Organisers:

Melvyn Roerdink, Bert Coolen, Eva Hoogendoorn, Lotte Hardeman, Jorgen Ellis

Mixed reality, the integration of real and digital worlds, is the rising star in the virtuality continuum. A promising advance in that regard are untethered and transparent headsets equipped with a holographic display unit, like Microsoft HoloLens 2 and Magic Leap 2, through which 3D holograms are not only overlaid but anchored to and interacting with the wearer’s environment. This merging of real and digital worlds affords a realistic interaction with digital content during free movements in open environments.

The main goal of this mixed-reality workshop is to get attendees familiar with the basic principles of mixed reality and its potential for posture and gait research through lecture-like plenary presentations, each followed by a demo. What is mixed reality? How does it relate to virtual reality and augmented reality? How does it merge holographic content with the real world? What can I do with mixed reality?

The second goal is to offer attendees hands-on experience with mixed reality in a research context, with a focus on applications to persons with Parkinson’s disease, through four short presentations followed by interactive demos: 1) the eyes, the ears and the brains of mixed reality for motor-state dependent cueing applications, 2) progress in MR hardware in terms of wearer comfort and field of view, which improves the natural interaction with nearby digital objects, like cues and obstacles, 3) the feasibility of home-based gait-and-balance training with MR, remotely personalized for content and difficulty levels and 4) the transfer from academia to the real world focusing on public-private partnerships

After completing this workshop on mixed reality, attendees:

1. are acquainted with the basic principles of MR
2. can position MR in the virtuality continuum and relate it to VR and AR
3. are aware of the rich sensing abilities underlying MR and associated opportunities for posture and gait research in and outside the lab
4. are introduced to aspects relevant to motor-state dependent MR applications
5. have experienced leading mixed-reality hardware (Microsoft HoloLens and Magic Leap) themselves, as well as the progress made therein from the first to the second generation.
6. are introduced to the feasibility of MR studies in free-living environments (e.g., safety, user experience, adherence, potential efficacy for improving gait and balance)
7. are introduced to opportunities and obstacles of public-private partnership to transfer scientific findings to commercially available and/or clinically relevant products or interventions.

This workshop will be hosted by Gait and Posture and delivered by members of the editorial team. The workshop will cover the essential ingredients to writing and publishing a high-impact paper, covering topics such as what to include or not include in your paper, the importance of language, addressing the “so what” question, and how and why papers get cited. There will also be opportunity for Q&A to ask all your questions directly to our editors. This workshop is designed for the PhD-students, post-docs, and early career researchers, but we would like to extend this invitation to anyone within the ISPGR community who is interested in the topic.

Chair & Moderator:

Prof Stephen Lord, Neuroscience Research Australia

Presenters: 

Kim Delbaere¹, Toby Ellmers¹, Mei Ling (Mae) Lim¹, Will Young¹

¹Neuroscience Research Australia

Concerns about falling (CaF) are a global health issue affecting many older people, especially those who have had a fall and those with balance disorders (e.g. Parkinson’s Disease). CaF often result in a negative spiral of needless activity restriction and physical deconditioning, which can be problematic. About two-thirds of older people with CaF report avoiding activities due to these concerns; which subsequently leads to further decline in physical and cognitive function, poorer mental health, lower quality of life and increased risk for future falls. However, emerging evidence suggests that CaF may also be protective for some individuals. Recent theoretical developments highlight the crucial role that an individual’s cognitive response plays with respect to how CaF ultimately affects balance and safety. The 2022 World Falls Guidelines highlighted the importance of assessing and managing CaF to reduce fall risk of older people in different settings. The guidelines also revealed important gaps in the current literature, including the applicability of the Falls Efficacy Scale International (FES-I) to different settings and clinical populations. The guidelines recommended exercise, cognitive behavioural therapy (CBT) and/or occupational therapy to reduce CaF; however, the effects of these interventions were short-lasting. Emerging work on falls health literacy and digital programs could be the solution to offer long-term (self-)management of CaF. This symposium aims to discuss emerging work on CaF and future approaches to advance our knowledge in the area. We will provide a short overview of the recommendations from the 2022 World Falls Guidelines as the current evidence base for CaF in older people. The talks will then focus on “what’s next”: 1. A novel theoretical model will be presented to illustrate the complex relationship between falls health literacy and CaF and how falls health literacy can help improve the management of CaF in older people. 2. We will be challenged to “look beyond” CaF and consider the cognitive processes which mediate CaF and balance safety. 3. Issues regarding measuring and utilising anxiety-related outcomes in clinical settings, including the potential sources of bias in patient-reported outcomes relating to CaF instruments and the exploration of factors that contribute to one’s sense of control and how these can be influenced by various clinical diagnoses, will be shared. 4. The potential of combining potentially effective interventions (e.g. exercise with CBT) to generate larger effects on CaF and innovative approaches to managing CaF in older people will be discussed. This symposium will discuss the latest evidence and emerging topics in CaF that will shape future research directions. The symposium will prompt greater discussions about the current recommendations and how we can address CaF more effectively in clinical settings and achieve longer lasting effects on CaF in older people.

