Dynamic Reaction Time: Jumping into the Future of Concussion Management

Abstract Purpose To explore the relationship between reaction time (RT) on a commonly used post-concussion computerized neurocognitive assessment and dynamic RT during sport-like movements, with and without a cognitive task. Methods Fourteen healthy individuals (7 females; age=22.3±2.5yrs, height=169.1±14.0cm, mass=71.1±16.8kg) completed a computerized Stroop task (CNS Vital Signs), where the individual presses the space bar when the color of the word does not match the word, and two dynamic RT tasks (jump landing [4 trials], anticipated cutting [8 trials]). Dynamic RT tasks were performed with (dual-task) and without (single-task) a cognitive task (subtracting by 6’s or 7’s). Participants jumped off of a 30cm box and then either performed a maximum vertical jump landing or an anticipated cut at 45. Dynamic RT, recorded using high-speed 3D-motion capture (Qualisys), was the average time (seconds) between visual stimulus and when participants’ sacrum moved >3cm in the sagittal or transverse plane. Pearson correlation coefficients (α=0.05) were calculated between all RT measures. Results Stroop RT (0.67±0.01s) was not significantly correlated with jump landing single-task (p=0.45; r=0.22), jump landing dual-task (p=0.10; r=0.45), anticipated cutting single-task (p=0.7; r=0.11), or anticipated cutting dual-task (p=0.85; r=0.06) RTs. We found positive correlations between all single- and dual-task dynamic RTs (p=.03, r=.56). Conclusion Stroop RT was not correlated with dynamic RTs, which may more closely reflect RT associated with sport participation. Commonly used computerized RT assessments may not fully represent the dynamic RT athletes need in sport tasks. Further investigation is warranted in order to develop the most appropriate RT assessments for post-concussion return-to-play.

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Detection of Persisting Concussion Effects on Measures of Neuromechanical Responsiveness

Neurosurgery ◽

10.1093/neuros/nyz310_834 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Chad J Prusmack

Keyword(s):

Reaction Time ◽

Dual Task ◽

Predictive Value ◽

Sport Participation ◽

Elite Athletes ◽

Recursive Partitioning ◽

Critical Role ◽

Return To Sport ◽

Return To Play ◽

Whole Body

Abstract INTRODUCTION Numerous investigations have documented elevated risk for musculoskeletal injury following sport-related concussion, which suggests that an unrecognized vulnerability persists beyond the resolution of symptoms and return to sport participation. Improved clinical testing methods are needed to better assess the interrelated neurocognitive and neuromuscular capabilities of athletes who may have elevated susceptibility to MSK injury, and possible risk for long- term alterations in brain function, despite resolution of overt concussion symptoms. The term “neuromechanics” refers to the study of interactions between neural, biomechanical, and environmental dynamics We use the term “neuromechanical responsiveness” (NMR) to designate the ability to optimally integrate neurocognitive and neuromuscular processes during participation in sport-related activities. NMR testing may play an critical role in optimizing safe return to play circumstances. METHODS A cohort of 48 elite athletes (34 males: 23.8 ± 4.4 yr; 14 females: 25.4 ± 4.5 yr) performed visuomotor reaction time (VMRT) tests involving rapid manual contact with illuminated target buttons that included 2 dual-task conditions: 1) simultaneous oral recitation of scrolling text (VMRT + ST) and 2) simultaneous verbal responses to identify the right or left direction indicated by the center arrow of the Eriksen flanker test (VMRT + FT). A whole-body reactive agility (WBRA) test requiring side-shuffle movements in response to visual targets was used to assess reaction time, speed, acceleration, and deceleration. RESULTS Concussion occurrence at 2.0 ± 2.3 yr prior to testing was reported by 21 athletes. Strong univariable associations were found for VMRT + FT left minus right difference = 15 ms (OR = 7.14), VMRT + ST outer 2-ring to inner 3-ring ratio = 1.28 (OR = 4.58), and WBRA speed asymmetry = 7.7% (OR = 4.67). A large VMRT + FT X VMRT + ST interaction effect was identified (OR = 25.00). Recursive partitioning identified a 3-way VMRT + FT X VMRT + ST X WBRA interaction that had 100% positive predictive value for identification of athletes with concussion history, whereas negative status on all 3 factors provided 90% negative predictive value. CONCLUSION Performance on dual-task VMRT tests and the WBRA test identified NMR deficiencies among elite athletes who reported a history of concussion.

