>Howell, D. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Examining+Motor+Tasks+of+Differing+Complexity+After+Concussion+in+Adolescents.">Examining Motor Tasks of Differing Complexity After Concussion in Adolescents.</a> Archives of Physical Medicine and Rehabilitation. 100 (4), 613-619 (2019).</li><li>Buttner, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Concussed+athletes+walk+slower+than+non-concussed+athletes+during+cognitive-motor+dual-task+assessments+but+not+during+single-task+assessments+2+months+after+sports+concussion:+a+systematic+review+and+meta-analysis+using+individual+participant+data.">Concussed athletes walk slower than non-concussed athletes during cognitive-motor dual-task assessments but not during single-task assessments 2 months after sports concussion: a systematic review and meta-analysis using individual participant data.</a> British Journal of Sports Medicine. 54 (2), 94-101 (2020).</li><li>Howell, D. R., Buckley, T. A., Lynall, R. C., Meehan, W. P. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Worsening+dual-task+gait+costs+after+concussion+and+their+association+with+subsequent+sport-related+injury.">Worsening dual-task gait costs after concussion and their association with subsequent sport-related injury.</a> Journal of Neurotrauma. 35 (14), 1630-1636 (2018).</li><li>Howell, D. R., Kirkwood, M. W., Provance, A., Iverson, G. L., Meehan, W. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+concurrent+gait+and+cognitive+assessments+to+identify+impairments+after+concussion:+a+narrative+review.">Using concurrent gait and cognitive assessments to identify impairments after concussion: a narrative review.</a> Concussion. 3 (1), 54 (2018).</li><li>Lee, H., Sullivan, S. J., Schneiders, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+the+dual-task+paradigm+in+detecting+gait+performance+deficits+following+a+sports-related+concussion:+a+systematic+review+and+meta-analysis.">The use of the dual-task paradigm in detecting gait performance deficits following a sports-related concussion: a systematic review and meta-analysis.</a> Journal of Science and Medicine in Sport. 16 (1), 2-7 (2013).</li><li>Solomito, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motion+analysis+evaluation+of+adolescent+athletes+during+dual-task+walking+following+a+concussion:+A+multicenter+study.">Motion analysis evaluation of adolescent athletes during dual-task walking following a concussion: A multicenter study.</a> Gait Posture. 64, 260-265 (2018).</li><li>Stephens, J. A., Nicholson, R., Slomine, B., Suskauer, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+pilot+testing+of+the+dual+task+screen+in+healthy+adolescents.">Development and pilot testing of the dual task screen in healthy adolescents.</a> American Journal of Occupational Therapy. 72 (3), (2018).</li><li>Ptak, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+frontoparietal+attention+network+of+the+human+brain:+action,+saliency,+and+a+priority+map+of+the+environment.">The frontoparietal attention network of the human brain: action, saliency, and a priority map of the environment.</a> Neuroscientist. 18 (5), 502-515 (2012).</li><li>Jasper, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Report+of+the+committee+on+methods+of+clinical+examination+in+electroencephalography:+1957.">Report of the committee on methods of clinical examination in electroencephalography: 1957.</a> Electroencephalography and Clinical Neurophysiology. 10 (2), 370-375 (1958).</li><li>Brigadoi, S., Cooper, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+short+is+short?+Optimum+source-detector+distance+for+short-separation+channels+in+functional+near-infrared+spectroscopy.">How short is short? Optimum source-detector distance for short-separation channels in functional near-infrared spectroscopy.</a> Neurophotonics. 2 (2), 025005 (2015).</li><li>Sato, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduction+of+global+interference+of+scalp-hemodynamics+in+functional+near-infrared+spectroscopy+using+short+distance+probes.">Reduction of global interference of scalp-hemodynamics in functional near-infrared spectroscopy using short distance probes.</a> Neuroimage. 141, 120-132 (2016).</li><li>Scholkmann, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+on+continuous+wave+functional+near-infrared+spectroscopy+and+imaging+instrumentation+and+methodology.">A review on continuous wave functional near-infrared spectroscopy and imaging instrumentation and methodology.</a> Neuroimage. 85, 6-27 (2014).</li><li>Baker, W. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modified+Beer-Lambert+law+for+blood+flow.">Modified Beer-Lambert law for blood flow.</a> Biomedical Optics Express. 5 (11), 4053-4075 (2014).</li><li>Barker, J. W., Aarabi, A., Huppert, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autoregressive+model+based+algorithm+for+correcting+motion+and+serially+correlated+errors+in+fNIRS.">Autoregressive model based algorithm for correcting motion and serially correlated errors in fNIRS.</a> Biomedical Optics Express. 4 (8), 1366-1379 (2013).</li><li>Aguirre, G. K., Zarahn, E., D'Esposito, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+variability+of+human,+BOLD+hemodynamic+responses.">The variability of human, BOLD hemodynamic responses.</a> Neuroimage. 8 (4), 360-369 (1998).</li><li>Stephens, J. A., Liu, P., Lu, H., Suskauer, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebral+Blood+Flow+after+Mild+Traumatic+Brain+Injury:+Associations+between+Symptoms+and+Post-Injury+Perfusion.">Cerebral Blood Flow after Mild Traumatic Brain Injury: Associations between Symptoms and Post-Injury Perfusion.</a> Journal of Neurotrauma. 35 (2), 241-248 (2018).</li></ol>