Chair:

Tanvi Bhatt, University of Illinois at Chicago

Moderator:

Vivian Weerdesteyn, Radboud University

Presenters:

Tanvi Bhatt¹, Daniel Peterson², Kelly Westlake³, Joris van der Cruijsen⁴

¹University of Illinois at Chicago, ²Arizona State University, ³University of Maryland, ⁴Radboud University Medical Center

The ability to release effective balance responses after a slip or trip is critical to prevent a fall. An understanding of the neural mechanisms that underlie these responses is important to the development of evidence based and targeted interventions. Early work in animal models has provided some insight into which portions of the brain likely contribute to this movement. Although the neural correlates of reactive balance control in humans are not fully clear, recent neuroimaging work has begun to shed light on how the brain controls this important movement. This talk will focus on how cortical and subcortical structures, such as the brainstem and basal ganglia (as well as their connections to other regions), and attentional and emotional networks, may contribute to reactive postural control. We will discuss recent neuroimaging investigations of the neural mechanisms underlying fear of falling and cognitive processes in relation to reactive balance outcomes. We will present evidence from neuroimaging techniques such as functional Near Infrared Spectroscopy (fNIRS), Magnetic Resonance Imaging (MRI) (Diffusion Tensor Imaging and functional MRI) and Electroencephalography (perturbation-based cortical evoked potentials). Finally, we will highlight ways by which neuroimaging can be used to inform clinical practice and fall prevention efforts in aging and neurological populations. After this talk, participants will be able to: a) describe how various brain regions contribute to reactive balance control in humans; b) describe different neuro imaging techniques and their pro and cons as it relates to examining reactive balance control; c) identify the neural processes that underlie fear of falling in relation to protective balance responses and d) describe ways by which neuroimaging can inform fall prevention rehabilitation efforts.

Chair:

S. Jayne Garland, Western University

Moderator:

Sandy Brauer, Head of School of Health and Rehabilitation Sciences, University of Queensland

Presenters:

Paul Hodges², Sue Peters¹, Jasmine Mirdamadi³, Jayne Garland¹

¹Western University, ²University of Queensland, ³Emory University

Background: Motor performance of posture and gait requires the integration of sensorimotor circuits involving the muscles, sensory organs, spinal cord, brainstem, and brain. Cortical involvement in balance and gait is often inferred through indirect and/or subjective assessments of motor behavior. Advances in methods to study brain function are providing new opportunities to; (i) understand the mechanisms underlying posture and gait dysfunction; (ii) evaluate brain function during function with cutting-edge mobile neuroimaging and electroencephalography; and (iii) modify brain function with non-invasive brain stimulation. These novel methodologies provide new opportunities to both explore and influence the recovery of motor function. Ultimately, any neuroplasticity in the brain would need to manifest itself in appropriate muscle activation patterns in balance and mobility tasks. These novel methodologies provide new opportunities to both explore and influence the recovery of motor function. Ultimately, this work aims to guide clinical practice and predict recovery of balance and gait. Aims: Research using these new and advanced methodologies aims to guide clinical practice and predict recovery of balance and gait. Yet, debate abounds regarding the clinical applicability of these lines of research. This symposium seeks to generate discussion around which (if any) tools for evaluation or stimulation of brain function have current and/or future clinical applicability to predicting outcomes or guiding interventions in balance and gait disorders produced by pain and neurological disorders, such as stroke. Relevance: Posture and gait are impacted in a diverse array of conditions from neurological disorders to chronic pain. Balance and gait declines with these disorders are complex and heterogenous, resulting in variable rehabilitation response efficacy. Advances in neuroimaging and non-invasive brain stimulation offer mechanistic insight into balance and gait function that may help predict fall risk, distinguish individual differences in function, and guide personalized rehabilitation interventions.

