Research at PTRS

Investigator: Mark Rogers, PhD, PT, FAPTA SOM Faculty Profile GPILS Faculty Profile

 

Human Balance and Movement Control Laboratory

We are interested in the motor control mechanisms by which humans normally position and move their body segments and remain upright during everyday functional actions, and the changes that impair these functions and lead to disabilities with advancing age and neurological conditions such as Parkinson’s disease and chronic stroke. Our studies involve an integrative approach focused on understanding the interactions of neural, biomechanical, and behavioral systems contributing to balance and movement control. A particular focus is on how postural movements of the limbs such as protective stepping are controlled to stabilize posture and balance and on how such processes may be changed with age and pathology. Ultimately, these studies are directed at developing clinical rehabilitation approaches for evaluating and enhancing balance and movement performance.

Grant Support

Source: NIH R21HD055386
Title: Posture Assisted Locomotion Training in Persons with Parkinson’s Disease
Principal Investigator: Mark W. Rogers
Period: 2007-2009

Source: NIH P30 AG028747 (PI Andrew Goldberg) University of Maryland Claude D. Pepper Older Americans Independence Center, Pilot Project
Title: Hip Muscle Composition: Relationships with Neuromechanical Performance, Lateral Stability, and Risk of Falls in Older Adults
Prinicpal Investigator: Mark W. Rogers
Period: 2008-2009

Projects

• Lateral Stability and Falls in Older People
   
  Falls and their consequences are among the major problems in the medical care of older individuals. Ineffective balance recovery movements such as stepping are a major contributor to falls in the elderly. Yet, the causes of impaired balance leading to falls are uncertain. The purpose of this research is to examine the neuromechanical mechanisms contributing to impaired balance control and falls in older people. A novel robotic “people-puller” causes loss of balance to induce protective stepping in the laboratory where we use 3-D motion analysis and recordings of ground reaction forces and muscle activation patterns to study balance responses of older adults at risk for falls.
   
  
   
  Using experimental, modeling, and interventional approaches this project seeks to 1) understand the causes of why older people have most difficulty keeping their balance during falls to the side; and to 2) develop interventions to improve balance and prevent falls.


• Posture and Locomotion Interactions in People with Parkinson’s disease
   
  People with Parkinson’s disease (PD) frequently experience difficulties with performing whole body movements such as initiating and executing walking, turning, and rising from a chair. These problems are associated with falls and lead to disabilities. The purpose of these studies is to assess the feasibility of a novel therapeutic approach involving posture assisted locomotion (PAL) training to enhance step initiation and gait performance and reduce the incidence of /start hesitation’ and freezing of gait in individuals with PD. A custom designed “dropping” device is used to manipulate limb loading and assist patients with developing the postural forces needed to propel the body forward and sideways in order to begin walking.
  It is proposed that the repeated use of this technique to influence limb load proprioception will retrain the walking system to minimize delays in initiating walking and overcome freezing of gait episodes. Three-dimensional body movements, muscle activity patterns, and balance forces are studied to understand the neuromuscular and mechanical causes of FOG and their improvements due to PAL training.
• Preparation and Planning of Movement Initiation in Aging and Parkinson’s Disease
   
  Slowing of movement is a common accompaniment of human aging that limits motor function and represents a major risk factor for falls. These problems are exacerbated in people with Parkinson's disease who classically display marked delays in starting (akinesia) and executing (bradykinesia) movements.
   
  We are investigating the mechanisms by which the brain plans, prepares and then initiates and executes voluntary actions. We are using a variety of measurement techniques (acoustic and tactile startle stimulation, transcranial magnetic stimulation, and high resolution EEG) and movement paradigms to examine the roles of subcortical and cortical mechanisms in motor preparation and timing. Improved understanding of the mechanisms contributing to movement initiation is being translated into novel therapeutic interventions for the elderly and PD patients.

