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In emergency medical services (EMS), response time is a key factor that shows the performance of the system. This factor is composed of two parts including activation time and travel time. The activation time of an emergency call is the time a call center spends on taking an incoming call for EMS and decides whether an ambulance should be dispatched or the emergency can be resolved by giving some medical advices. Having a good number of call center operators including call takers and dispatchers can help to reduce this time and thus the response time. However, this alone may not be enough to have a reasonable cycle time. In fact, having idle ambulances located in right places when emergency calls occur is an influential factor to reduce the travel time and thus have an optimal response time and save people's lives. Although many researchers have studied improving either the activation time or the travel time, to the best of our knowledge, there exists no study focusing on both. Motivated by this gap, in this study, a framework is proposed which uses queuing theory and location analysis to address both activation and travel times. In this regard, first, queuing theory is applied to evaluate the performance of an EMS call center and reduce the average activation time. Then, three mathematical models including mobile stations, MEXCLP and MECRP are applied to locate ambulances such that the average travel time is minimized. To shed light on the merits of using queuing theory and location models, computational results based on the real-world data from Tehran EMS Center are provided. The proposed methodology can reduce the average response time by approximately four minutes and increase the average coverage by 35%. This work is an example of the tremendous positive impact that the application of queuing theory and mathematical modeling can have. The proposed framework can significantly decrease the cycle time and increase the ambulance coverage level. The findings of this study help the policy makers of EMS centers with evaluating the performance of their systems and determining the optimal number of operators and locations of ambulances in a way that enhances the quality of emergency services.

PURPOSE To assess early visual outcomes and military task performance after small-incision lenticule extraction (SMILE) among U.S. military service members. SETTING Warfighter Refractive Eye Surgery Program and Research Center and Night Vision and Electronic Sensors Directorate, Fort Belvoir, Virginia. DESIGN Single-center, prospective, observational study. METHODS The study was composed of active duty service members (n = 37) electing to undergo SMILE for myopia or myopic astigmatism. Testing performed preoperatively and at 1 month and 3 months postoperatively included uncorrected (UDVA) and corrected (CDVA) distance visual acuities, wavefront aberrometry, low-contrast visual acuity (LCVA), contrast sensitivity, and vision-related questionnaire. 14 participants underwent rifle marksmanship with spectacle correction before and without correction at 6 to 8 weeks postoperatively. RESULTS At 3 months postoperatively, the efficacy index was 0.96 and the safety index was 1.03. UDVA was ≥20/20 in 69 (96%) of eyes. LCVA change from baseline was significant under night vision condition. Eye problems contributed to 10% work and 20% activity impairments, both of which decreased to 0% (P = .001). The overall satisfaction rating for SMILE was high at 90.9 (95% CI, 85.3 to 96.5), and 95% of participants would be willing to undergo the procedure again. The median scores between preoperative and 6 to 8 weeks postoperative firing performance were comparable (34 vs 35, with and without correction, respectively; P = .247). CONCLUSIONS After the early recovery period, SMILE seems to preserve quality of vision, which appears to facilitate the accomplishment of tasks related to their work as military service members as well as performing activities outside of work.

Background Falls in older adults are considered a major public health problem. Declines in cognitive and physical functions, as measured by parameters including reaction time, mobility, and dual-task performance, have been reported to be important risk factors for falls. The aim of this study was to investigate the effects of two multimodal programs on reaction time, mobility, and dual-task performance in community-dwelling older adults at risk of falling. Methods In this randomized controlled trial, fifty-one participants (75.4 ± 5.6 years) were allocated into two experimental groups (EGs) (with sessions 3 times per week for 24 weeks), and a control group: EG1 was enrolled in a psychomotor intervention program, EG2 was enrolled in a combined exercise program (psychomotor intervention program + whole-body vibration program), and the control group maintained their usual daily activities. The participants were assessed at baseline, after the intervention, and after a 12-week no-intervention follow-up period. Results The comparisons revealed significant improvements in mobility and dual-task performance after the intervention in EG1, while there were improvements in reaction time, mobility, and dual-task performance in EG2 (p ≤ 0.05). The size of the interventions’ clinical effect was medium in EG1 and ranged from medium to large in EG2. The comparisons also showed a reduction in the fall rate in both EGs (EG1: -44.2%; EG2: − 63.0%, p ≤ 0.05) from baseline to post-intervention. The interventions’ effects on reaction time, mobility, and dual-task performance were no longer evident after the 12-week no-intervention follow-up period. Conclusions The results suggest that multimodal psychomotor programs were well tolerated by community-dwelling older adults and were effective for fall prevention, as well as for the prevention of cognitive and physical functional decline, particularly if the programs are combined with whole-body vibration exercise. The discontinuation of these programs could lead to the fast reversal of the positive outcomes achieved. Trial registration ClinicalTrials.gov Identifier: NCT03446352. Date of registration: February 07, 2018.

Objective To examine the individual and combined effects of daytime sleepiness and insomnia disorder (ID) on measures of cognitive functioning. Design and setting This study was conducted at a medical center using a cross-sectional research design. Participants 35 persons with ID (Mage = 40.6 years; 25 women) and 54 normal sleepers (NS; Mage = 31.5 years; 38 women). Methods and measures Participants underwent two nights of home-based polysomnography (PSG) followed by daytime testing with a four-trial Multiple Sleep Latency Test (MSLT). Before each MSLT nap, they completed a computer-administered battery of reaction time tasks. Measures of response latencies and response accuracy were tabulated and used as dependent measures. The ID and NS groups were each subdivided into “alert” (eg, MSLT mean latency > 8 min) and “sleepy” (eg, MSLT mean latency ≤ 8 min) subgroups to identify hyperaroused persons with ID and allow for their comparisons with the other participant subgroups. Results Multivariate analyses of variance showed a significant main effect for level of daytime sleepiness (F [1, 84] = 8.52, p = 0.0045) on simpler performance tasks and a significant main effect for presence vs. absence of ID (F [1,84] = 6.62, p = 0.012) on complex tasks. A lack of significant participant type x MSLT alertness level interactions in study analyses suggested those ID participants with presumed hyperaousal were not relatively more impaired than the other participant subgroups. Conclusions Daytime performance deficits on simple tasks seem most dependent on individuals’ levels of daytime sleepiness, whereas performance deficits on more complex tasks appears related to the presence of ID. Therefore, it seems best to use complex performance measures both to document cognitive deficits among those with ID and to determine if insomnia treatments reduce such impairments. Trial registration ClinicalTrials.gov Identifier: NCT02290405.

Background This investigation examined whether aspects of attention and executive functioning differed between Parkinson's Disease (PD) patients with freezing of gait (FOG) based on responsiveness to dopamine. We also explored association of cognition with FOG severity and gait metrics. Methods Fifty-four individuals with PD completed the study protocol: 17 without freezing (PDC), 23 with dopa-responsive FOG (RFOG), and 14 with dopa-unresponsive (URFOG). Standardized neuropsychological tests assessed attention (focused and sustained), psychomotor speed, and set-switching (time and errors). FOG severity was measured using the new FOG Questionnaire (nFOG-Q). Metrics from timed up and go (TUG) tasks were obtained while “on” and “off” dopamine, with and without dual cognitive tasks. Results After controlling for clinical and demographic factors, analysis of covariance revealed a significant between-group difference for set-switching errors; planned contrasts revealed increased set-switching errors in URFOG relative to RFOG and PD control groups. Groups were not different in other cognitive domains. FOG severity was modestly associated with set-switching errors in RFOG but not URFOG. TUG performances while “on” were associated with set-switching errors in PD controls, and with focused attention in RFOG. Conclusion PD patients with dopa-unresponsive FOG are more prone to set-switching errors than those who respond to treatment. Furthermore, executive function appears relevant to FOG severity only in patients who show dopamine response. Together, these findings suggest disruption of a common dopamine-mediated pathway for FOG and ability to monitor rules while alternating cognitive processes. Consideration of dopa-response could be useful in characterizing cohorts and treating FOG in PD.