Chair:

Anne-Hélène Olivier Univ Rennes, Inria, M2S, VirtUs, Rennes, France

Moderator:

Michael Barnett-Cowan, Department of Kinesiology, University of Waterloo

Presenters:

Anne-Hélène Olivier¹, Anne-Hélène Olivier², Michael Cinelli³, Anouk Lamontagne⁴, Bradford McFadyen⁵, Melvin Roerdink⁶, Jorgen Ellis⁷

¹Univ Rennes, Inria, CNRS, IRISA, M2S, ²Univ Rennes, Inria, M2S, ³Wilfrid Laurier University, ⁴McGill University, Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR, ⁵CIRRIS/U Laval, ⁶Vrije Universiteit Amsterdam, ⁷Strolll

The ability to constantly adapt and accommodate our locomotion to the environment is crucial for safe mobility and social participation. While the study of basic locomotion has been greatly advanced, research on how it is adapted to and accommodated for the ever changing environment has received relatively less study. Yet, understanding adaptations of daily locomotion has been recently advanced through the integration of immersive technology (e.g., virtual reality or VR and augmented reality or AR) to more intricately manipulate environmental factors as well as better represent real life contexts in controlled experiments. This more ecological nature of immersive technology also provides the ability to safely expose patients to realistic locomotor-based scenarios earlier in their rehabilitation. While such rapidly evolving technology has enhanced fundamental and applied research, it also poses challenges to accessibility and acceptability in both research and practice, in particular for locomotor-based research where space is often an issue. It is therefore important to discuss the benefits, limitations and prospects of these emerging technologies as they are becoming more and more popular among researchers and clinicians interested in locomotor behaviour, including many ISPGR members. In this symposium, we will focus on recent use of VR and AR to study, assess, and create interventions on locomotor behaviour in cluttered environments. Thus, the objective of this symposium is twofold: first, it aims at conveying some of the recent research to understand locomotor navigation in cluttered environments using immersive technologies and the ways that some of this evidence has been used for clinical application; second, it aims at discussing (with the audience) the potential challenges and solutions for using immersive technology for basic and applied research focused on locomotor behaviour.

Chair & Moderator: 

Dr Morag Taylor, Falls, Balance and Injury Research Centre, Neuroscience Research Australia

Presenters:

Morag Taylor¹, Kim van Schooten¹, Lloyd Chan¹, Ngaire Kerse², Meghan Ambrens¹

¹Neuroscience Research Australia, University of New South Wales, ²Auckland University

Background: Walking is fundamental to effectively perform activities of daily living and maintain a good quality of life. Walking speed has been described as the 6th vital sign since it is reliable, valid and predicts many adverse health outcomes and conditions e.g. mortality, functional decline, dementia, falls hospitalisation and discharge location. The potential utility of digital gait monitoring for detecting elevated risk of adverse health outcomes (e.g. falls and mortality), as well as identifying the presence and worsening of medical conditions and diseases (e.g. depression and dementia), has been demonstrated. However, until recently, accelerometers were predominantly worn on the lumbar spine, were relatively expensive, required specialist software and involved complex procedures to extract and interpret data. These challenges have limited the utility of remote digital gait monitoring and contributed to the delay in translation from research to clinical practice. Aims: 1. Provide an overview of the utility of remote digital gait monitoring including current research evidence and gaps. 2. Provide examples of the potential utility of remote digital gait monitoring for clinical practice. 3. Identify facilitators and barriers to implementation and clinical translation of remote digital gait monitoring. 4. Provide an understanding of what is needed to facilitate implementation of remote digital gait monitoring from clinicians’ perspectives. Relevance: Remote digital gait monitoring offers advantages over clinic-based assessments. For example, a clinician is not required to setup, observe and measure gait, reduced ‘white-coat’ effect, improved accessibility and reach and regular and automated monitoring of performance. However, currently, the clinical use of remote digital gait monitoring is limited. Gait speed is simple, inexpensive to assess and sensitive and specific to health-related outcomes. While remote digital gait monitoring provides an extensive array of digital gait biomarkers, some of the positive attributes of more simple measurements are lacking. For digital gait biomarkers to be effectively implemented, they need to be as accessible and meaningful, for both patients and clinicians, as current measurement approaches. Additionally, remote digital gait monitoring does not currently align with clinician reimbursement models and technical support is often expensive. Wrist worn devices may help overcome some of these challenges and emerging research suggests reliable and valid algorithms can be developed to predict important health outcomes. It takes 17 years for research to be translated into practice, it is time to ensure future research is developed with an understanding of what clinicians and patients need and want, to expedite implementation of digital gait monitoring into clinical practice.