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The effects of a concurrent task on walking in persons with transfemoral amputation compared to persons without limb loss

Prosthetics and Orthotics International ◽

10.1177/0309364615596066 ◽

2015 ◽

Vol 40 (4) ◽

pp. 490-496 ◽

Cited By ~ 20

Author(s):

Sara J Morgan ◽

Brian J Hafner ◽

Valerie E Kelly

Keyword(s):

Dual Task ◽

Repeated Measures ◽

Cognitive Task ◽

Cross Sectional Study ◽

Concurrent Task ◽

Limb Loss ◽

Transfemoral Amputation ◽

Cross Sectional ◽

Time Asymmetry ◽

Single Task

Background:Many people with lower limb loss report the need to concentrate on walking. This may indicate increased reliance on cognitive resources when walking compared to individuals without limb loss.Objective:This study quantified changes in walking associated with addition of a concurrent cognitive task in persons with transfemoral amputation using microprocessor knees compared to age- and sex-matched controls.Study design:Observational, cross-sectional study.Methods:Quantitative motion analysis was used to assess walking under both single-task (walking alone) and dual-task (walking while performing a cognitive task) conditions. Primary outcomes were walking speed, step width, step time asymmetry, and cognitive task response latency and accuracy. Repeated-measures analysis of variance was used to examine the effects of task (single-task and dual-task) and group (transfemoral amputation and control) for each outcome.Results:No significant interactions between task and group were observed (all p > 0.11) indicating that a cognitive task did not differentially affect walking between groups. However, walking was slower with wider steps and more asymmetry in people with transfemoral amputation compared to controls under both conditions.Conclusion:Although there were significant differences in walking between people with transfemoral amputation and matched controls, the effects of a concurrent cognitive task on walking were similar between groups.Clinical relevanceThe addition of a concurrent task did not differentially affect walking outcomes in people with and without transfemoral amputation. However, compared to people without limb loss, people with transfemoral amputation adopted a conservative walking strategy. This strategy may reduce the need to concentrate on walking but also contributed to notable gait deviations.

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Influence of Gymnastic Background on Triangle Completion Performance in Single and Dual-Task Conditions

The Open Sports Sciences Journal ◽

10.2174/1875399x01306010015 ◽

2013 ◽

Vol 6 (1) ◽

pp. 15-21 ◽

Cited By ~ 1

Author(s):

Andrei Garcia Popov ◽

Nicole Paquet ◽

Yves Lajoie

Keyword(s):

Reaction Time ◽

Dual Task ◽

Cognitive Task ◽

Linear Displacement ◽

Angular Deviation ◽

Linear Distance ◽

Task Conditions ◽

And Control ◽

Triangle Completion ◽

The Impact

Spatial orientation skills of gymnasts have been investigated in the past, but their navigation skills have not been well described. For instance, little is known on their performance on triangle completion in the absence of vision. The question is whether gymnasts require less attention than non-gymnasts in executing this task. The aims were to study the impact of dual-task on triangle completion performance and reaction time, and to compare this effect in young adults with or without a gymnastic background. Participants were blindfolded and guided along the first two legs of a 5x5 m right angle triangle and then, independently turned and walked towards the origin of this triangle. After they had stopped, their foot position was marked on the floor and angular deviation and linear distance traveled were measured. In the dualtask, reaction time was gathered during the independent walk with participants responding verbally ‘top’ as fast as possible after a sound signal. Gymnasts were found to have smaller angular deviation and longer linear distance traveled than non-gymnasts. Both groups showed longer reaction time in dual-task compared to baseline in sitting and this increase was similar for both groups. The results suggest that gymnastics training improves the perception and control of direction. However, it does not modify perception of linear displacement, nor the attention required to execute the triangle completion task. In dual-task, other cognitive tasks requiring working memory might have had a larger impact on both navigation errors and cognitive task performance.