Spiering, BA, Walker, LA, Larcom, K, Frykman, PN, Allison, SC, and Sharp, MA. Predicting soldier task performance from physical fitness tests: reliability and construct validity of a soldier task test battery. J Strength Cond Res 35(10): 2749-2755, 2021-The purpose of this study was to determine the reliability and construct validity of a battery of tests designed to assess soldier task performance. In the first part of the study (designed to assess test-retest reliability), 33 enlisted soldiers (31 men, 2 women; 23 ± 3 years; 1.75 ± 0.08 m; and 81.4 ± 12.8 kg) completed a 4-event "soldier task test battery" (STTB) on 4 occasions, each separated by at least 1 week. The STTB consisted of the following tests, in order: (a) 30-m grenade throw for accuracy; (b) running long jump while wearing a 20.5-kg load; (c) 1 repetition maximum box lift; and (d) 3.2-km load carriage time trial while wearing a 33-kg load. In the second part of the study (designed to assess construct validity), 41 male soldiers (22 ± 3 years; 1.75 ± 0.08 m; and 81.4 ± 12.9 kg) completed the STTB and a series of physical fitness tests. The physical fitness tests included measurements of body composition, muscular strength, muscular power, muscular endurance, and cardiovascular endurance. Overall performance on the STTB (reflected by the sum of z-scores across individual tests) demonstrated an intraclass correlation coefficient of 0.95 and was correlated to lean mass, V˙o2peak, and measures of muscular strength and power. Lean body mass and standing long jump predicted performance on the STTB (R2 = 0.41). In conclusion, this STTB can reliably assess performance of soldiering tasks. The relationships between the STTB and physical fitness tests can be used to develop training programs to prepare soldiers to perform physically demanding tasks.

Arsenic (As) toxicity has deleterious effects on human health causing disorder in the brain. The aim of this study was to investigate the possible neuroprotective effect of resveratrol (RSV) on arsenic-induced neurotoxicity in rats. Neurotoxicity in rats was developed by treating As 10 mg/kg/day for 21 days orally. Animals were put into seven groups: control, vehicle, As, As+RSV10, As+RSV20 mg/kg, RSV10, and RSV20 mg/kg. Behavioral assessments such as the social interaction test, novel object recognition test, elevated plus maze, open field, the Morris water maze, in addition to assessment of biomarkers such as ferric reducing ability of plasma assay, glutathione assay, and malondialdehyde assay, were used to evaluate the effects of RSV on cognitive impairment and molecular changes induced by As. The results showed that cognitive performance impaired in As rats. RSV20 mg/kg significantly could ameliorate behavioral changes like spatial learning in days 3 and 4 ( p < 0.05 ), recognition learning and memory ( p < 0.01 ), disabilities in motor coordination and stress ( p < 0.05 ), increased anxiety ( p < 0.05 ), and social interaction deficit (sociability ( p < 0.001 ) and social memory ( p < 0.05 )). RSV20 mg/kg also attenuated molecular modifications like decreased antioxidant power ( p < 0.001 ), reduced glutathione content ( p < 0.05 ), and increased malondialdehyde level ( p < 0.05 ) induced by As. In addition to oxidative stress assessments, RSV10 mg/kg could significantly increase FRAP ( p < 0.01 ) and GSH ( p < 0.05 ); however, MDA was not significantly increased. Our current behavioral findings suggest that RSV has neuroprotective effects against AS toxicity.

Extracellular recordings are typically analysed by separating them into two distinct signals: local field potentials (LFPs) and spikes. Previous studies have shown that spikes, in the form of single-unit activity (SUA) or multiunit activity (MUA), can be inferred solely from LFPs with moderately good accuracy. SUA and MUA are typically extracted via threshold-based technique which may not be reliable when the recordings exhibit a low signal-to-noise ratio (SNR). Another type of spiking activity, referred to as entire spiking activity (ESA), can be extracted by a threshold-less, fast, and automated technique and has led to better performance in several tasks. However, its relationship with the LFPs has not been investigated. In this study, we aim to address this issue by inferring ESA from LFPs intracortically recorded from the motor cortex area of three monkeys performing different tasks. Results from long-term recording sessions and across subjects revealed that ESA can be inferred from LFPs with good accuracy. On average, the inference performance of ESA was consistently and significantly higher than those of SUA and MUA. In addition, local motor potential (LMP) was found to be the most predictive feature. The overall results indicate that LFPs contain substantial information about spiking activity, particularly ESA. This could be useful for understanding LFP-spike relationship and for the development of LFP-based BMIs.

Objectives Explore the impact transitioning from daytime to nighttime operations has on performance in U.S. Army Rangers. Methods Fifty-four male Rangers (age 26.1 ± 4.0 years) completed the Y-Balance Test (YBT), a vertical jump assessment, and a grip strength test at three time points. Baseline testing occurred while the Rangers were on daytime operations; post-test occurred after the first night into the nighttime operation training (after full night of sleep loss), and follow-up testing occurred six days later (end of nighttime training). Results On the YBT, performance was significantly worse at post-test compared to baseline during right posteromedial reach (104.1 ± 7.2 cm vs 106.5 ± 6.7 cm, p = .014), left posteromedial reach (105.4 ± 7.5 cm vs 108.5 ± 6.6 cm, p = .003), right composite score (274.8 ± 19.3 cm vs 279.7 ± 18.1 cm, p = .043), left composite score (277.9 ± 18.1 cm vs 283.3 ± 16.7 cm, p = .016), and leg asymmetry was significantly worse in the posterolateral direction (4.8 ± 4.0 cm vs 3.7 ± 3.1 cm, p = .030) and the anterior direction (5.0 ± 4.0 cm vs 3.6 ± 2.6 cm, p = .040). The average vertical jump height was significantly lower at post-test compared to baseline (20.6 ± 3.4 in vs 21.8 ± 3.0 in, p = .004). Baseline performance on YBT and vertical jump did not differ from follow-up. Conclusions Army Rangers experienced an immediate, but temporary, drop in dynamic balance and vertical jump performance when transitioning from daytime to nighttime operations. When feasible, Rangers should consider adjusting their sleep cycles prior to anticipating nighttime operations in order to maintain their performance levels. Investigating strategies that may limit impairments during this transition is warranted.

The present study uniquely examined the influence of old age and adiposity on maximal concentric and eccentric torque and fatigue of the elbow and knee (KF, KE) flexors and extensors. Forty males were recruited and categorised into young (n = 21, 23.7 ± 3.4) and old (n = 19, 68.3 ± 6.1) and then further into normal (young = 16.9 ± 2.5%, old = 20.6 ± 3.1%) and high adiposity (young = 28.9 ± 5.0%, old = 31.3 ± 4.2%) groups. Handgrip strength, sit-to-stand performance, and isokinetic assessments of peak torque at 60°, 120° and 180°·s−1 were measured. Older men produced significantly less concentric and eccentric peak torque (P < 0.016) but this was not influenced by adiposity (P > 0.055). For KE and KF, high adiposity groups demonstrated reduced peak torque normalised to body mass (P < 0.021), and muscle and contractile mode specific reduction in torque normalised to segmental lean mass. Eccentric fatigue resistance was unaffected by both age and adiposity (P > 0.30) and perceived muscle soreness, measured up to 72 hours after, was only enhanced in the upper body of the young group following eccentric fatigue (P = 0.009). Despite the impact of adiposity on skeletal muscle function being comparable between ages, these results suggest high adiposity will have greater impact on functional performance of older adults. Novelty: Irrespective of age, high adiposity may negatively impact force to body mass ratio and muscle quality in a muscle and contractile mode specific manner. Whilst the magnitude of adiposity effects is similar across ages, the impact for older adults will be more substantial given the age-related decline in muscle function.

The round house kick (RHK) is a common technique in taekwondo (TKD). The kicking action originates from the dynamic stability of the pivot leg. However, some knee injuries are caused by more difficult kicking strategies, such as kicks to the opponent’s head. This study analyses the effects on TKD players in the lower extremity kinematic and neuromuscular reactions from different kicking heights. This study recruited 12 TKD players (age = 20.3 ± 1.3 years, height = 1.72 ± 0.09 m, mass = 62.17 ± 9.45 kg) with no previous lower extremity ligament injuries. All athletes randomly performed 3 RHK at different heights (head, chest, and abdomen), repeating each kick 5 times. During the RHK action, the kinematics and muscle activations of the pivot leg were collected using six high-speed cameras and electromyography devices. The results found that during the RHK return period a high kicking position demonstrated larger knee valgus with the straight knee, and more hamstring activation on the pivot leg. The RHK pivot foot for TKD players encountered more risk of injury from high target kicking. The hamstring muscle played an important stabilizing role. It is recommended that sports medicine clinicians or sports coaches use this information to provide further protective injury prevention strategies.