Chair & Moderator: 

W. Geoffrey Wright, Neuromotor Sciences Program, Health & Rehabilitation Sciences Dept., Temple University

Presenters:

W. Geoffrey Wright¹, Yury Ivanenko², Chris Thompson¹, Martin Zaback¹, Lena Ting³

¹Temple University, ²IRCCS Fondazione Santa Lucia, ³Emory and Georgia Tech University

Despite 150 years of clinical recognition that tonic drive is essential to healthy motor functioning, where tests of muscle tone are considered a sensitive sign for measuring CNS health, the heavy focus on phasic muscle activity in research has dominated the field of postural, locomotor, and fine motor control. Unquestionably, phasic neuromuscular control is important for postural stabilization, relying on short latency automatic and reflexive pathways. However, background tonic neuromuscular activity also plays an essential role in balance, as sustained fatigue-resistant muscle activity counteracts gravity and allows for unconscious control of numerous body segments to maintain stable posture. Muscle tone is thought to come from multiple descending and afferent sources, but the extent to which it arises from cortical, subcortical, spinal, or peripheral mechanisms remains unknown. This symposium brings together five researchers with unique approaches to investigating tonic neuromuscular processes, especially as they relate to postural and locomotor behavior. Lena Ting brings a unique perspective from systems engineering and neuroscience that combines multiscale modeling and experimental approaches to explain how tone affects muscle forces and sensory feedback essential for reactive postural control. Chris Thompson and Martin Zaback use a novel method of recording populations of motor units with high-density surface EMG to estimate persistent inward currents, which may provide a spinal level of postural tone. Yury Ivanenko explores the early manifestation and development of tone in infants learning to stand and walk. Geoff Wright looks at tone in the latter half of life, since it has been found to differ among healthy young, healthy old, and adults with rigidity. After presenting their research findings, the speakers will form a panel (4 panellists and 1 moderator) with audience participation to discuss whether balance requires both phasic and tonic muscle activity and where the source of muscle tone may arise.

Chair & Moderator:

Winfried Ilg, Hertie Institute for Clinical Brain Research, Tübingen, Germany; – Fay Horak, Department of Neurology, Oregon Health & Science University, Portland, US

Presenters:

Winfried Ilg¹, Martina Mancini², Lisa Alcock³, Riona Mc Ardle³

¹Hertie Institute for Clinical Brain Research, ²Oregon Health & Science University Portland, ³Newcastle University