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Dual-Task Measures of S-R Compatibility

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/1071181379023001106 ◽

1979 ◽

Vol 23 (1) ◽

pp. 422-426

Author(s):

George D. Ogden ◽

Nancy S. Anderson ◽

Angela M. Rieck

Keyword(s):

Reaction Time ◽

Task Performance ◽

Dual Task ◽

Tracking Task ◽

Single Task ◽

Induced Stress ◽

Task Setting ◽

Choice Reaction Task ◽

Reaction Performance ◽

Reaction Task

The present study was designed to compare single-task and dual-task measures of S-R compatibility. A numeral-motor choice-reaction task was performed alone and with a secondary tracking task. The level of compatibility was varied by manipulating the S-R assignments in the choice-reaction task. Results of the single-task trials indicated that reaction time was significantly slower for the incompatible conditions. Reaction time was slower, more errors were made, and fewer problems were attempted in the incompatible dual-task trials. Despite instructions to maintain choice-reaction performance at single-task levels, incompatible task performance was significantly degraded in the dual-task setting. Results indicated that resistance to task-induced stress may be a major indicant of the level of compatibility.

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DUAL-TASK BALANCE CONTROL IN ADOLESCENT ATHLETES FOLLOWING CONCUSSION

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120s00152 ◽

2020 ◽

Vol 8 (4_suppl3) ◽

pp. 2325967120S0015

Author(s):

Tracy Zaslow ◽

Camille Burton ◽

Nicole M. Mueske ◽

Adriana Conrad-Forrest ◽

Bianca Edison ◽

...

Keyword(s):

Dual Task ◽

Verbal Fluency ◽

Walking Speed ◽

Balance Control ◽

Dynamic Balance ◽

Center Of Mass ◽

Quiet Standing ◽

Return To Play ◽

Treatment Protocols ◽

Single Task

Background: Previous research has identified deficient dual-task balance control at the time of return to play (RTP) and possible worsening after RTP in older adolescents/young adults with concussion. These findings have not been investigated in younger patients with concussion. Hypothesis/Purpose: We hypothesized that concussed adolescents would have slower walking speed and increased medial-lateral (ML) center of mass (COM) movement, which would normalize by the time of RTP but worsen after resuming activity. Methods: 13 adolescent concussion patients (7 male; age 10-17 years) were prospectively evaluated at their initial visit (IV) (mean 18, range 4-43 days post-concussion), at RTP clearance (mean 46, range 12-173 days post-concussion), and one month later (mean 26, range 20-41 days post-RTP) along with 11 controls (3 male) seen for similarly timed visits. Standing balance was assessed using range and root mean squared (RMS) COM motion in the anterior-posterior (AP) and ML directions during standing on both legs with eyes open while performing quiet standing, dual-task audio Stroop, side-to-side head turns, and side-to-side thumb tracking tasks. Dynamic balance was assessed using walking speed and COM ML range and velocity during walking alone and with side-to-side head turns and verbal fluency (reciting words starting with “F”) dual tasks. Patients were compared against controls using t-tests, and changes over time were evaluated using linear mixed-effects regression. Results: During standing, patients had higher COM ML RMS than controls at IV during head turns and higher COM AP range during thumb tracking. COM ML motion decreased from IV to RTP (head turns range -6.5mm, p=0.058; head turns RMS -16.8mm, p=0.002; thumb range 9.2mm, p=0.012) and increased from RTP to 1 month follow-up (head turns RMS +10.0mm, p=0.040; Stroop RMS +8.4mm, p=0.086). Patients walked slower than controls at IV during all tasks, and COM ML range was higher in patients vs. controls during verbal fluency at IV and RTP. Walking speed increased from IV to RTP during verbal fluency (+7.8cm/s, p=0.044), from RTP to post-RTP in single task walking (+6.1cm/s, p=0.041), and at each successive visit during head turns (+6.0cm/s and +6.5cm/s, p<0.07). COM ML range also decreased in patients from IV to RTP with verbal fluency (-14.7mm, p=0.011) and from RTP to post-RTP in single task walking ( 4.0mm, p=0.061). Conclusion: Adolescent concussion patients had deficits in static and dynamic balance control at initial presentation. This tended to improve by RTP and only worsened post-RTP for dual-task ML control during standing, suggesting that current conservative treatment protocols are appropriate.