Purpose Monthly hormonal fluctuation in women causes changes in peripheral systems and central nervous system structure and functions. In this study, we investigated the effects of menstrual cycle periods in women on attention during multitasking. Single and dual task conditions were tested in different menstrual cycle periods. Materials and methods A total of forty women with regular menstrual cycles participated in this study. They were not any type of medication or hormonal treatment. Fine motor skills and Go/No-go tasks were performed on the 10th day of the late follicular phase, and then the tests were repeated on the 20th day of the late luteal phase. Fine motor tasks were performed by Annett's peg-moving test. Auditory stimuli were used in Go/No-go task. In dual tasks, both tasks were performed simultaneously. Results There was no difference between follicular and luteal phases in single fine motor and Go/No-go task. In dual task condition Go/No-go task % error rate decreased in the luteal phase. Similarly, Go/No-go task reaction time decreased in the luteal phase. Non-dominant hand performance was increased in the luteal phase during the dual-task condition compared to the follicular phase. Conclusions When these results are evaluated together, declining error rates and reaction times indicates women successfully multitask in the luteal phase in dual tasks condition. This suggests that divided attention in women leads to better performance in the luteal phase than in the follicular phase.

Objective Identify a critical research gap for the human factors community that has implications for successful human–automation teaming. Background There are a variety of approaches for applying automation in systems. Flexible application of automation such that its level and/or type changes during system operations has been shown to enhance human–automation system performance. Method This mini-review describes flexible automation in which the level of automated support varies across tasks during system operation, rather than remaining fixed. Two types distinguish the locus of authority to change automation level: adaptable automation (the human operator assigns how automation is applied) has been found to aid human’s situation awareness and provide more perceived control versus adaptive automation (the system assigns automation level) that may impose less workload and attentional demands by automatically adjusting levels in response to changes in one or more states of the human, task, environment, and so on. Results In contrast to vast investments in adaptive automation approaches, limited research has been devoted to adaptable automation. Experiments directly comparing adaptable and adaptive automation are particularly scant. These few studies show that adaptable automation was not only preferred over adaptive automation, but it also resulted in improved task performance and, notably, less perceived workload. Conclusion Systematic research examining adaptable automation is overdue, including hybrid approaches with adaptive automation. Specific recommendations for further research are provided. Application Adaptable automation together with effective human-factored interface designs to establish working agreements are key to enabling human–automation teaming in future complex systems.

Recent work has highlighted that people who have had TIA may have abnormal motor and cognitive function. We aimed to quantify deficits in a cohort of individuals who had TIA and measured changes in their abilities to perform behavioural tasks over 1 year of follow-up using the Kinarm Exoskeleton robot. We additionally considered performance and change over time in an active control cohort of migraineurs. Individuals who had TIA or migraine completed 8 behavioural tasks that assessed cognition as well as motor and sensory functionality in the arm. Participants in the TIA cohort were assessed at 2, 6, 12, and 52 weeks after symptom resolution. Migraineurs were assessed at 2 and 52 weeks after symptom resolution. We measured overall performance on each task using an aggregate metric called Task Score and quantified any significant change in performance including the potential influence of learning. We recruited 48 individuals to the TIA cohort and 28 individuals to the migraine cohort. Individuals in both groups displayed impairments on robotic tasks within 2 weeks of symptom cessation and also at approximately 1 year after symptom cessation, most commonly in tests of cognitive-motor integration. Up to 51.3% of people in the TIA cohort demonstrated an impairment on a given task within 2-weeks of symptom resolution, and up to 27.3% had an impairment after 1 year. In the migraine group, these numbers were 37.5% and 31.6%, respectively. We identified that up to 18% of participants in the TIA group, and up to 10% in the migraine group, displayed impairments that persisted for up to 1 year after symptom resolution. Finally, we determined that a subset of both cohorts (25–30%) experienced statistically significant deteriorations in performance after 1 year. People who have experienced transient neurological symptoms, such as those that arise from TIA or migraine, may continue to experience lasting neurological impairments. Most individuals had relatively stable task performance over time, with some impairments persisting for up to 1 year. However, some individuals demonstrated substantial changes in performance, which highlights the heterogeneity of these neurological disorders. These findings demonstrate the need to consider factors that contribute to lasting neurological impairment, approaches that could be developed to alleviate the lasting effects of TIA or migraine, and the need to consider individual neurological status, even following transient neurological symptoms.

The purpose of the current study was to examine the relationship between expertise, performance, and gaze behavior in a complex error-detection cockpit task. Twenty-four pilots and 26 non-pilots viewed video-clips from a pilot’s viewpoint and were asked to detect malfunctions in the cockpit instrument panel. Compared to non-pilots, pilots detected more malfunctioning instruments, had shorter dwell times on the instruments, made more transitions, visited task-relevant areas more often, and dwelled longer on the areas between the instruments. These results provide evidence for three theories that explain underlying processes for expert performance: The long-term working memory theory, the information-reduction hypothesis, and the holistic model of image perception. In addition, the results for generic attentional skills indicated a higher capability to switch between global and local information processing in pilots compared to non-pilots. Taken together, the results suggest that gaze behavior as well as other generic skills may provide important information concerning underlying processes that can explain successful performance during flight in expert pilots. ispartof: PLoS One vol:13 issue:11 ispartof: location:United States status: Published online

Stroke is one of the leading causes of death and the primary cause of acquired disability worldwide. Many stroke survivors have difficulty using their upper limbs, which have important functional roles in the performance of daily life activities. Consequently, the independence and quality of life of most stroke patients are reduced. Robot-assisted therapy is an effective intervention for improving the upper limb function of individuals with stroke. Human-robot collaborative interaction force control technology is critical for improving the flexibility and followability of the robot’s motion, thereby improving rehabilitation training outcomes. However, there are few reports on the effect of robot-assisted rehabilitative training on upper limb function. We applied this technology using a robot to assist patients with task-oriented training. Posttreatment changes in Fugl-Meyer and modified Barthel index (MBI) scores were assessed to determine whether this technology could improve the upper limb function of stroke patients. One healthy adult and five stroke patients, respectively, participated in functional and clinical experiments. The MBI and Fugl-Meyer scores of the five patients in the clinical experiments showed significant improvements after the intervention. The experimental results indicate that human-robot collaborative interaction force control technology is valuable for improving robots’ properties and patients’ recovery. This trial was registered in the Chinese clinical trial registry (ChiCTR2000038676).

Over the past 30 years, there have been numerous, noteworthy successes in the development, validation, and implementation of clinical skills assessments. Despite this progress, the medical profession has barely scratched the surface towards developing assessments that capture the true complexity of hands-on skills in procedural medicine. This paper highlights the development implementation and new discoveries in performance metrics when using sensor technology to assess cognitive and technical aspects of hands-on skills.

Hospital medicine groups vary staffing models to match available workforce with expected patient volumes and acuity. Larger groups often assign a single hospitalist to triage pager duty which can be burdensome due to frequent interruptions and multitasking. We introduced a new role, the Triage nurse, to hold the triage pager and distribute patients. We sought to determine the effect of this Triage Nurse on the perceived workload of hospitalists and frequency of pages.We partnered with our patient throughput department to implement the Triage Nurse role who took the responsibility of tracking and distributing admissions among three admitting physicians along with coordinating report. We used the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) to measure perceived workload and accessed pager logs of admitters for 3 months before and after implementation.Overall, 50 of an expected 67 NASA-TLX surveys (74.6%) were returned in the pre-intervention period and 64 of 92 (69.6%) were returned in the post-intervention period. We found a statistically significant reduction in the domains of physical demand, temporal demand, effort and frustration from pre- to post-intervention periods (p 0.01). There was also a significant decrease in the performance domain (p = 0.01) with a lower number indicative of better perceived performance. There was a significant reduction in the mean number of pages received by admitting hospitalists over their 9-h shifts (81.3 + 17.3 vs 52.4 + 7.3; p 0.01).The implementation of the Triage Nurse role was associated with a significant decrease in the perceived workload of admitting hospitalists. Our findings are important because workload and interruptions can contribute to errors and burnout. Future studies should test interventions to improve hospitalist workload and evaluate their effect on patient outcomes and physician wellness.

