Until recently, gait was generally viewed as a largely automated motor task, requiring minimal higher-level cognitive input. Increasing evidence, however, links alterations in executive function and attention to gait disturbances. This review discusses the role of executive function and of attention in healthy walking and gait disorders while summarizing the relevant, recent literature. We describe the variety of gait disorders that may be associated with different aspects of executive function, and discuss the changes occurring in executive function as a result of aging and disease as well the potential impact of these changes on gait. The attentional demands of gait are often tested using dual tasking methodologies. Relevant studies in healthy adults and patients are presented, as are the possible mechanisms responsible for the deterioration of gait during dual tasking. Lastly, we suggest how assessments of executive function and attention could be applied in the clinical setting as part of the process of identifying and understanding gait disorders and fall risk.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/mds.21720

The role of executive function and attention in gait

Background Gait and cognitive disturbances are common in Parkinson's disease (PD). These deficits exacerbate fall risk and difficulties with mobility, especially during complex or dual-task walking. Traditional gait training generally fails to fully address these complex gait activities. Virtual reality (VR) incorporates principles of motor learning while delivering engaging and challenging training in complex environments. We hypothesized that VR may be applied to address the multifaceted deficits associated with fall risk in PD. Methods Twenty patients received 18 sessions (3 per week) of progressive intensive treadmill training with virtual obstacles (TT + VR). Outcome measures included gait under usual-walking and dual-task conditions and while negotiating physical obstacles. Cognitive function and functional performance were also assessed. Results Patients were 67.1 ± 6.5 years and had a mean disease duration of 9.8 ± 5.6 years. Posttraining, gait speed significantly improved during usual walking, during dual task, and while negotiating overground obstacles. Dual-task gait variability decreased (ie, improved) and Trail Making Test times (parts A and B) improved. Gains in functional performance measures and retention effects, 1 month later, were also observed. Conclusions To our knowledge, this is the first time that TT + VR has been used for gait training in PD. The results indicate that TT + VR is viable in PD and may significantly improve physical performance, gait during complex challenging conditions, and even certain aspects of cognitive function. These findings have important implications for understanding motor learning in the presence of PD and for treating fall risk in PD, aging, and others who share a heightened risk of falls.

/pdf/virtual-reality-for-gait-training-can-it-induce-motor-2kp9mqceb3.pdf

Virtual Reality for Gait Training: Can It Induce Motor Learning to Enhance Complex Walking and Reduce Fall Risk in Patients With Parkinson's Disease?

Objective:Return-to-play (RTP) decisions are fundamental to the practice of sports medicine but vary greatly for the same medical condition and circumstance. Although there are published articles that identify individual components that go into these decisions, there exists neither quantitative crit

https://www.fitasaphysio.com/uploads/4/3/3/4/43345381/return-to-play_in_sport-_a_decision-based_model.pdf

Return-to-play in sport: a decision-based model.

Previous studies suggest that strat- egies such as ''posture first'' are implicitly employed to regulate safety when healthy adults walk while simulta- neously performing another task, whereas ''posture sec- ond'' may be inappropriately applied in the presence of neurological disease. However, recent understandings raise questions about the traditional resource allocation concept during walking while dual tasking. We propose a task prioritization model of walking while dual tasking that integrates motor and cognitive capabilities, focus- ing on postural reserve, hazard estimation, and other individual intrinsic factors. The proposed prioritization model provides a theoretical foundation for future stud- ies and a framework for the development of interven- tions designed to reduce the profound negative impacts of dual tasking on gait and fall risk in patients with neu- rological diseases. V C 2012 Movement Disorder Society

Do we always prioritize balance when walking? Towards an integrated model of task prioritization

Recent studies have concluded that most individuals who sustain minor head injury are free of persistent neuropsychological dysfunction. Nevertheless, a subgroup of patients experience continuing post-concussive difficulties and neuropsychological deficits. This study examined 53 symptomatic minor head injury patients referred for neuropsychological evaluation between one and 22 months after injury. These individuals performed significantly poorer than uninjured controls on four of eight neuropsychological tests. Patients who lost consciousness during injury obtained test scores similar to persons who experienced disorientation or confusion but no loss of consciousness. The results indicate that minor head injury patients who report post-concussive symptoms possess measurable neuropsychological deficits and the severity of these deficits is independent of neurological status immediately following injury.