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Driving Reaction Time Versus Computerized Reaction Time Deficits Following Concussion: Implications for Return to Driving Recommendations

Neurology ◽

10.1212/01.wnl.0000719904.59469.7c ◽

2020 ◽

Vol 95 (20 Supplement 1) ◽

pp. S5.1-S5

Author(s):

Landon Bryce Lempke ◽

Robert Lynall ◽

Nicole Hoffman ◽

Hannes Devos ◽

Julianne Schmidt

Keyword(s):

Reaction Time ◽

Pearson Correlation ◽

Vital Signs ◽

Correlation Coefficients ◽

Direct Methods ◽

Driving Safety ◽

Cross Sectional ◽

Driving Experience ◽

Simulated Driving ◽

And Control

ObjectiveTo compare simulated driving reaction time (RT) between concussed and control individuals and examine Driving-RTs relationship with computerized neurocognitive testing RT (CNT-RT).BackgroundConcussed patients have impaired RT and neurocognition following injury that may linger and impair driving performance. Limited research has used direct methods to assess driving-RT post-concussion.Design/MethodsWe employed a cross-sectional laboratory study among 14 concussed and 14 healthy age, sex, and driving experience-matched controls (female: 60%; Age: 20.3 ± 1.1 years). Participants completed driving-RT and CNT-RT (CNS Vital Signs) within 48 hours of asymptomatic (15.9 ± 9.8 days post-concussion). Driving-RT consisted of two simulated driving scenarios: Stoplight (green to yellow stoplight change) and Pedestrian (child running in front of vehicle). CNT-RT outcomes included: simple-, complex-, Stroop-, and composite-RT. Independent t-tests and Hedges' g effect sizes assessed between-group RT differences (seconds), and Pearson correlation coefficients examined relationships between driving-RT and CNT-RT (a = 0.05) outcomes.ResultsConcussed participants demonstrated slower complex-RT than controls (mean difference: 0.06 s; 95% CI: 0.11–0.01; p = 0.03; g = 0.86). No other driving- or CNT-RT outcomes were statistically significant (p = 0.06), but Stoplight- (p = 0.13; g = 0.61) and Pedestrian-RT (p = 0.40; g = 0.36) demonstrated low-to high-magnitude effects for concussed deficits. Complex-, Stroop-, and composite-RT moderately correlated with Stoplight-RT (p 0.05; r range: −0.19 to 0.05).ConclusionsPost-concussion driving- and CNT-RT outcomes overall normalized once asymptomatic, but complex-RT and large magnitude effects may indicate lingering deficits. Driving- and CNT-RT measures moderately correlated with each other, but a lack of strong correlation likely indicates driving responsiveness is not thoroughly assessed using traditional CNT post-concussion, which may have vital driving safety implications.

