Muscle synergy analysis during exoskeleton assisted walking


May 13, 2022 1:00 PM — 2:00 PM remote via Zoom


CDM 222 and online


Taimoor Afzal, Worcester Polytechnic Institute, USA


According to a recent UN report, about 1 in 6 people suffer from neurological disorders. That’s nearly 1 billion of the world’s population. Persons with neurological disorders lose the ability to control their arms and legs in a meaningful way. In some cases, the disorders lead to complete paralysis. This makes human movement control an extremely important area of research. It is hypothesized that the central nervous system activates a group of muscles to contribute to a particular movement thus reducing the dimensionality of muscle control. This concept is known as muscle synergies. However, this control is disrupted after an injury to the brain or spinal cord. The study of muscle synergies has great implications when studying movement control during disease states, such as stroke, multiple sclerosis, and spinal cord injury. In this talk, I will highlight the use of a mathematical model to extract muscle synergies from the electrical activity recorded from different muscles during walking. We will then examine how this model can be used to study movement patterns during walking after an injury. The application of this model during walking with and without an exoskeleton (robots that assist people to walk) will be demonstrated.


Dr. Taimoor Afzal is an Assistant teaching professor in the Department of Biomedical Engineering at Worcester Polytechnic Institute. His research interests lie in human movement control, machine learning, and neural engineering. During his PhD, his research focused on developing a machine learning algorithm based on the notion of muscle synergies for classification of different walking modes. Later in his career, he worked at the University of Texas Health Science Center at Houston where he examined the feasibility of exoskeletons for assisted walking in patients with neurological disorders. Most recently, he was working as a postdoctoral researcher at Northwestern University, where he examined the mechanisms of muscle weakness in stroke and the bilateral effects of stroke on motoneuron excitability.