Although humans can direct their attention to visual targets with or without eye movements, it remains unclear how different brain mechanisms control visual attention and eye movements together and/or separately. Here, we measured MEG and fMRI data during covert/overt visual pursuit tasks and estimated cortical currents using our previously developed extra-dipole, hierarchical Bayesian method. Then, we predicted the time series of target positions and velocities from the estimated cortical currents of each task using a sparse machine-learning algorithm. The predicted target positions/velocities had high temporal correlations with actual visual target kinetics. Additionally, we investigated the generalization ability of predictive models among three conditions: control, covert, and overt pursuit tasks. When training and testing data were the same tasks, the largest reconstructed accuracies were overt, followed by covert and control, in that order. When training and testing data were selected from different tasks, accuracies were in reverse order. These results are well explained by the assumption that predictive models consist of combinations of three computational brain functions: visual information-processing, maintenance of attention, and eye-movement control. Our results indicate that separate subsets of neurons in the same cortical regions control visual attention and eye movements differently.

Serotonin (5-HT) is a key neuromodulator of medial prefrontal cortex (mPFC) functions. Pharmacological manipulation of systemic 5-HT bioavailability alters the electrical activity of mPFC neurons. However, 5-HT modulation at the population level is not well characterized. In the present study, we made single neuron extracellular recordings in the mPFC of rats performing an operant conditioning task, and analyzed the effect of systemic administration of fluoxetine (a selective serotonin reuptake inhibitor) on the information encoded in the firing activity of the neural population. Chronic (longer than 15 days), but not acute (less than 15 days), fluoxetine administration reduced the firing rate of mPFC neurons. Moreover, fluoxetine treatment enhanced pairwise entropy but diminished noise correlation and redundancy in the information encoded, thus showing how mPFC differentially encodes information as a function of 5-HT bioavailability. Information about the occurrence of the reward-predictive stimulus was maximized during reward consumption, around 3 to 4 s after the presentation of the cue, and it was higher under chronic fluoxetine treatment. However, the encoded information was less robust to noise corruption when compared to control conditions.

The aim of the study was to determine the impact of dual-task conditions on mobility after mild traumatic brain injury.Eleven adults with mild traumatic brain injury within 1 wk of injury and 10 age- and sex-matched healthy controls completed gait trials with a single-task condition and three separate dual-task conditions: counting by 1 (low), serial subtraction by 3 (medium), and alternating letters and numbers (high). Dual-task cost was calculated as dual-task cost = ([dual-task performance] - [single-task performance]) / [single-task performance] × 100%.Participants with mild traumatic brain injury ambulated slower than control subjects (P0.001). Significant differences in dual-task cost were noted for both group (P0.001) and dual-task condition (P = 0.005). Dual-task cost was greater for those with mild traumatic brain injury compared with controls with significant group differences for the low and high cognitive loads (P0.05). Only 1 of the 11 individuals with mild traumatic brain injury and 1 of the 10 controls demonstrated gait speed less than 80 cm/sec, which is predictive of community mobility, during any dual-task condition. Dual-task cost exceeded 11.9%, previously determined to be the minimal detectable change in healthy adults, for 9 of the 11 individuals with mild traumatic brain injury compared with 3 of the 10 controls.Dual-task cost may be a more sensitive measure for impairment during dual-task conditions than gait speed after mild traumatic brain injury.

Background Within surgery, assistive robotic devices (ARD) have reported improved patient outcomes. ARD can offer the surgical team a “third hand” to perform wider tasks and more degrees of motion in comparison with conventional laparoscopy. We test an eye-tracking based robotic scrub nurse (RSN) in a simulated operating room based on a novel real-time framework for theatre-wide 3D gaze localization in a mobile fashion. Methods Surgeons performed segmental resection of pig colon and handsewn end-to-end anastomosis while wearing eye-tracking glasses (ETG) assisted by distributed RGB-D motion sensors. To select instruments, surgeons (ST) fixed their gaze on a screen, initiating the RSN to pick up and transfer the item. Comparison was made between the task with the assistance of a human scrub nurse (HSNt) versus the task with the assistance of robotic and human scrub nurse (R&HSNt). Task load (NASA-TLX), technology acceptance (Van der Laan’s), metric data on performance and team communication were measured. Results Overall, 10 ST participated. NASA-TLX feedback for ST on HSNt vs R&HSNt usage revealed no significant difference in mental, physical or temporal demands and no change in task performance. ST reported significantly higher frustration score with R&HSNt. Van der Laan’s scores showed positive usefulness and satisfaction scores in using the RSN. No significant difference in operating time was observed. Conclusions We report initial findings of our eye-tracking based RSN. This enables mobile, unrestricted hands-free human–robot interaction intra-operatively. Importantly, this platform is deemed non-inferior to HSNt and accepted by ST and HSN test users.

Functional magnetic resonance imaging (fMRI) has significant potential to evaluate changes in brain network activity after traumatic brain injury (TBI) and enable early prognosis of potential functional (e.g., motor, cognitive, behavior) deficits. In this study, resting-state and task-based fMRI (rs- and tb-fMRI) were utilized to examine network changes in a pediatric porcine TBI model that has increased predictive potential in the development of novel therapies. rs- and tb-fMRI were performed one day post-TBI in piglets. Activation maps were generated using group independent component analysis (ICA) and sparse dictionary learning (sDL). Activation maps were compared to pig reference functional connectivity atlases and evaluated using Pearson spatial correlation coefficients and mean ratios. Nonparametric permutation analyses were used to determine significantly different activation areas between the TBI and healthy control groups. Significantly lower Pearson values and mean ratios were observed in the visual, executive control, and sensorimotor networks for TBI piglets compared to controls. Significant differences were also observed within several specific individual anatomical structures within each network. In conclusion, both rs- and tb-fMRI demonstrate the ability to detect functional connectivity disruptions in a translational TBI piglet model, and these disruptions can be traced to specific affected anatomical structures.

This review aimed to investigate characteristics of muscle activation and ground reaction force (GRF) patterns in patients with ankle instability (AI). Relevant studies were sourced from PubMed, CINAHL, SPORTDiscus, and Web of Science through December 2019 for case-control study in any laboratory setting. Inclusion criteria for study selection were (1) subjects with chronic, functional, or mechanical instability or recurrent ankle sprains; (2) primary outcomes consisted of muscle activation of the lower extremity and GRF during landing; and (3) peer-reviewed articles with full text available, including mean, standard deviation, and sample size, to enable data reanalysis. We evaluated four variables related to landing task: (1) muscle activation of the lower extremity before landing, (2) muscle activation of the lower extremity during landing, (3) magnitude of GRF, and (4) time to peak GRF. The effect size using standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated for these variables to make comparisons across studies. Patients with AI had a lower activation of peroneal muscles before landing (SMD = -0.63, p 0.05). Altered muscle activation and GRF before and during landing in AI cases may contribute to both recurrent ankle and ACL injuries and degenerative change of articular. Key points Patients with ankle instability have a lower activation of peroneal muscles before landing. Additionally, patients with ankle instability have greater peak vertical GRF and shorter time to peak vertical GRF than those of normal subjects during landing. Altered landing strategy in cases of ankle instability may contribute both to the recurrent ankle and other injuries of the lower extremity (e.g., ACL tear and degenerative change of articular cartilage).

To assess the efficacy of a motion-sensing, hands-free gaming device and task-oriented training (TOT) programs on improving hand function, activity performance, and satisfaction in pediatric hand burns.A randomized controlled trial.Outpatient rehabilitation center.Fifty children with deep partial-thickness or full-thickness hand burns. (N=50; mean age, 10.70±1.64y; range, 7-14y) INTERVENTIONS: Children were randomized into 1 of the following 3 groups: the motion-sensing, hands-free gaming device group that used interactive video games plus traditional rehabilitation (TR); the TOT group that used real materials plus TR; and the control group that only received TR, all groups received the interventions 3 days per week for 8 weeks.We assessed the children at the baseline and after 8 weeks of intervention. The primary outcome measures were the Jebsen-Taylor Hand Function Test, Duruoz Hand Index (DHI), and Canadian Occupational Performance Measure (COPM). The secondary outcome measures were range of motion (ROM) of the digits, grip strength, and pinch strengths (tip, palmer, and lateral pinch).There was a significant increase in all measurements of the motion-sensing, hands-free gaming device and TOT groups compared with that of the control group postintervention (P.05). There was no significant change in Jebsen-Taylor Hand Function Test, COPM performance, ROM, grip strength, and tip and lateral pinch strengths between the motion-sensing, hands-free gaming device group and TOT group (P.05), whereas there was a significant increase in DHI, COPM satisfaction, and palmer pinch strength (P.05) in the motion-sensing, hands-free gaming device group compared with the TOT group postintervention.The motion-sensing, hands-free gaming device and TOT programs resulted in significant improvement in hand function, activity performance and satisfaction, ROM of the digits, grip strength, and pinch strengths in pediatric hand burns compared with the traditional hand rehabilitation.

