A recent PhD graduate from UNB is the New Brunswick Health Research Foundation’s Rising Star for May for his research on improving how amputees adapt to using their new prostheses.
Ahmed Shehata just started his post-doctoral fellowship at the University of Alberta. Over the past three years, he’s been researching what’s called “internal models” and how they can be better improved to help amputees with their myoelectric prostheses.
Myoelectric prostheses mimic human anatomy and motion and are one of the closest alternatives to an anatomical hand or arm. Internal models are formed in our minds and they contain information about the environment surrounding us, our bodies (size and weight), and sensory feedback (vision, touch, et cetera).
“For example, if we’re learning how to play basketball, we use vision, how we see the basketball,” says Shehata. “We use the size and the weight of the ball by touching and carrying it and then throw the ball into the hoop. We use all this information to build what we call an ‘internal model’ in our minds for playing basketball ”
His recently published paper, “Evaluating Internal Model Strength and Performance of Myoelectric Prosthesis Control Strategies,” looks at how strong these internal models are. Could they be modified easily? Is this model the best model a person can develop for a specific task? They then apply this analysis to controlling a myoelectric device.
“For an amputee, it is often very challenging for them learn how to control myoelectric devices. It requires them more time and practice to learn how to use a myoelectric prosthesis,” says Shehata.
“In this paper we’re applying a framework of assessing the internal model, which reflects the human understanding, to the field of myoelectric prosthesis control. We were able to assess the effect of using different myoelectric control strategies to control the prosthesis on the internal model.”
For example, they looked at two specific myoelectric control strategies – one that provided the person with lots of feedback, and one that provided the person with just about the right feedback that is needed to perform a specific task. They discovered that the more feedback you provide, the more effective the internal models are.
“We found out that the controller that provided the person with more feedback about the state of the controllers, about the state of their muscles, about the state of the activation of the muscles itself in their arms, allowed them to understand better the myoelectric controller they are using by developing stronger internal models,” says Shehata.
All this research may sound very “sciency,” but the reason Shehata wanted to pursue this field of study is a very human one.
“I want to feel that I’ve contributed enough not only to science but to improving human lives. Losing a limb is a very huge deal, specifically, if we’re talking about hands or arms,” he says. “We use our hands every day to craft and manipulate objects. It’s a product of many years of training, including our childhood. It’s a sophisticated blend of both how we control our hands in a free-flowing manner without too much thinking and how we use feedback (like touch) to adjust our control.”
So Shehata wants to help make the experience of learning how to use a limb all over again through a prosthesis more comfortable and effective. Not only that, he wants to make living with a prosthesis feel more natural.
“It’s not only about controlling the device that got me into this, but also I wanted to restore the sensation itself. The sensation from the prosthetic device that they are using to the person,” says Shehata. “Restoring the sensation is something important. It’s like communicating back from the machine, which is the prosthetic device, to the person. Eventually, the person will feel that ‘This is not only a tool anymore, it’s a part of my body’.”
Shehata says New Brunswick has been an ideal place to do research. He says by working at the Institute of Biomedical Engineering at UNB, he was given opportunities he may not have gotten anywhere else.
“It’s not only an educational and research institute, it also houses the Atlantic Clinic for Upper-limb Prosthetics. So, I got the exposure to not only the virtual environment type of testing, but also the experience of seeing actual amputees fitted with prosthetic devices,” he says. “This actually helped me a lot in visualizing what I should be targeting in the future.”
Doing his research in the province also gave him access to funding, with the research for his paper was partly funded by the New Brunswick Health Research Foundation. Shehata says that kind of support is crucial to young researchers to be successful.
“Access to this kind of funding is important for young researchers,” he says. “It allows researchers to focus more on doing their research and communicating their research to the world by attending and presenting at conferences.”
Once a month, from January to October, in the lead-up to the 6th Gala of Excellence in health research in November, the NBHRF will present $250 to the monthly Rising Star winners in each of the award categories (Master’s, Doctoral, Post-doctoral & Research Professional). All monthly winners will be showcased at the 6th Gala of Excellence in November 2018 and an Annual Winner will be announced.