Variable Visual Stimulus as a Novel Approach for Gait Rehabilitation (VISNA)

Deterioration in walking performance as a result of disease or simply as a result of aging is a serious threat to independence in older adults. In this project, the investigators propose an innovative visual stimulus, based on advanced mathematical and biological theories, with which older adults can walk in time to improve their walking. The investigators' goal is to apply this simple, cost-effective, and novel gait rehabilitation therapy across all populations who have difficulties walking, e.g. stroke patients, fallers or those who undergo joint replacement.

Study Overview

• Status: Terminated
• Conditions: Gait Disorders, Neurologic
• Intervention / Treatment: Behavioral: Fractal visual cueing; Behavioral: Periodic visual cueing; Behavioral: Random visual cueing

Detailed Description

Walking synchronized to a visual stimulus is commonly used for gait rehabilitation, and has been shown to alter gait parameters such as stride length and stride time in a variety of patient populations. Typically, the patient is instructed to walk by stepping on lines or other markers placed on the ground presented in a fixed, invariant distance with each other. Whilst improvements in gait parameters have been observed in these experimental conditions, the investigators submit that a fundamentally different approach could lead to much greater benefits. The investigators' laboratory has successfully shown that walking to an invariant stimulus, with no variability, runs contrary to the natural stride-to-stride fluctuations (i.e., gait variability) that are known to exist in human gait. The investigators propose that the elimination of variability from gait, as is the case when walking with invariant external cueing, will not provide the movement abilities needed by individuals with reduced mobility to navigate the real world, unpredictable environments. In this project, the investigators propose an alternative approach to rehabilitation of gait disorders with respect to external cueing that takes the natural variability of healthy gait into account. The investigators have previously shown that young and older adults when walking to an invariant stimulus, display diminished natural stride-to-stride fluctuations. Preliminary data has also shown that the natural stride-to-stride fluctuations that exist in healthy gait are altered with aging, but can also be restored to levels similar to young adults when walking to a Variable Visual Stimulus. The investigators proposed solution is then to transform the standard invariant visual cueing paradigm by using a Variable Visual Stimulus that reflects the variable movement patterns found in healthy gait. This is because the presentation of our Stimulus will be variable, but it will not be random. There will be a pattern contained within the presentation of our Stimulus that is based upon the patterns found in healthy young adults. This project will investigate the long-term effects of viewing an invariant, a random and a variable visual stimulus on gait variability in older adults. Furthermore, the investigators will investigate the retention effects at 1- and 3-months of an 8-week program. The central hypothesis is that older adults who are at risk of falling will demonstrate greater improvements in gait variability and adaptive gait tasks when walking with a Variable Visual Stimulus that reflects the variable movement patterns found in healthy gait. The impact of this project will be transformational regarding gait rehabilitation for older adults who are at risk of falls. This simple, cost-effective method would be accessible to all gait rehabilitation clinics requiring only ubiquitously available glasses.

• Study Type: Interventional
• Enrollment (Actual): 1
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Nebraska
    • Omaha, Nebraska, United States, 68182
      • University of Nebraska at Omaha

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years to 90 years (Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Be able to provide informed consent.
• Be able to walk independently without an assistive device.
• Not suffer from neurological disease.
• Not suffer from any lower limb disabilities, injuries or disease.

Exclusion Criteria:

• If diagnosed with a pathology that directly affects the musculoskeletal system such as rheumatoid arthritis, neuropathy or myopathy, vertigo, joint replacement, diabetes, stroke or other vascular problems, scoliosis, uncorrected vision problems,major surgery in the last 6 months, or acute illness.
• Any neurologic conditions or lower limb disabilities or disease.
• History of seizures, migraines or headaches, or are visually impaired.
• Subjects unable to walk unassisted or unable to perform 10 minutes of continuous walking.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fractal visual cueing; This stimulus will consist of a visual moving bar displayed on a small monitor attached to a pair of glasses. The temporal structure of the movement will be fractal (i.e., pink noise). Participants will be asked to match their hell strikes of right foot with the top of the moving bar's path and their heel strikes of left foot to the bottom.	Behavioral: Fractal visual cueing; Walking to an external visual fractal (i.e., pink noise) stimulus.
Active Comparator: Periodic visual cueing; This stimulus will consist of a visual moving bar displayed on a small monitor attached to a pair of glasses. The temporal structure of the movement will be periodic (i.e., invariant). Participants will be asked to match their hell strikes of right foot with the top of the moving bar's path and their heel strikes of left foot to the bottom.	Behavioral: Periodic visual cueing; Walking to an external visual periodic (i.e., invariant) stimulus.
Sham Comparator: Random visual cueing; This stimulus will consist of a visual moving bar displayed on a small monitor attached to a pair of glasses. The temporal structure of the movement will be random (i.e., white noise). Participants will be asked to match their hell strikes of right foot with the top of the moving bar's path and their heel strikes of left foot to the bottom.	Behavioral: Random visual cueing; Walking to an external visual random (i.e., white noise) stimulus.
No Intervention: Control; Natural walking.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Stride length	Meters	Through study completion, an average of 1 year
Stride time	Seconds	Through study completion, an average of 1 year
Stride speed	Meters/seconds	Through study completion, an average of 1 year
Cortical hemodynamics	Micromoles	Through study completion, an average of 1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Joint angles	Radians	Through study completion, an average of 1 year
Peak torque of knee extensor muscles at 60º/s	Newton-meters	Through study completion, an average of 1 year

Collaborators and Investigators

• Sponsor: University of Nebraska
• Investigators: Principal Investigator: Luis M Silva, PhD, University of Nebraska

Publications and helpful links

General Publications

• Stergiou N, Decker LM. Human movement variability, nonlinear dynamics, and pathology: is there a connection? Hum Mov Sci. 2011 Oct;30(5):869-88. doi: 10.1016/j.humov.2011.06.002. Epub 2011 Jul 29.
• Brach JS, Wert D, VanSwearingen JM, Newman AB, Studenski SA. Use of stance time variability for predicting mobility disability in community-dwelling older persons: a prospective study. J Geriatr Phys Ther. 2012 Jul-Sep;35(3):112-7. doi: 10.1519/JPT.0b013e318243e5f9.
• Brach JS, Studenski S, Perera S, VanSwearingen JM, Newman AB. Stance time and step width variability have unique contributing impairments in older persons. Gait Posture. 2008 Apr;27(3):431-9. doi: 10.1016/j.gaitpost.2007.05.016. Epub 2007 Jul 13.
• Brach JS, Lowry K, Perera S, Hornyak V, Wert D, Studenski SA, VanSwearingen JM. Improving motor control in walking: a randomized clinical trial in older adults with subclinical walking difficulty. Arch Phys Med Rehabil. 2015 Mar;96(3):388-94. doi: 10.1016/j.apmr.2014.10.018. Epub 2014 Nov 10.

Helpful Links

• Kaipust JP, McGrath D, Mukherjee M, Stergiou N. Gait variability is altered in older adults when listening to auditory stimuli with differing temporal structures. Ann Biomed Eng. 2013;41(8):1595-1603. doi:10.1007/s10439-012-0654-9.

Study record dates

Study Major Dates

• Study Start (Actual): November 9, 2018
• Primary Completion (Actual): July 15, 2019
• Study Completion (Actual): July 15, 2019

Study Registration Dates

• First Submitted: November 7, 2018
• First Submitted That Met QC Criteria: November 8, 2018
• First Posted (Actual): November 9, 2018

Study Record Updates

• Last Update Posted (Actual): September 3, 2024
• Last Update Submitted That Met QC Criteria: August 29, 2024
• Last Verified: August 1, 2024

More Information

Terms related to this study

• Keywords: Rehabilitation; Gait; Brain; Variability; Visual; Fractals
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Gait Disorders, Neurologic
• Other Study ID Numbers: 0395-18-FB

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No