Background Older persons with polypharmacy are at increased risk of harm from medications. Therefore, it is important that physicians and nurses, together with the persons, evaluate medications to avoid hazardous polypharmacy. It remains unclear how healthcare professionals experience such evaluations. This study aimed to explore physicians’ and nurses’ experiences from evaluations of older persons’ medications, and their related actions to manage concerns related to the evaluations. Method Individual interview data from 29 physicians and nurses were collected and analysed according to the critical incident technique. Results The medication evaluation for older persons was influenced by the working conditions (e.g. healthcare professionals’ clinical knowledge, experiences, and situational conditions) and working in partnership (e.g. cooperating around and with the older person). Actions taken to manage these evaluations were related to working with a plan (e.g. performing day-to-day work and planning for continued treatment) and collaborative problem-solving (e.g. finding a solution, involving the older person, and communicating with colleagues). Conclusion Working conditions and cooperation with colleagues, the older persons and their formal or informal caregivers, emerged as important factors related to the medication evaluation. By adjusting their performance to variations in these conditions, healthcare professionals contributed to the resilience of the healthcare system by its capacity to prevent, notice and mitigate medication problems. Based on these findings, we hypothesize that a joint plan for continued treatment could facilitate such resilience, if it articulates what to observe, when to act, who should act and what actions to take in case of deviations from what is expected.

Background: The Clinical Dementia Rating (CDR) scale is commonly used to stage cognitive impairment, despite having educational limitations. In elderly with low education, a previous study has shown that intraindividual variability of reaction time (CV) and commission errors (CE), measured using a culture-free Go/No-Go task, can reliably distinguish early Alzheimer’s disease (AD) from mild cognitive impairment (MCI) and healthy controls. Objective: We aimed to extend the clinical utility of this culture-free Go/No-Go task in a sample with high educational disparity. Methods: One hundred and ten participants with a wide range of years of formal education (0–14 years) were randomly selected from a geriatric unit and divided based on their CDR scores into cognitively unimpaired (CDR = 0), MCI (CDR = 0.5), and early AD (CDR = 1). All underwent a 90-s reaction-time test that measured the variables previously found to predict CDR in low educated elderly. Here we added years of formal education (educational level) to the model. Multivariate analyses compared differences in group means using educational level as confounding factor. A confirmatory discriminant analyses was performed, to assess if CDR scores could be predicted by the two Go/No-Go variables in a sample with high educational disparity. Results: Over all three groups, differences in both CE and CV reached statistical significance (p

Studies on the effects of acute exercises on cognitive functions vary greatly and depend on the duration and intensity of exercise and the type of cognitive tasks. This study aimed to investigate the neural correlates that underpin the acute effects of high-intensity interval (HIIE) versus moderate-intensity continuous exercise (MCE) on fine motor-cognitive performance while walking (dual-task, DT) in healthy young adults. Twenty-nine healthy right-handers (mean age: 25.1 years ± 4.04; 7 female) performed the digital trail-making-test (dTMT) while walking (5 km/h) before and after acute exercise. During task performance, the hemodynamic activation of the frontopolar area (FPA), dorsolateral prefrontal (DLPFC), and motor cortex (M1) was recorded using functional near-infrared spectroscopy (fNIRS). Both HIIE and MCE resulted in improved dTMT performance, as reflected by an increase in the number of completed circles and a reduction in the time within and between circuits (reflecting improvements in working memory, inhibition, and decision making). Notably, HIIE evoked higher cortical activity on all brain areas measured in the present study than the MCE group. To our knowledge, these results provide the first empirical evidence using a mobile neuroimaging approach that both HIIE and MCE improve executive function during walking, likely mediated by increased activation of the task-related area of the prefrontal cortex and the ability to effectively use, among other things, high fitness levels as neural enrichment resources.

Background The prevention of work-related musculoskeletal disorders (MSDs) is an important issue for the health of operators, especially when the workload is heavy, such as in drilling activities. Research question This study aimed to propose an objective identification and description of the different phases that comprise a drilling task as well as a biomechanical and ergonomic evaluation of the subjects' overall posture during its effective part. Methods Fourteen healthy subjects performed three successive drillings at two different heights, 130 (H130) and 170 cm (H170) from the ground, of a 3 mm thick steel plate. Kinematic and kinetic data were simultaneously acquired using a Qualisys motion capture system and a force platform. The speed profiles of each body segments and the evolution of the force exerted were analysed to identify the different phases. Then, the average joint angles of the whole body were calculated during the drilling phase for the two heights considered and compared. Finally, the measured postures were qualified through the Rapid Upper Limb Assessment (RULA) score in order to assess the risk of developing MSDs for each condition. Results The drilling task could be divided into five phases whatever the condition: transport, aiming, repositioning, drilling, and return. The increase in height has doubled the duration of the drilling phase while reducing the force exerted by about 30 %. Similarly, height variation significantly influenced the subjects' posture, mainly in the head, trunk and upper limbs, and the RULA scores obtained for conditions H130 and H170 were 6 and 7 respectively. Significance The results indicate, on the one hand, the relevance of coupling kinematic and kinetic data in order to analyse the drilling task and, on the other hand, that operators are exposed to considerable risk of developing MSDs, even at intermediate heights, which increase as the height increases.

Individual performance in controlling complex dynamic systems such as managing production in a company or keeping ecosystems in balance is often suboptimal. In this article, we provide the first unequivocal test of whether groups are superior to individuals when controlling dynamic systems. In addition, we test to what extent performance advantages of groups are simply the result of statistically aggregating a larger number of individual opinions and to what extent they represent true synergy attributable to within-group interaction. In 3 experiments, we compared the system control performance of interacting real groups with that of equally sized nominal groups and with individuals. We provide evidence that groups indeed perform better than individuals in dynamic system control tasks. Furthermore, in comparing real groups with nominal groups, we show that, although the majority of real groups' performance advantage stems from statistical aggregation, there is also evidence of true synergy. Finally, we identify the mechanism by which groups achieve synergy, namely group-to-individual transfer. Discussion allows group members to exchange critical information about the system, leading to an improved individual capability to control the system, which, in turn, improves group performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Reflectance, lighting and geometry combine in complex ways to create images. How do we disentangle these to perceive individual properties, such as surface glossiness? We suggest that brains disentangle properties by learning to model statistical structure in proximal images. To test this hypothesis, we trained unsupervised generative neural networks on renderings of glossy surfaces and compared their representations with human gloss judgements. The networks spontaneously cluster images according to distal properties such as reflectance and illumination, despite receiving no explicit information about these properties. Intriguingly, the resulting representations also predict the specific patterns of ‘successes’ and ‘errors’ in human perception. Linearly decoding specular reflectance from the model’s internal code predicts human gloss perception better than ground truth, supervised networks or control models, and it predicts, on an image-by-image basis, illusions of gloss perception caused by interactions between material, shape and lighting. Unsupervised learning may underlie many perceptual dimensions in vision and beyond., Storrs et al. train unsupervised generative neural networks on glossy surfaces and show how gloss perception in humans may emerge in an unsupervised fashion from learning to model statistical structure.

Funder: University of Melbourne; doi: http://dx.doi.org/10.13039/501100001782, The survival of human organisms depends on our ability to solve complex tasks in the face of limited cognitive resources. However, little is known about the factors that drive the complexity of those tasks. Here, building on insights from computational complexity theory, we quantify the computational hardness of cognitive tasks using a set of task-independent metrics related to the computational resource requirements of individual instances of a task. We then examine the relation between those metrics and human behavior and find that they predict both time spent on a task as well as accuracy in three canonical cognitive tasks. Our findings demonstrate that performance in cognitive tasks can be predicted based on generic metrics of their inherent computational hardness.