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Balance Performance With a Cognitive Task: A Continuation of the Dual-Task Testing Paradigm

Journal of Athletic Training ◽

10.4085/1062-6050-46.2.170 ◽

2011 ◽

Vol 46 (2) ◽

pp. 170-175 ◽

Cited By ~ 39

Author(s):

Jacob E. Resch ◽

Bryson May ◽

Phillip D. Tomporowski ◽

Michael S. Ferrara

Keyword(s):

Cognitive Processing ◽

Dual Task ◽

Repeated Measures ◽

Cognitive Task ◽

Return To Play ◽

Sensory Organization Test ◽

Sensory Organization ◽

Balance Task ◽

Visual Reference ◽

Task Conditions

Abstract Context: To ensure that concussed athletes return to play safely, we need better methods of measuring concussion severity and monitoring concussion resolution. Objective: To develop a dual-task model that assesses postural stability and cognitive processing in concussed athletes. Design: Repeated measures study. Setting: University laboratory. Patients or Other Participants: Twenty healthy, college-aged students (10 men, 10 women; age = 20 ± 1.86 years, height = 173 ± 4.10 cm, mass = 71.83 + 35.77 kg). Intervention(s): Participants were tested individually in 2 sessions separated by 2 days. In one session, a balance task and a cognitive task were performed separately. In the other session, the balance and cognitive tasks were performed concurrently. The balance task consisted of 6 conditions of the Sensory Organization Test performed on the NeuroCom Smart Balance Master. The cognitive task consisted of an auditory switch task (3 trials per condition, 60 seconds per trial). Main Outcome Measure(s): For the balance test, scores for each Sensory Organization Test condition; the visual, vestibular, somatosensory, and visual-conflict subscores; and the composite balance score were calculated. For the cognitive task, response time and accuracy were measured. Results: Balance improved during 2 dual-task conditions: fixed support and fixed visual reference (t18 = −2.34, P < .05) and fixed support and sway visual reference (t18 = −2.72, P = .014). Participants' response times were longer (F1,18 = 67.77, P < .001, η2 = 0.79) and choice errors were more numerous under dual-task conditions than under single-task conditions (F1,18 = 5.58, P = .03, η2 = 0.24). However, differences were observed only during category-switch trials. Conclusions: Balance was either maintained or improved under dual-task conditions. Thus, postural control took priority over cognitive processing when the tasks were performed concurrently. Furthermore, dual-task conditions can isolate specific mental processes that may be useful for evaluating concussed individuals.

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Single-Task and Dual-Task Gait Among Collegiate Athletes of Different Sport Classifications: Implications for Concussion Management

Journal of Applied Biomechanics ◽

10.1123/jab.2015-0323 ◽

2017 ◽

Vol 33 (1) ◽

pp. 24-31 ◽

Cited By ~ 27

Author(s):

David R. Howell ◽

Jessie R. Oldham ◽

Melissa DiFabio ◽

Srikant Vallabhajosula ◽

Eric E. Hall ◽

...

Keyword(s):

Task Performance ◽

Dual Task ◽

Inertial Sensors ◽

Cognitive Task ◽

Collegiate Athletes ◽

Gait Pattern ◽

Cognitive Test ◽

Single Task ◽

Gait Performance ◽

Cognitive Task Performance

Gait impairments have been documented following sport-related concussion. Whether preexisting gait pattern differences exist among athletes who participate in different sport classifications, however, remains unclear. Dual-task gait examinations probe the simultaneous performance of everyday tasks (ie, walking and thinking), and can quantify gait performance using inertial sensors. The purpose of this study was to compare the single-task and dual-task gait performance of collision/contact and noncontact athletes. A group of collegiate athletes (n = 265) were tested before their season at 3 institutions (mean age= 19.1 ± 1.1 years). All participants stood still (single-task standing) and walked while simultaneously completing a cognitive test (dual-task gait), and completed walking trials without the cognitive test (single-task gait). Spatial-temporal gait parameters were compared between collision/contact and noncontact athletes using MANCOVAs; cognitive task performance was compared using ANCOVAs. No significant single-task or dual-task gait differences were found between collision/contact and noncontact athletes. Noncontact athletes demonstrated higher cognitive task accuracy during single-task standing (P = .001) and dual-task gait conditions (P = .02) than collision/contact athletes. These data demonstrate the utility of a dual-task gait assessment outside of a laboratory and suggest that preinjury cognitive task performance during dual-tasks may differ between athletes of different sport classifications.