Falls often occur while turning. The majority of tasks in the home require 3-4 turns and over 40% of daily steps are turning steps. In addition, when a fall occurs during a turn, it is 8 times more likely to result in a hip fracture. In fact, falls that occur while attempting a turn result in sideways falling to the ground, often onto the greater trochanter of the hip. A recent video analysis of the most common circumstances of falls in daily life in 130 elderly people residing in long-term care revealed that that 41% of 223 recorded falls occurred during turning. The majority of older individuals and people with neurological diseases have difficulty turning because of the complex interaction of gait with balance during turning. Turning may be a sensitive marker of early disease because it reflects complex neural control of dynamic balance, the ability to control the body center of mass (COM) with respect to the moving base of support. Turning safely requires the complex interaction of many neural processes: control of axial flexibility, adequate size and speed of steps, top-down coordination of eyes-head-trunk rotation, multisensory integration, motor planning, anticipatory postural adjustments, attention and set-switching, all of which are affected by aging, dementia, Parkinson’s disease, and spinocerebellar ataxia. In this symposium, we will present and discuss the most recent approaches of quantifying turning movements as a sensitive performance marker in clinical assessments, as well in patient’s daily life. Specifically, Dr. Ilg will present innovative measures of dynamic balance while turning in people with spinocerebellar ataxia and their application in clinic and daily life. Dr. Alcock will highlight novel approaches to characterizing and validating turning in people with PD, in addition to detailing how discrete measures may be informative in specific clinical and research applications. Dr. Mc Ardle will present turning measures in individuals with dementia and its subtypes as well as discuss protocol generalizability for turning measures. Finally, Dr. Mancini will discuss the cortical correlates of turning in people with Parkinson’s disease and spinocerebellar ataxia. Compared to gait, turning research is in its infancy. Many challenges remain – as such, in the interactive discussion, we will discuss advantages and disadvantages of using turning performance measures in comparison to straight walking for the different diseases. Therefore, it is now a good time to make a summary of the biomechanical and cortical demands of turning in different neurological population, and discuss the best protocols to obtain sensitive measures to guide us in the future in preventing mobility disability in the community living.

Chair & Moderator:

Catherine P. Agathos, the Smith-Kettlewell Eye Research Institute

Presenters:

Catherine Agathos¹, Reza Saeedpour¹, Shirin Hassan², Sarah Creem-Regehr³, Colas Authié⁴

¹The Smith-Kettlewell Eye Research Institute, ²Indiana University, ³The University of Utah, ⁴Streetab

Visual impairment (VI) leads to reduced quality of life, depression, even increased mortality and is gaining attention as a growing health crisis as the number of individuals with irreversible vision loss rapidly increases. Individuals with VI often limit physical activities due to their poor vision and a fear of falling, which can lead to sedentary behavior and isolation, further impacting cognitive and motor functions. Mobility is crucial for autonomy and vision is important for guiding and controlling movement, yet VI’s impact on mobility has received relatively little attention compared to healthy vision. Although affected individuals use residual vision in daily life, the aspects of vision that are preserved and how they support day-to-day tasks are poorly characterized. Individuals with VI are highly heterogeneous: they may have various extents of central or peripheral visual field loss, occurring at different ages of onset and may be accompanied by comorbidities. Yet, studies have traditionally viewed VI as a monolith, grouping individuals together, and there is disagreement on the extent (or even existence) of mobility deficits, often attributed to other domains, e.g., aging. While in certain contexts, such grouping may be appropriate, others require a more nuanced approach. In addition, patient care seldom involves orientation and mobility training and spaces are rarely visually accessible. Moreover, the lack of established VI mobility protocols further hinders a consensus on individuals’ abilities and struggles in daily life. Mobility challenges also depend on environmental and task demands, e.g., the lighting and scale of the environment, negotiating obstacles or street-crossings, and additional pressures (such as time). Indeed, VI can present a cognitive burden as well, further complicating the issue. This symposium focuses on these challenges, highlighting individual and/or environmental variability across VI populations and tasks, and when such variability is relevant. We begin with basic science approaches examining gaze dynamics, spatio-temporal integration, and decision-making protocols to understand how VI individuals with different profiles plan their movements while negotiating obstacles and street-crossings. Next, we take a spatial cognition perspective to consider the interaction between visual deficits, environmental features and comorbidities of VI, from perceiving spatial relations to navigation, and the need/possibilities for visual accessibility. Finally, we discuss a novel mobility course, sensitive to the degree of VI, which can provide objective outcome measures. The work presented spans different innovative and cutting-edge methods including combined eye- and body- tracking, electroencephalography, simulated and real VI, and virtual reality. The symposium concentrates on understanding the needs of VI individuals, offering exciting perspectives for objective assessment, training and design of indoor and urban spaces.