This study aimed to replicate Muir and Moray that demonstrated operators' trust in automated machines developing from faith, then dependability, and lastly predictability. Following the procedure of Muir and Moray, we asked undergraduate participants to complete a training program in a simulated pasteuriser plant and an experimental program including various errors in the pasteuriser. Results showed that the best predictor of overall trust was not faith but dependability, and that dependability consistently governed trust throughout the interaction with the pasteuriser. Thus, the obtained data patterns were inconsistent with those reported in Muir and Moray. We observed that operators in the current study used automatic control more frequently than manual control to successfully produce performance scores contrary to the operators in Muir and Moray. The results imply that dependability is a critical predictor of human-machine trust, which automation designer may focus on. More extensive future research using more modern automated technologies is necessary for understanding what factors control human-autonomy trust in modern ages.

This systematic review and meta-analysis determined resistance training (RT) load effects on various muscle hypertrophy, strength, and neuromuscular performance task [e.g., countermovement jump (CMJ)] outcomes. Relevent studies comparing higher-load [60% 1-repetition maximum (RM) or15-RM] and lower-load (≤60% 1-RM or ≥ 15-RM) RT were identified, with 45 studies (from 4713 total) included in the meta-analysis. Higher- and lower-load RT induced similar muscle hypertrophy at the whole-body (lean/fat-free mass; [ES (95% CI) = 0.05 (-0.20 to 0.29)

Background/objective: Constant pain causes suffering and affects performance of activities of daily living (ADL). In clients with chronic musculoskeletal pain, we wanted to determine (i) the relationship between the perceived burden of suffering (measured with the Pictorial Representation of Illness and Self Measure (PRISM)) and the observed quality of ADL task performance (measured with the Assessment of Motor and Process Skills (AMPS)); and (ii) the change in these assessments before and after a 12-week pain programme. Methods: In this cross-sectional cohort study, we retrospectively collected data from participants in a Swiss pain management programme. We calculated the relationship, correlations and effect sizes for the PRISM and AMPS using non-parametric tests. We set the level of significance at α = 0.05. Results: Out of 138 clients, 74 participated. We found no significant correlations between the PRISM and AMPS (p = 0.55–0.36), except for the PRISM and AMPS process ability measure after the pain management programme (p = 0.023). Pre-post-correlations of the AMPS and PRISM were significant, with medium to strong effect sizes (−0.48–0.66). Conclusion: Participation in this pain programme improved both, the PRISM and AMPS scores. The lack of correlation between these assessments in clients with chronic musculoskeletal pain, however, strongly argues for a thorough clinical assessment.

This study aimed to investigate the dual-task cost of both motor and cognitive performances in patients with multiple sclerosis (PwMS) and in healthy controls and to determine their relationships with clinical features in PwMS. The participants performed motor tasks (postural stability, walking, and manual dexterity) and cognitive tasks (mental tracking and verbal fluency) under single- and dual-task conditions. The results showed that postural stability under dual-task conditions did not change, whereas walking and manual dexterity deteriorated, regardless of the concurrent cognitive task, in PwMS (median Expanded Disability Status Scale score: 1) and the healthy controls. Verbal fluency decreased during postural stability, whereas it increased during walking, and it was maintained during manual dexterity in both groups. Mental tracking did not change during walking; it declined during manual dexterity in both groups. Mental tracking during postural stability deteriorated in PwMS, while it did not change in the healthy controls. In general, dual-task costs were associated with baseline performances of tasks rather than clinical features. Therefore, baseline performances of both tasks should be increased for improving dual-task performance in PwMS.

Competitive ski mountaineering (SKIMO) has achieved great popularity within the past years. However, knowledge about the predictors of performance and physiological response to SKIMO racing is limited. Therefore, 21 male SKIMO athletes split into two performance groups (elite: VO2max 71.2 ± 6.8 ml· min-1· kg-1 vs. sub-elite: 62.5 ± 4.7 ml· min-1· kg-1) were tested and analysed during a vertical SKIMO race simulation (523 m elevation gain) and in a laboratory SKIMO specific ramp test. In both cases, oxygen consumption (VO2), heart rate (HR), blood lactate and cycle characteristics were measured. During the race simulation, the elite athletes were approximately 5 min faster compared with the sub-elite (27:15 ± 1:16 min; 32:31 ± 2:13 min; p < 0.001). VO2 was higher for elite athletes during the race simulation (p = 0.046) and in the laboratory test at ventilatory threshold 2 (p = 0.005) and at maximum VO2 (p = 0.003). Laboratory maximum power output is displayed as treadmill speed and was higher for elite than sub-elite athletes (7.4 ± 0.3 km h-1; 6.6 ± 0.3 km h-1; p < 0.001). Lactate values were higher in the laboratory maximum ramp test than in the race simulation (p < 0.001). Pearson’s correlation coefficient between race time and performance parameters was highest for velocity and VO2 related parameters during the laboratory test (r > 0.6). Elite athletes showed their superiority in the race simulation as well as during the maximum ramp test. While HR analysis revealed a similar strain to both cohorts in both tests, the superiority can be explainable by higher VO2 and power output. To further push the performance of SKIMO athletes, the development of named factors like power output at maximum and ventilatory threshold 2 seems crucial.

Highlights • Single/dual-task tandem gait performance after concussion was slower than in controls. • Tandem gait cut-points provided > 80% accuracy between concussion and control groups. • Dual-task tandem gait test performance may provide some prognostic value., Background The tandem gait test has gained interest recently for assessment of concussion recovery. The purpose of our study was to determine the prognostic and diagnostic use of the single- and dual-task tandem gait test, alongside other clinical measures, within 10 days of pediatric concussion. Methods We assessed 126 patients post-concussion (6.3 ± 2.3 days post-injury, mean ± SD) at a pediatric sports medicine clinic and compared them to 58 healthy controls (age: 15.6 ± 1.3 years; 43% female). We also compared the 31 patients with concussion who developed persistent post-concussion symptoms (PPCS) (age = 14.9 ± 2.0 years; 48% female) to the 81 patients with concussion who did not develop PPCS following the initial assessment (age: 14.1 ± 3.0 years; 41% female). All subjects completed a test battery, and concussion patients were monitored until they experienced concussion-symptom resolution. The test battery included tandem gait (single-task, dual-task (performing tandem gait while concurrently completing a cognitive test) conditions), modified Balance Error Scoring System (mBESS), and concussion symptom assessment (Health and Behavior Inventory). We defined PPCS as symptom resolution time > 28 days post-concussion for the concussion group. Measurement outcomes included tandem gait time (single- and dual-task), dual-task cognitive accuracy, mBESS errors (single/double/tandem stances), and symptom severity. Results The concussion group completed the single-task (mean difference = 9.1 s, 95% confidential interval (95%CI): 6.1–12.1) and dual-task (mean difference = 12.7 s, 95%CI: 8.7–16.8) tandem gait test more slowly than the control group. Compared to those who recovered within 28 days of concussion, the PPCS group had slower dual-task tandem gait test times (mean difference = 7.9 s, 95%CI: 2.0–13.9), made more tandem-stance mBESS errors (mean difference = 1.3 errors, 95%CI: 0.2–2.3), and reported more severe symptoms (mean difference = 26.6 Health and Behavior Inventory rating, 95%CI: 21.1–32.6). Conclusion Worse dual-task tandem gait test time and mBESS tandem stance performance predicted PPCS in pediatric patients evaluated within 10 days of concussion. Tandem gait assessments may provide valuable information augmenting common clinical practices for concussion management., Graphical abstract Image, graphical abstract

