Probing the mysteries of movement

For most of us, turning a door handle, grabbing a coffee mug or flipping a light switch are everyday acts we do without thinking. For York University science Professor Denise Henriques, these seemingly simple acts of hand-eye coordination are a source of great fascination, because there’s much more happening in our brains at these moments than we realize.

Right: Denise Henriques

“Most of the brain is devoted to figuring out where things are in space, how fast they’re approaching us and how to move to them,” says Henriques, a professor in York’s School of Kinesiology & Health Science. “By understanding how the brain controls movement, we can understand one of the fundamental functions of the brain.”

Figuring out how the brain uses sensory data to control the body’s movements is the central theme of Henriques’ research, and it’s led to some pioneering – and award-winning – results that may one day change the way we treat neurological disorders.

Working out of a state-of-the-art laboratory at York’s Centre for Vision Research, Henriques and a team of seven graduate and undergraduate trainees simulate sensorimotor systems on computers to identify issues and to reveal the implications of different theories. Currently, they are testing competing theories through nine different behavioural experiments that involve presenting human subjects with multisensory stimuli and recording their eye, head and limb movements.

Their goal is to investigate three main areas of sensorimotor function: how the brain represents and processes spatial information at various stages of motor control; how it coordinates multiple senses to steer multiple body parts; and, how it interprets sensory feedback to drive motor learning.

Generating much interest among her peers as well as government grant organizations is Henriques’ finding of how the brain uses information, stored in spatial memory, to guide movement. “Humans tend to be visually dominant, but we’ve found that vision doesn’t have a lasting effect on how well we perceive our hand movement,” says Henriques.

Left: Henriques in her lab at York University

Plumbing the depths of the human brain is a long-time passion for Henriques, 34, one that first found an outlet in the form of psychology studies at York. She completed her PhD in 2002, but along the way, tried something new and studied law, simultaneously earning a degree from Osgoode Hall Law School in 2001.

The law, however, proved no match for the complexities of the brain and its treasure trove of still untold secrets.

“We are so versatile, and compared to any other animal we can do so many things, and it’s purely because of our larger brains,” says Henriques, who, after completing post-doctoral studies at the University of Western Ontario and the University of Minnesota, returned to York in 2004. “I want to understand how the brain works because it can help us solve all sorts of problems.”

Indeed, Henriques’ research may one day play a role in changing the way we assess, treat and rehabilitate those with common and debilitating neurological disorders caused by strokes, tumours, injuries and degenerative disease.

“By increasing our basic knowledge of the brain and how it processes repeat movements, we may be able to understand how to rehabilitate people with damage to certain areas of the brain,” she says.

Greater knowledge about sensorimotor functions may also advance the field of robotics, for example in the area of remote surgery, and enhance the way physical education is taught to children and athletes.

Henriques isn’t the only one who thinks she may be onto something. The federal and provincial governments, the Banting Research Foundation and York University have all recognized the potential of her work and granted her almost $800,000 in funding over the last three years. Last year, she was awarded a $15,000 Polanyi Prize by the government of Ontario in recognition of her progressive research in the area of physiology/medicine.

As far as Henriques has come, however, she knows there’s still much work to do to tease precious answers out of the recesses of the human brain. “We know that our brains are very adaptable and sophisticated, but there’s still a lot to learn about how the brain works,” she says. “This research provides one more clue.”