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>Hardware (in alphabetical order)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>NIRx NIRSport2 Device: NSP2-CORE1616</td>
			<td>NIRx</td>
			<td>Reference #: GC359</td>
			<td>&#34;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.&#34; (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>&#34;The NIRScap consists of a measuring cap and optode holders. The optode holders fit into the slits of the measuring cap.&#34; (Direct quote from NIRx&#39;s NIRScap Getting Started Guide)</td>
		</tr>
		<tr>
			<td>NIRx Optode Sources (x 2)</td>
			<td>NIRx</td>
			<td>Reference #: GC359</td>
			<td>&#34;8-source active source bundel for fiberless optical illumination with dual tip; 240 cm long.&#34; (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>&#34;Bundle of 8x active sensores for fiberless optical detection; dual tip; 240 cm long.&#34; (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>&#34;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.&#34; (Direct quote from NIRx&#39;s Short Distance Detector Probes Getting Started Guide)</td>
		</tr>
		<tr>
			<td>Software (in alphabetical order)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Aurora</td>
			<td>NIRx</td>
			<td>N/A</td>
			<td>&#34;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.&#34; (Direct quote from nirx.net/software)</td>
		</tr>
		<tr>
			<td>Matlab</td>
			<td>Math Works</td>
			<td>N/A</td>
			<td>&#34;MATLAB&#174; 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.&#34; (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>&#34;NIRS toolbox is a Matlab based analysis program.&#34; (Direct quote from huppertlab.net/nirs-toolbox-2/)</td>
		</tr>
		<tr>
			<td>PsychoPy</td>
			<td>Python</td>
			<td>N/A</td>
			<td>&#34;PsychoPy is an open source software package written in the Python program,ming language primarily for us in neuroscience and experimntal psychology research.&#34; (Direct quote from psychopy.org)</td>
		</tr>
		<tr>
			<td>Lower Tech/Cost Research Supplies* (in alphabetical order)</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&#8217;s legs can extend from 20&#8221; to 48&#8221;. Leg locks release smoothly and glide easily to your desired height. Crank up the center post for a tripod that is 60&#8221; 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&#8217;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&#8217;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.&#34; (Direct quote from Amazon.com)</td>
		</tr>
		<tr>
			<td>Post-it Notes, 3&#34; x 3&#34;, Canary Yellow, Pack Of 18 Pads</td>
			<td>Office Depot/Office Max</td>
			<td>Item # 1230652</td>
			<td>&#34;Post it&#174; Notes stick securely and remove cleanly, featuring a unique adhesive designed for use on paper.&#34;</td>
		</tr>
		<tr>
			<td>Scotch 232 Masking Tape, 1&#34; x 60 Yd</td>
			<td>Office Depot/Office Max</td>
			<td>Item # 910588</td>
			<td>&#34;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.&#34; (Direct quote from officedepot.com)</td>
		</tr>
		<tr>
			<td>Stanley Tools Leverlock Tape Measure, Standard, 25&#39; x 1&#34; Blade</td>
			<td>Office Depot/Office Max</td>
			<td>Item #389512</td>
			<td>&#34;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.&#34; (Direct quote from officedepot.com)</td>
		</tr>
		<tr>
			<td>Stopwatch</td>
			<td>Office Depot/Office Max</td>
			<td>Item # 357698</td>
			<td>&#34;Offers split timing, precise to 1/100 of a second. Includes 6 functions &#8212; hour, minute, second, day, month and year.&#34; (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>&#34;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&#39;t fall out during transport. Bars roll at the bottom so the ball slips in the hopper easily.&#34; (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>&#34;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.&#34; (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 &#8211; 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>&#34;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.&#34; (Direct quote from Amazon.com)</td>
		</tr>
		<tr>
			<td>*These items or comparable items can be obtained from a number of other sources</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...