Highlights • This review presents a conceptual framework linking motor control impairments after sport-related concussion (SRC) to elevated risk for lower extremity musculoskeletal injury. • Athletes with SRC demonstrate neuroanatomic and neurophysiologic changes relevant to motor control and altered motor function that support the conceptual framework. • Alterations in motor function after SRC include decreased muscle activation and force production, modified movement patterns, poor balance, and impaired motor task performance with or without a simultaneous cognitive task. • These deficits indicate a need to evaluate for and rehabilitate motor control impairments after SRC through the return to sport continuum to mitigate musculoskeletal injury risk., This review presents a conceptual framework and supporting evidence that links impaired motor control after sport-related concussion (SRC) to increased risk for musculoskeletal injury. Multiple studies have found that athletes who are post-SRC have higher risk for musculoskeletal injury compared to their counterparts. A small body of research suggests that impairments in motor control are associated with musculoskeletal injury risk. Motor control involves the perception and processing of sensory information and subsequent coordination of motor output within the central nervous system to perform a motor task. Motor control is inclusive of motor planning and motor learning. If sensory information is not accurately perceived or there is interference with sensory information processing and cognition, motor function will be altered, and an athlete may become vulnerable to injury during sport participation. Athletes with SRC show neuroanatomic and neurophysiological changes relevant to motor control even after meeting return to sport criteria, including a normal neurological examination, resolution of symptoms, and return to baseline function on traditional concussion testing. In conjunction, altered motor function is demonstrated after SRC in muscle activation and force production, movement patterns, balance/postural stability, and motor task performance, especially performance of a motor task paired with a cognitive task (i.e., dual-task condition). The clinical implications of this conceptual framework include a need to intentionally address motor control impairments after SRC to mitigate musculoskeletal injury risk and to monitor motor control as the athlete progresses through the return to sport continuum., Graphical abstract Image, graphical abstract

Within the operating rooms (ORs), distractions occur on a regular basis, which affect the surgical workflow and results in the interruption of urgent tasks. This study aimed to observe the occurrence of intraoperative distractions in Tunisian ORs and evaluate associations among distractions, teamwork, workload, and stress.This observational cross-sectional study was conducted in four different ORs (orthopedic, urology, emergency, and digestive surgery) of Sahloul University Hospital for a period of 3 mo in 2018. Distractions and teamwork were recorded and rated in real time during the intraoperative phase of each case using validated observation sheets. Besides, at the end of each operation, stress and workload of team members were measured.Altogether, 50 cases were observed and 160 participants were included. Distractions happened in 100% of the included operations. Overall, we recorded 933 distractions that occurred once every 3 min, with a mean frequency of M = 18.66 (standard deviation [SD] = 8.24) per case. It is particularly noticeable that procedural distractions occurred significantly higher during teaching cases compared with nonteaching cases (M = 3.85, M = 0.60, respectively, P 0.001). The mean global teamwork score was M = 3.85 (SD = 0.67), the mean workload score was M = 58.60 (SD = 24.27), and the mean stress score was M = 15.29 (SD = 4.00). Furthermore, a higher stress level among surgeons was associated with distractions related to equipment failures and people entering or exiting the OR (r = 0.206, P 0.01 and r = 0.137, P 0.01, respectively). Similarly, nurses reported a higher workload in the presence of distractions related to the work environment in the OR (r = 0.313, P 0.05).This study highlighted a serious problem, which often team members seem to ignore or underestimate. Taking our findings into consideration, we recommend the implementation of the Surgical Checklist and preoperative briefings to reduce the number of surgical distractions. Also, a continuous teamwork training should be adopted to ensure that OR staff can avoid or handle distractions when they happen.

Background Altered inter-joint coordination and reduced flexion-relaxation at end-range trunk flexion are common in people with low back pain. Inconsistencies in these behaviors, however, make assessment and treatment challenging for this population. Research question The study objective was to investigate patterns of regional lumbo-pelvic coordination and flexion-relaxation in adults with and without low back pain, during a bending task. Methods Adults with low back pain (n = 16) and a healthy group (n = 21) performed three trials of a bending task. Motion capture and surface electromyography systems measured joint kinematics (hip, lower and upper lumbar spine) and muscle activity (erector spinae longissimus, iliocostalis, and multifidus). Continuous relative phase analysis determined inter-joint coordination of the hip/lower lumbar and lower lumbar/upper lumbar joint pairs, during flexion and extension periods. Flexion-relaxation ratios using normalized surface electromyography data determined the extent of flexion-relaxation for each muscle, during each period. For inter-joint coordination, two-way repeated measure mixed ANOVAs calculated the effects of group (healthy/low back pain), period, and their interactions. Separate hierarchical linear models were constructed and tested relationships between flexion-relaxation ratios and our independent variables, group and muscle, while controlling for patient characteristics. Results The low back pain group had more out-of-phase coordination of the hip/lower lumbar joint pair compared to the healthy group (mean difference = 24.7°; 95 % confidence interval = 3.93–45.4), independent of movement period. No significant between group differences in lower lumbar/upper lumbar coordination were observed. The low back pain group demonstrated reduced flexion-relaxation of all muscles during full flexion (21.7 % reduction on average), with multifidus showing the least relaxation. Significance Regional differences in the lumbar spine and the possibility of subgroups with distinct movement pattern should be considered when analyzing coordination in people with low back pain. Multifidus showed the largest changes in flexion-relaxation and should be included when measuring this construct.

Purpose This study aimed 1) to determine whether talar cartilage deformation measured via ultrasonography (US) after standing and hopping loading protocols differs between chronic ankle instability (CAI) patients and healthy controls and 2) to determine whether the US measurement of cartilage deformation reflects viscoelasticity between standing and hopping protocols. Methods A total of 30 CAI and 30 controls participated. After a 60-min off-loading period, US images of the talar cartilage were acquired before and after static (2-min single-leg standing) and dynamic (60 single-leg forward hops) loading conditions. We calculated cartilage deformation by assessing the change in average thickness (mm) for overall, medial, and lateral talar cartilage. The independent variables include time (Pre60 and postloading), condition (standing and dynamic loading), and group (CAI and control). A three-way mixed-model repeated-measures ANCOVA and appropriate post hoc tests were used to compare cartilage deformation between the groups after static and dynamic loading. Results After the static loading condition, those with CAI had greater talar cartilage deformation compared with healthy individuals for overall (-10.87% vs -6.84%, P = 0.032) and medial (-12.98% vs -5.80%, P = 0.006) talar cartilage. Similarly, the CAI group had greater deformation relative to the control group for overall (-8.59% vs -3.46%, P = 0.038) and medial (-8.51% vs -3.31%, P = 0.043) talar cartilage after the dynamic loading condition. In the combined cohort, cartilage deformation was greater after static loading compared with dynamic in overall (-8.85% vs -6.03%, P = 0.003), medial (-9.38% vs -5.91%, P = 0.043), and lateral (-7.90% vs -5.65%, P = 0.009) cartilage. Conclusion US is capable of detecting differences in cartilage deformation between those with CAI and uninjured controls after standardized physiologic loads. Across both groups, our results demonstrate that static loading results in greater cartilage deformation compared with dynamic loading.

Objective To compare the prefrontal cortex (PFC) activation and task performance during single- and dual-task conditions between typically developing (TD) children and children with hemiplegic cerebral palsy (HCP). Design A prospective, comparative design. Setting Research laboratory. Participants Participants (N=21) included 12 TD children (age, 6.0±1.1y) and 9 children with HCP (age, 7.2±3.1). Interventions Not applicable. Main Outcome Measures PFC activation was assessed by measuring the concentration of oxygenated hemoglobin while the children performed a shape-matching task with their more affected arm while sitting on a stable (single task) vs dynamic surface (dual task). The task performance was assessed with the total number of shapes matched, dual-task cost, and reaction time (RT). Results For both conditions, the children with HCP exhibited greater PFC activation, matched a fewer shapes, and had slower RT than the TD children. These differences were accentuated during the dual-task condition and the dual-task cost was greater. An increase in the PFC activation during the dual-task condition was tightly correlated with a higher dual-task cost in children with HCP (r=0.77, P=.01). Conclusions Children with HCP appear to have a heightened amount of PFC activity while performing a dual task. The greater cortical activity may be a result of the finite attentional resources that are shared between both the motor as well as cognitive demands of the task. The cognitive-motor interference is likely exacerbated in children with HCP because of the structural and functional brain changes as a result of an insult to the developing brain.