Neuropsychological deficits in symptomatic minor head injury patients after concussion and mild concussion

Objective To begin to understand changes in locomotor navigation in elite athletes following concussion. Methods Clinical measures and gait analysis were undertaken on average 37.33 days (SD = 4.8) postconcussion for 6 athletes as well as for a control group of athletes matched for age, sex, and team. The locomotor task consisted of walking at a self-selected speed along an unobstructed or obstructed path with and without a visual interference task. The trends for 4 dependent variables were described (2 for gait behavior and 2 for cognitive behavior). A principal component analysis was used to reduce data to root sources of variance among these variables. General group differences were tested with Wilcoxon matched-pairs tests on factorial scores. Results Athletes with concussion were symptom free at the time of testing and their neuropsychological test results were not different from those of athletes in the control group. However, when the laboratory data between paired groups were compared, descriptive analyses suggested potential group differences in navigating the obstacle. The simultaneous Stroop task appeared to present difficulty for both groups. A significant group effect was found on the component of the factorial analysis that was highly loaded with both gait and cognitive variables (minimum clearance, Stroop task errors, and cognitive dual-task costs), generally supporting the descriptive analyses by suggesting that athletes with concussion do not navigate the targeted complex environments like the control group. Conclusions Athletes with concussion appear to still show navigational deficits in environments well after being considered fully recovered according to current return-to-play protocols. Although still preliminary and requiring further study, the present findings suggest that functional assessment within complex environment contexts could be considered before sending athletes back to play following a concussion, even in the absence of postconcussion symptoms or with normal clinical outcomes.

Altered integrated locomotor and cognitive function in elite athletes 30 days postconcussion: a preliminary study.

https://www.archives-pmr.org/article/S0003-9993(06)00200-0/pdf

Effects of environmental demands on locomotion after traumatic brain injury.

Primary objective: To compare the locomotor capacity during (1) unobstructed walking and (2) the circumvention of fixed obstacles with and without a simultaneous visual task in an elite athlete before and after a sports-related concussion.Research design: Case report.Methods and procedures: Gait analysis and clinical neuropsychological measures were taken pre- and at 7 and 30 days post-injury in an 18 year old male junior hockey player. The task consisted of walking along an unobstructed or obstructed path with or without a visual interference task. Measurements included dual tasks costs, response errors, maximal gait speed and minimal clearance with the obstacle.Main outcome and results: Although the athlete was symptom-free and neuropsychological test results returned to baseline relatively quickly, he showed continued errors in the interference task, abnormally small obstacle clearance distances and decreased maximal gait speed up to 30 days after the concussion.Conclusions: Concussion can result in pe...

Alterations to locomotor navigation in a complex environment at 7 and 30 days following a concussion in an elite athlete.

Primary objective: To determine the relationships between clinical measures of executive function and attention, and laboratory measures of anticipatory locomotor adaptations with dual tasks following a TBI.Methods and procedures: Ten people with moderate or severe TBI were compared to 10 healthy subjects for neuropsychological measures in the clinic, as well as locomotor patterns and reading time in the laboratory for adapted Stroop tasks (Bar and Word) during unobstructed and obstructed walking.Main outcomes and results: As previously found (Vallee M, McFadyen BJ, Swaine B, Doyon J, Cantin JF, Dumas D. Effects of environmental demands on locomotion after traumatic brain injury. Archives of Physical Medicine Rehabilitation 2006;87:806--813) during the locomotor activities, subjects with TBI walked slower, had higher clearance margins and took longer to read during the Stroop tasks than healthy subjects. In general, subjects with TBI also showed deficits in executive functions and attention. Significant r...

Can measures of cognitive function predict locomotor behaviour in complex environments following a traumatic brain injury

https://www.archives-pmr.org/article/S0003-9993(09)00345-1/pdf

Jean-François Cantin

Papers

Altered integrated locomotor and cognitive function in elite athletes 30 days postconcussion: a preliminary study.

Effects of environmental demands on locomotion after traumatic brain injury.

Alterations to locomotor navigation in a complex environment at 7 and 30 days following a concussion in an elite athlete.

Can measures of cognitive function predict locomotor behaviour in complex environments following a traumatic brain injury

Modality-Specific, Multitask Locomotor Deficits Persist Despite Good Recovery After a Traumatic Brain Injury