Watch this Scientific Journal Video about Revised and Neuroimaging-Compatible Versions of the Dual Task Screen at JoVE.com

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

3.4K Views.  Colorado State University. 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.

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

The 5-Choice Serial Reaction Time Task: A Task of Attention and Impulse Control for Rodents

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. Test day challenges, modifications to the standard task, can be used to systematically tax the neural systems controlling either attention or impulse control. Importantly, these challenges have consistent effects on behavior across laboratories in intact animals and can reveal either enhancements or deficits in cognitive function that are not apparent when rats are only tested on the standard task. The variety of behavioral measures that are collected can be used to determine if other factors (i.e., sedation, motivation deficits, locomotor impairments) are contributing to changes in performance. The versatility of the 5CSRTT is further enhanced because it is amenable to combination with pharmacological, molecular, and genetic techniques.

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. Test day challenges, which are modifications of the standard task, increase flexibility of the task and can be combined with other manipulations to more fully characterize behavior.

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. ...

Using the Threat Probability Task to Assess Anxiety and Fear During Uncertain and Certain Threat

Fear of certain threat and anxiety about uncertain threat are distinct emotions with unique behavioral, cognitive-attentional, and neuroanatomical components. Both anxiety and fear can be studied in the laboratory by measuring the potentiation of the startle reflex. The startle reflex is a defensive reflex that is potentiated when an organism is threatened and the need for defense is high. The startle reflex is assessed via electromyography (EMG) in the orbicularis oculi muscle elicited by brief, intense, bursts of acoustic white noise (i.e., &#8220;startle probes&#8221;). Startle potentiation is calculated as the increase in startle response magnitude during presentation of sets of visual threat cues that signal delivery of mild electric shock relative to sets of matched cues that signal the absence of shock (no-threat cues). In the Threat Probability Task, fear is measured via startle potentiation to high probability (100% cue-contingent shock; certain) threat cues whereas anxiety is measured via startle potentiation to low probability (20% cue-contingent shock; uncertain) threat cues. Measurement of startle potentiation during the Threat Probability Task provides an objective and easily implemented alternative to assessment of negative affect via self-report or other methods (e.g., neuroimaging) that may be inappropriate or impractical for some researchers. Startle potentiation has been studied rigorously in both animals (e.g., rodents, non-human primates) and humans which facilitates animal-to-human translational research. Startle potentiation during certain and uncertain threat provides an objective measure of negative affective and distinct emotional states (fear, anxiety) to use in research on psychopathology, substance use/abuse and broadly in affective science. As such, it has been used extensively by clinical scientists interested in psychopathology etiology and by affective scientists interested in individual differences in emotion.

Potentiation of the startle reflex is measured via electromyography of the orbicularis oculi muscle during low (uncertain) and high (certain) probability electric shock threat in the Threat Probability Task. This provides an objective measure of distinct negative emotional states (fear/anxiety) for research on psychopathology, substance use/abuse, and broad affective science.

Fear of certain threat and anxiety about uncertain threat are distinct emotions with unique behavioral, cognitive-attentional, and neuroanatomical ...

fMRI Validation of fNIRS Measurements During a Naturalistic Task

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced version of the task using fMRI (functional magnetic resonance imaging). Recently, it has been shown that fNIRS can accurately record functional brain activities equivalent to those concurrently recorded with functional magnetic resonance imaging for classic psychophysical tasks and simple finger tapping paradigms. However, an often quoted benefit of fNIRS is that the technique allows for studying neural mechanisms of complex, naturalistic behaviors that are not possible using the constrained environment of fMRI. Our goal was to extend the findings of previous studies that have shown high correlation between concurrently recorded fNIRS and fMRI signals to compare neural recordings obtained in fMRI procedures to those separately obtained in naturalistic fNIRS experiments. Specifically, we developed a modified version of the dance video game Dance Dance Revolution (DDR) to be compatible with both fMRI and fNIRS imaging procedures. In this methodology we explain the modifications to the software and hardware for compatibility with each technique as well as the scanning and calibration procedures used to obtain representative results. The results of the study show a task-related increase in oxyhemoglobin in both modalities and demonstrate that it is possible to replicate the findings of fMRI using fNIRS in a naturalistic task. This technique represents a methodology to compare fMRI imaging paradigms which utilize a reduced-world environment to fNIRS in closer approximation to naturalistic, full-body activities and behaviors. Further development of this technique may apply to neurodegenerative diseases, such as Parkinson&#8217;s disease, late states of dementia, or those with magnetic susceptibility which are contraindicated for fMRI scanning.

We present a method to compare functional brain activity recorded during a naturalistic task using fNIRS with activity recorded during fMRI.

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced ...

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 ...