Chair & Moderator:

Jeffrey P. Staab, MD, MS, Mayo Clinic, Rochester, MN USA

Presenters:

Jeffrey Staab¹, Mark Carpenter², Diego Kaski³

¹Mayo Clinic, ²University of British Columbia, ³University College London

Background: Studies of postural control have focused predominantly on vestibular, visual, and somatosensory inputs and deficits in peripheral and central neuro-vestibular structures that affect stance and gait. Alterations in postural functions have been thought to be consequences of structural deficits, rather than primary mechanisms of abnormal posture or sources of vestibular disorders. Psychological factors have been conceptualized as processes that influence posture rather than as elements that are integral to control of locomotion. Recent research on perception of motion suggests that this bottom up view of postural control is incomplete because it does not account for the top down effects of conscious awareness of movement or the key roles of threat assessment on locomotion. Clinical epidemiological data indicate that functional vestibular disorders such as persistent postural-perceptual dizziness (PPPD) are far more prevalent than structural neuro-vestibular disorders such as Meniere’s or Parkinson’s diseases. Aims: The goal of this symposium is to advance attendees’ awareness of psychophysiologic processes that are inherent to postural control and improve their understanding of alterations in functioning apart from deficits in structure that are common mechanisms of illness. Speakers will present a theoretical framework and experimental data on the dynamic top down effects of motion perception on postural reflex gains, motion detection thresholds, and activation of overlearned behaviors driven by predictions based on prior experiences (i.e., Bayesian logic) in healthy individuals and patients with structural and functional vestibular disorders. Relevance: A model that integrates structural, functional, and psychological processes is needed to advance research on posture and gait and improve care of patients with vestibular disorders.

Chair:

Caterina Rosano, University of Pittsburgh

Moderator:

Brad Manor, Harvard Medical School

Presenters:

Caterina Rosano¹, Caterina Rosano², Brad Manor³, On-Yee Amy Lo³, Nicolaas Bohnen⁴

¹University of Pittsburgh, ²School of Public Health, University of Pittsburgh, ³Harvard Medical School, ⁴University of Michigan

In older age, some persons move and function better than others, even for similar levels of locomotor risk factors. The source of such mobility resilience is currently unexplained. We propose the unique modulatory and adaptive capacity of central nervous and muscle skeletal systems may provide clues to understand the sources of such mobility resilience. We contend that the previously unrecognized relationship between the central nervous and skeletal muscle systems is one of the factors enabling adaptation/ compensation and thus resilience. This working model has the potential to generate discovery of new multi-systemic interventions to promote mobility resilience, not only for older adults, but also for other types of mobility impairments. There is strong biological plausibility supporting the cross-talk between the central nervous and skeletal muscle systems. Recent emerging evidence has offered insights into shared biological processes and molecular mediators of such cross-talk (e.g. mitochondrial function, myokines). However, evidence is primarily for animal models and selected patient populations with muscle degeneration. It is controversial how or whether such cross-talk occurs in older adults or persons with other conditions. This symposium builds on this very novel and emerging concept to increase the knowledge on brain-muscle cross-talk and underlying molecular mediators by drawing on basic and clinical studies. Our ultimate goal is to stimulate ideas to discover novel intervention targets. Attendees will learn the mechanisms and causes by which central nervous and muscle systems, individually and in combination, may drive mobility resilience. By drawing on basic and clinical studies, we will present recent epidemiological, experimental, and clinical trial evidence of multi-systemic energetic processes, dopaminergic neurotransmission, neuromodulation, and other non-pharmacological behavioral modifications. The level of complexity is designed to attract scholars from multiple fields and career seniority, from graduate student to senior faculty. We expect this symposium will promote discussions, networking, and exchanges of ideas among participants, with particular emphasis on involvement of junior investigators, women, minorities, and other underrepresented groups as contributors and discussants. Take away skills and learning objectives will include: a) Understand the determinants of muscle-brain cross-talk, its molecular mediators and energetic processes, and its clinical impact on mobility resilience; b) Formulate a summary of most recent intervention strategies targeting muscle-brain systems and how these effects may translate to mobility resilience; c) Identify knowledge gaps, barriers to progress, alternative strategies and utilize knowledge gained at this symposium to generate novel ideas and lines of inquiry; d) Learn about ongoing and existing studies with available biobanks and specimens of muscle, blood, brain databases.