Background Previous research demonstrated that manipulation of the extremities was associated with changes in multisegmental postural sway as well as improvement in a lower extremity balancing task. We were interested if these effects would extend to an upper extremity task. Our aim in this study was to investigate whether extremity manipulation could influence dual task performance where the explicit suprapostural task was balancing a water filled tube in the frontal plane. Methods Participants were healthy volunteers (aged 21–32 years). Upper- or lower-extremity manipulations were delivered in a participant and assessor blinded, randomized crossover, clinical trial. Postural (center of pressure) and suprapostural (tube motion) measurements in the frontal plane were made pre-post manipulation under eyes open and eyes closed conditions using a BTrackS™ force plate and a Shimmer inertial measurement unit, respectively. Pathlength, range, root mean square and sample entropy were calculated to describe each signal during the dual task performance. Results There was no main effect of manipulation or vision for the suprapostural task (tube motion). However, follow-up to interaction effects indicates that roll pathlength, range and root means square of tube motion all decreased (improvement) following lower extremity manipulation with eyes open. Regarding the postural task, there was a main effect of manipulation on mediolateral center of pressure such that pathlength reduced with both upper and lower extremity manipulation with larger decreases in pathlength values following upper extremity manipulation. Conclusion Our findings show that manipulation of the extremities enhanced stability (e.g. tube stabilization and standing balance) on performance of a dual task. This furthers the argument that site-specific manipulations influence context specific motor behavior/coordination. However, as this study focused only on the immediate effects of extremity manipulation, caution is urged in generalizing these results to longer time frames until more work has been done examining the length of time these effects last. Trial registration Clinicaltrials.gov, NCT03877367, Registered 15 March 2019. Data collection took place July 2019.

Background Gait impairments are common in patients with Alzheimer’s disease. Cholinesterase inhibitors are used to treat the symptoms of patients with Alzheimer’s disease, but they have not been shown to reduce the severity of Alzheimer’s disease-related gait disorders. Methods This was a prospective, single-arm, open-label, non-randomized study. The aim of the present study was to determine the effect of the acetylcholinesterase inhibitor rivastigmine on gait in 21 newly diagnosed patients with mild to moderate Alzheimer’s disease. The outcome variables were velocity, stride length, and cadence during single-task and dual-task gait trials. The subjects were also assessed with the Mini-Mental State Examination, Alzheimer’s Disease Cooperative Study Activities of Daily Living, Functional Assessment Staging, and Geriatric Depression Scale. Results After 12 weeks of treatment with rivastigmine, gait velocity was significantly improved in the dual-task gait trials; gait velocity was increased from 40.59 ± 13.59 m/min at baseline to 46.88 ± 12.73 m/min when counting backward from 100 in steps of 7 while walking, and gait velocity was increased from 37.06 ± 15.57 m/min at baseline to 42.03 ± 14.02 m/min when naming animals while walking. In the single-task gait trials, which consisted only of walking at their usual pace or at a fast pace, gait velocity was not increased by rivastigmine administration. Conclusion Our findings indicated that rivastigmine improved gait in subjects with mild to moderate Alzheimer’s disease during dual-task trials. The observed enhancement of dual-task gait might be caused by an improvement of cognitive function rather than motor function. Trial registration UMIN, UMIN000025869. Registered December 16, 2016, https://upload.umin.ac.jp/cgi-open-bin/icdr/ctr_view.cgi?recptno=R000029744

Objective The present study replicated and extended prior findings of suboptimal automation use in a signal detection task, benchmarking automation-aided performance to the predictions of several statistical models of collaborative decision making. Background Though automated decision aids can assist human operators to perform complex tasks, operators often use the aids suboptimally, achieving performance lower than statistically ideal. Method Participants performed a simulated security screening task requiring them to judge whether a target (a knife) was present or absent in a series of colored X-ray images of passenger baggage. They completed the task both with and without assistance from a 93%-reliable automated decision aid that provided a binary text diagnosis. A series of three experiments varied task characteristics including the timing of the aid’s judgment relative to the raw stimuli, target certainty, and target prevalence. Results and Conclusion Automation-aided performance fell closest to the predictions of the most suboptimal model under consideration, one which assumes the participant defers to the aid’s diagnosis with a probability of 50%. Performance was similar across experiments. Application Results suggest that human operators’ performance when undertaking a naturalistic search task falls far short of optimal and far lower than prior findings using an abstract signal detection task.

BackgroundMedical team leaders in cardiac arrest teams are routinely subjected to disproportionately high levels of cognitive burden. This simulation-based study explored whether the introduction of a dedicated ‘nursing team leader’ is an effective way of cognitively offloading medical team leaders of cardiac arrest teams. It was hypothesised that reduced cognitive load may allow medical team leaders to focus on high-level tasks resulting in improved team performance.MethodsThis randomised controlled trial used a series of in situ simulations performed in two Australian emergency departments in 2018–2019. Teams balanced on experience were randomised to either control (traditional roles) or intervention (designated nursing team leader) groups. No crossover between groups occurred with each participant taking part in a single simulation. Debriefing data were collected for thematic analysis and quantitative evaluation of self-reported cognitive load and task efficiency was evaluated using the NASA Task Load Index (NTLX) and a ‘task time checklist’ which was developed for this trial.ResultsTwenty adult cardiac arrest simulations (120 participants) were evaluated. Intervention group medical team leaders had significantly lower NTLX scores (238.4, 95% CI 192.0 to 284.7) than those in control groups (306.3, 95% CI 254.9 to 357.6; p=0.02). Intervention group medical team leaders working alongside a designated nursing leader role had significantly lower cognitive loads than their control group counterparts (206.4 vs 270.5, p=0.02). Teams with a designated nurse leader role had improved time to defibrillator application (23.5 s vs 59 s, p=0.004), faster correction of ineffective compressions (7.5 s vs 14 s, p=0.04), improved compression fraction (91.3 vs 89.9, p=0.048), and shorter time to address reversible causes (107.1 s vs 209.5 s, p=0.002).ConclusionDedicated nursing team leadership in simulation based cardiac arrest teams resulted in cognitive offload for medical leaders and improved team performance.

Given the rising incidence of stroke, several technology-driven methods for rehabilitation have recently been developed. Virtual reality (VR) is a promising therapeutic technology among them. We recently developed a neuroscientifically grounded VR system to aid recovery of motor function poststroke. The developed system provides unilateral and bilateral upper extremity (UE) training in a fully immersive virtual environment that may stimulate and activate mirror neurons (MNs) in the brain necessary for UE rehabilitation. Twenty-three participants were randomized to a VR group (n = 12) to receive VR intervention (8 h within 2 weeks) plus 8-h occupational therapy (OT) or a control group (n = 11) to receive time-matched OT alone. Treatment effects on motor recovery and cortical reorganization were investigated using the Barthel Index (BI), Fugl-Meyer Upper Extremity (FM-UE), and resting-state fMRI. Both groups significantly improved BI (P < 0.05), reflecting the recovery of UE motor function. The VR group revealed significant improvements on FM-UE scores (P < 0.05) than the control group. Neural activity increased after the intervention, particularly in the brain areas implicating MNs, such as in the primary motor cortex. Overall, results suggested that using a neuroscientifically grounded VR system might offer additional benefits for UE rehabilitation in patients receiving OT.

Background Objective Electronic health records (EHRs) are linked with documentation burden resulting in clinician burnout. While clear classifications and validated measures of burnout exist, documentation burden remains ill-defined and inconsistently measured. We aim to conduct a scoping review focused on identifying approaches to documentation burden measurement and their characteristics. Materials and Methods Based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Extension for Scoping Reviews (ScR) guidelines, we conducted a scoping review assessing MEDLINE, Embase, Web of Science, and CINAHL from inception to April 2020 for studies investigating documentation burden among physicians and nurses in ambulatory or inpatient settings. Two reviewers evaluated each potentially relevant study for inclusion/exclusion criteria. Results Of the 3482 articles retrieved, 35 studies met inclusion criteria. We identified 15 measurement characteristics, including 7 effort constructs: EHR usage and workload, clinical documentation/review, EHR work after hours and remotely, administrative tasks, cognitively cumbersome work, fragmentation of workflow, and patient interaction. We uncovered 4 time constructs: average time, proportion of time, timeliness of completion, activity rate, and 11 units of analysis. Only 45.0% of studies assessed the impact of EHRs on clinicians and/or patients and 40.0% mentioned clinician burnout. Discussion Standard and validated measures of documentation burden are lacking. While time and effort were the core concepts measured, there appears to be no consensus on the best approach nor degree of rigor to study documentation burden. Conclusion Further research is needed to reliably operationalize the concept of documentation burden, explore best practices for measurement, and standardize its use.