Quantifying Learning in Young Infants: Tracking Leg Actions During a Discovery-learning Task

Task-specific actions emerge from spontaneous movement during infancy. It has been proposed that task-specific actions emerge through a discovery-learning process. Here a method is described in which 3-4 month old infants learn a task by discovery and their leg movements are captured to quantify the learning process. This discovery-learning task uses an infant activated mobile that rotates and plays music based on specified leg action of infants. Supine infants activate the mobile by moving their feet vertically across a virtual threshold. This paradigm is unique in that as infants independently discover that their leg actions activate the mobile, the infants&#8217; leg movements are tracked using a motion capture system allowing for the quantification of the learning process. Specifically, learning is quantified in terms of the duration of mobile activation, the position variance of the end effectors (feet) that activate the mobile, changes in hip-knee coordination patterns, and changes in hip and knee muscle torque. This information describes infant exploration and exploitation at the interplay of person and environmental constraints that support task-specific action. Subsequent research using this method can investigate how specific impairments of different populations of infants at risk for movement disorders influence the discovery-learning process for task-specific action.

A method is described in which 3-4 month old infants learn a task by discovery and their leg movements are captured to quantify the learning process.

Task-specific actions emerge from spontaneous movement during infancy. It has been proposed that task-specific actions emerge through a discovery-learning ...

The Emotional Stroop Task: Assessing Cognitive Performance under Exposure to Emotional Content

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than to ink colors of neutral words. The difference shows that people are affected by the emotional content conveyed by the carrier words even though they are irrelevant to the color-naming task at hand. The ESE has been widely deployed with patient populations, as well as with non-selected populations, because the emotion words can be selected to match the tested pathology. The ESE is a powerful tool, yet it is vulnerable to various threats to its validity. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them. The most prevalent threat to the validity of existing ESE studies is sustained effects and habituation wrought about by repeated exposure to emotion stimuli. Consequently, the order of exposure to emotion and neutral stimuli is of utmost importance. We show that in the standard design, only one specific order produces the ESE.

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than those of neutral words. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them.

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than to ink colors of neutral words. The ...

Task Interruption and Resumption Paradigm for Testing the Activation and Pursuit of an Abstract Thinking Goal

This protocol is based on the task interruption and resumption paradigm, the premise of which is that active goals lead to persistent behavior and thus a higher resumption rate after a period of delay or interruption. The task interruption and resumption protocol described in this research is tailored to test the activation of cognitive goals (e.g., a goal to think more abstractly). Cognitive goals may be pursued even during the interruption period; thus, to prevent this, the protocol involves cognitive distraction. The protocol consists of several stages. Specifically, the initial stage includes the goal activation process, where the treatment (versus control) condition receives a manipulation to activate the cognitive goal being tested by the researcher. In the next stage, participants are presented with the introduction of a task that is perceived to either satisfy or not satisfy the cognitive goal of interest. Importantly, this task is interrupted a few seconds after it begins. The task interruption forces a delay period and introduces a cognitive distraction to prevent the automatic pursuit and fulfillment of the cognitive goal. After the interruption period, participants are given a choice between resuming the interrupted task and abandoning the interrupted task to complete an alternative task instead. Among participants whose cognitive goals had been activated at the earlier stage, the task resumption rate should be higher if the task was perceived as an opportunity to satisfy (versus not satisfy) the goal. Such a finding would provide empirical evidence that the cognitive goal has been activated and pursued. In previous research, this protocol has been used to test whether causal uncertainty activates an abstract thinking goal. Adapting the protocol to test the activation of other cognitive goals is also discussed.

This protocol was designed to test the activation and pursuit of cognitive goals (e.g., an abstract thinking goal) using the task interruption and resumption paradigm. The protocol is suitable for cognitive goals that are automatically pursued once activated, as the distraction procedure prevents goal pursuit during the interruption period.

This protocol is based on the task interruption and resumption paradigm, the premise of which is that active goals lead to persistent behavior and thus a ...

The Knob Supination Task: A Semi-automated Method for Assessing Forelimb Function in Rats

Tasks that accurately measure dexterity in animal models are critical to understand hand function. Current rat behavioral tasks that measure dexterity largely use video analysis of reaching or food manipulation. While these tasks are easy to implement and are robust across disease models, they are subjective and laborious for the experimenter. Automating traditional tasks or creating new automated tasks can make the tasks more efficient, objective, and quantitative. Since rats are less dexterous than primates, central nervous system (CNS) injury produces more subtle deficits in dexterity, however, supination is highly affected in rodents and crucial to hand function in primates. Therefore, we designed a semi-automated task that measures forelimb supination in rats. Rats are trained to reach and grasp a knob-shaped manipulandum and turn the manipulandum in supination to receive a reward. Rats can acquire the skill within 20 &plusmn; 5 days. While the early part of training is highly supervised, much of the training is done without direct supervision. The task reliably and reproducibly captures subtle deficits after injury and shows functional recovery that accurately reflects clinical recovery curves. Analysis of data is performed by specialized software through a graphical user interface that is designed to be intuitive. We also give solutions to common problems encountered during training, and show that minor corrections to behavior early in training produce reliable acquisition of supination. Thus, the knob supination task provides efficient and quantitative evaluation of a critical movement for dexterity in rats.