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Reduction of Dual-task Costs by Noninvasive Modulation of Prefrontal Activity in Healthy Elders

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00897 ◽

2016 ◽

Vol 28 (2) ◽

pp. 275-281 ◽

Cited By ~ 39

Author(s):

Brad Manor ◽

Junhong Zhou ◽

Azizah Jor'dan ◽

Jue Zhang ◽

Jing Fang ◽

...

Keyword(s):

Older Adults ◽

Dual Task ◽

Cognitive Task ◽

Brain Regions ◽

Dual Tasking ◽

Single Task ◽

Novel Approach ◽

Before And After ◽

Improved Performance ◽

Task Conditions

Dual tasking (e.g., walking or standing while performing a cognitive task) disrupts performance in one or both tasks, and such dual-task costs increase with aging into senescence. Dual tasking activates a network of brain regions including pFC. We therefore hypothesized that facilitation of prefrontal cortical activity via transcranial direct current stimulation (tDCS) would reduce dual-task costs in older adults. Thirty-seven healthy older adults completed two visits during which dual tasking was assessed before and after 20 min of real or sham tDCS targeting the left pFC. Trials of single-task standing, walking, and verbalized serial subtractions were completed, along with dual-task trials of standing or walking while performing serial subtractions. Dual-task costs were calculated as the percent change in markers of gait and postural control and serial subtraction performance, from single to dual tasking. Significant dual-task costs to standing, walking, and serial subtraction performance were observed before tDCS (p < .01). These dual-task costs were less after real tDCS as compared with sham tDCS as well as compared with either pre-tDCS condition (p < .03). Further analyses indicated that tDCS did not alter single task performance but instead improved performance solely within dual-task conditions (p < .02). These results demonstrate that dual tasking can be improved by modulating prefrontal activity, thus indicating that dual-task decrements are modifiable and may not necessarily reflect an obligatory consequence of aging. Moreover, tDCS may ultimately serve as a novel approach to preserving dual-task capacity into senescence.

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Effects of dual-task gait treadmill training on gait ability, dual-task interference, and fall efficacy in people with stroke: A Randomized Controlled Trial

Physical Therapy ◽

10.1093/ptj/pzab067 ◽

2021 ◽

Author(s):

Chang Yoon Baek ◽

Woo Nam Chang ◽

Beom Yeol Park ◽

Kyoung Bo Lee ◽

Kyoung Yee Kang ◽

...

Keyword(s):

Dual Task ◽

Cognitive Task ◽

Gait Training ◽

Control Group ◽

Task Condition ◽

Dual Task Condition ◽

Single Task ◽

Gait Parameters ◽

Task Training ◽

Task Conditions

Abstract Objective This study aimed to investigate the effects of dual-task gait training using a treadmill on gait ability, dual-task interference, and fall efficacy in people with stroke. Methods Patients with chronic stroke (N = 34) were recruited and randomly allocated to the experimental or control group. Both groups underwent gait training on a treadmill and a cognitive task. In the experimental group, gait training was conducted in conjunction with the cognitive task, whereas in the control group, the training and the cognitive task were conducted separately. Each intervention was provided for 60 minutes, twice a week, for a period of 6 weeks for both groups. The primary outcomes were as follows: gait parameters (speed, stride, variability, and cadence) under single-task and dual-task conditions, correct response rate (CRR) under single-task and dual-task conditions, and dual-task cost (DTC) in gait parameters and CRR. The secondary outcome was the fall efficacy scale. Results Dual-task gait training using a treadmill improved all gait parameters in the dual-task condition, speed, stride, and variability in the single-task condition, and CRR in both conditions. Difference between the groups was observed in speed, stride, and variability in the dual-task condition. Furthermore, dual-task gait training on a treadmill improved DTC in speed, variability, and cadence along with that in CRR, indicating true improvement of DTC, which led to significant improvement in DTC in speed and variability compared with single-task training. Conclusions Dual-task gait treadmill training was more effective in improving gait ability in dual-task training and DTI than single-task training involving gait and cognitive task separately in people with chronic stroke.

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