 

Collaborations

Uinversity of Maryland School of Medicine
Larry W. Forrester, PhD
Andrew Goldberg, MD
Richard Macko, MD
Sandy McCombe Waller, PhD, PT, NCS
Michelle G. Prettyman, PT, MS, DPT
Alice Ryan, PhD
Lisa Shulman, MD
Cristian Zampieri-Gallagheh, PhD, PT

Northwestern University
Marjorie J. Hilliard, MS, PT
Colum MacKinnon, PhD
Katherine Martinez, MA, PT
Tanya Simuni, MD
Yunhui Zhang, MS

Prince of Wales Medical Research Institute, Sydney, Australia
Richard C. Fitzpatrick, PhD, MD & Stephen R. Lord, PhD

University of Minnesota
Carl G. Kukulka, PhD, PT

University of Toulon, France
Marie-Laure Mille, PhD

University of Illinois Chicago/Rehabilitation Institute of Chicago
James L. Patton, PhD

Lab Personnel

Brett Sealine, MS, Research Coordinator/Lab Manager

Recent Publications

• Rogers MW, Hedman LD, Johnson ME, Martinez KM, Mille M-L. Triggering of protective stepping for the control of human balance: age and contextual dependence. Cog Brain Res, 2003;16:192-8.
• Rogers MW, Johnson ME, Martinez KM, Mille M-L, Hedman LD. Step training improves the speed of voluntary step initiation in aging. J Gerontol Med Sci 2003; 58: M46-51.
• Mille ML, Rogers MW, Martinez K, Hedman LD, Johnson ME, Lord SR, Fitzpatrick RC. Thresholds for inducing protective stepping responses to external perturbations of human standing. J Neurophysiol 2003; 90:666-74.
• Rogers M.W. & Mille, M-L. Lateral stability and falls in older people. Exer Sport Sci Rev 2003; 31: 182-187.
• Johnson M.E., Mille M-L., Martinez K.M., Crombie G., Rogers M.W. Age-Related Changes in Hip Abductor and Adductor Muscle Strength. Arch Phys Med Rehabil, 2004; 85: 593-597.
• Li S, Kukulka CG, Rogers MW, Brunt D, Bishop M. Sural nerve evoked responses in human hip and ankle muscles while standing. Neurosci Lett. 2004; 364:59-62.
• Simuni, T, Martinez, K.M., Rogers, M.W. Physical and Occupational Therapy in Parkinson Disease. In: Pahwa R, Lyons, KE, Koller, WC, eds. Therapy of Parkinson's Disease, 3rd Edition, New York, NY: Marcel Dekker, Inc., 2004; pp 481-490.
• Chung SG, van Rey EM., Bai Z, Rogers MW, Roth EJ, Zhang L-Q. Aging-related neuromuscular changes characterized by tendon reflex system properties. Arch Phys Med Rehabil. 2005;86:318-27.
• Mille M-L., Johnson ME, Martinez K.M., Rogers M.W. Age dependent differences in lateral balance recovery through protective stepping. J Clin Biomech 2005; 20:607-616.
• Edwards BJ, Langman CB, Martinez K Johnson M, Mille M-L, Rogers MW. Women with wrist fractures are at increased risk for future fractures because of both skeletal and non-skeletal risk factors. Age and Ageing 2006; 35:438-41. Epub 2006 May 11.
• Patton JL, Hilliard MJ, Martinez K, Mille ML, Rogers MW. A simple model of stability limits applied to sidestepping in young, elderly and elderly fallers. Conf Proc IEEE Eng Med Biol Soc. 2006;1:3305-8.
• Mille M-L, Johnson-Hilliard ME, Martinez K., Simuni T, Rogers MW. Acute effects of a lateral postural assist on voluntary step initiation in patients with Parkinson’s disease. Mov Disord. 2007; 22:20-7.
• St. George R, Fitzpatrick RC, Rogers MW, Lord SR. Choice stepping response and transfer times: effects of age, fall risk and secondary tasks. J Gerontol A Biol Sci Med Sci. 2007; 62:537- 42.
• MacKinnon CD, Bissig, D, Chuisano J, Miller E, Rudnick L,; Yager C, Zhang Y,; Mille, M-L, Rogers MW. Preparation of Anticipatory Postural Adjustments Prior to Stepping. J Neurophysiol, 2007; 97:4368-79. Epub 2007 Apr 25.
• Butler AA, Lord SR, Rogers MW, Fitzpatrick RC. Muscle weakness impairs the proprioceptive control of human standing. Brain Res, 2008 Apr 16. [Epub ahead of print].
• Johnson Hilliard M, Martinez KM, Janssen I, Edwards B, Mille M-L, Zhang Y, Rogers MW. Lateral BalanceFactors Predict Future Falls in Community Living Older Adults. Arch Phys Med Rehabil. 2008;89:1708-13.
• Rogers MW, Martinez KM. Recovery and Rehabilitation of Standing Balance After Stroke. InStein J, Harvey R, Macko R, Winstein C, Zorowitz R, eds. Stroke Recovery and Rehabilitation. New York, NY: Demos Medical Publishing, in press.