This manuscript describes a semi-automated task that quantifies supination in rats. Rats reach, grasp, and supinate a spherical manipulandum. The rat is rewarded with a pellet if the turn angle exceeds a criterion set by the user. This task increases throughput, sensitivity to injury, and objectivity compared to traditional tasks.

Tasks that accurately measure dexterity in animal models are critical to understand hand function. Current rat behavioral tasks that measure dexterity ...

The "Motor" in Implicit Motor Sequence Learning: A Foot-stepping Serial Reaction Time Task

This protocol describes a modified serial reaction time (SRT) task used to study implicit motor sequence learning. Unlike the classic SRT task that involves finger-pressing movements while sitting, the modified SRT task requires participants to step with both feet while maintaining a standing posture. This stepping task necessitates whole body actions that impose postural challenges. The foot-stepping task complements the classic SRT task in several ways. The foot-stepping SRT task is a better proxy for the daily activities that require ongoing postural control, and thus may help us better understand sequence learning in real-life situations. In addition, response time serves as an indicator of sequence learning in the classic SRT task, but it is unclear whether response time, reaction time (RT) representing mental process, or movement time (MT) reflecting the movement itself, is a key player in motor sequence learning. The foot-stepping SRT task allows researchers to disentangle response time into RT and MT, which may clarify how motor planning and movement execution are involved in sequence learning. Lastly, postural control and cognition are interactively related, but little is known about how postural control interacts with learning motor sequences. With a motion capture system, the movement of the whole body (e.g., the center of mass (COM)) can be recorded. Such measures allow us to reveal the dynamic processes underlying discrete responses measured by RT and MT, and may aid in elucidating the relationship between postural control and the explicit and implicit processes involved in sequence learning. Details of the experimental set-up, procedure, and data processing are described. The representative data are adopted from one of our previous studies. Results are related to response time, RT, and MT, as well as the relationship between the anticipatory postural response and the explicit processes involved in implicit motor sequence learning.

We introduce the foot-stepping serial reaction time (SRT) task. This modified SRT task, complementing the classic SRT task that involves only finger-pressing movement, better approximates daily sequenced activities and allows researchers to study the dynamic processes underlying discrete response measures and disentangle the explicit process operating in implicit sequence learning.

This protocol describes a modified serial reaction time (SRT) task used to study implicit motor sequence learning. Unlike the classic SRT task that ...

The Modified Temptation Resistance Task: A Paradigm to Elicit Children's Strategic Lie-telling

The protocol for the temptation resistance paradigm was designed to elicit 2- to 8-year-old children's strategic lie-telling behaviors. The reward of transgression was intended to be too tempting to resist, so that children's spontaneous lie-telling behavior in the presence of irreversible evidence due to the transgression could be observed. Conducted in a developmental psychology laboratory behind a one-way mirror and video recorded with a hidden camcorder, the protocol starts with a guessing game where the child is given three trials to guess the identities of hidden objects under an upside down cup. The experimenter gives hints in the first two trials to make sure the child "guess" them correctly. At the beginning of the final trial, the experimenter leaves the room briefly and asks the child not to peek under the cup. If the child could not resist the temptation and peeks, small particles previously filled in the cup would scatter on a grooved surface. Upon the experimenter's return, the child is asked if he/she has peeked. If he/she denies transgression contrary to the presence of the physical evidence, he/she is asked to explain why the particles are on the table. Three responses could be observed in the procedure, including the initial transgression, truth-telling or lie-telling behavior if the child peeked, and the strategic lie-telling behavior in the presence of the physical evidence.

The protocol for the temptation resistance paradigm was designed to elicit 2- to 8-year-old children&#39;s strategic lie-telling behaviors. The reward of transgression was intended to be too tempting to resist, so that children&#39;s spontaneous lie-telling behavior in the presence of irreversible evidence due to the transgression could be observed.

The protocol for the temptation resistance paradigm was designed to elicit 2- to 8-year-old children's strategic lie-telling behaviors. The reward of ...