Retraining the brain

Lorie Richards, Ph.D.

When a person experiences a stroke, damage happens quickly. In as little as four minutes, brain cells deprived of oxygen can become injured and die.

Rehabilitation researcher Lorie Richards, Ph.D., is studying ways to retrain remaining brain cells to take over for lost motor functions in the hands and arms of people with stroke. It’s a concept known as neuroplasticity and it refers to the nervous system’s ability to adapt after injury or disease.

“Once you have damage to your brain you’ve injured neurons and broken neural circuits that underlie all functional behavior. Right now we don’t have any way to replace those neurons and restore neural circuits so we’re trying to facilitate the existing neurons to form new connections and networks,” said Richards, an associate professor in the college’s department of occupational therapy and a research health scientist at the Brain Rehabilitation Research Center at the North Florida/South Georgia Veterans Health System.

One of the keys to re-building neural pathways is lots of practice, Richards said.

In Richards’ studies, patients with stroke practice everyday tasks like putting cans on cupboard shelves, washing dishes, folding laundry or playing games with their affected arm. Using an approach called Constraint Induced Movement Therapy, the research participants wear a hand mitt on the side of the body not affected by the stroke, forcing them to use the weakened arm. UF’s Kathye Light, Ph.D., of the department of physical therapy was one of the researchers who conducted the first large, multi-site randomized clinical trial of CIMT.

Rehabilitation researchers are still trying to pinpoint the most effective strategies for improving outcomes in this therapy, Richards said.

“We know the therapy needs to be intense and we know there needs to be lots of repetitions, but that’s about it at this point in time,” she said.

To help answer those questions, Richards has conducted a study in which participants hear auditory rhythm cues, in this case a metronome, while they practice the tasks. In another study she will evaluate whether adding a strength training exercise program to the therapy will result in better outcomes.

She was recently part of a research team that completed the first national rehabilitation multi-site clinical trial funded by the Veterans Administration. The researchers tested robotic devices fitted for the shoulder, arm and hand to help guide the movements of patients with stroke as they manipulate a computer mouse. She is currently working with Justin Sanchez, Ph.D., of the University of Miami and Jose Principe, Ph.D., of UF’s College of Engineering to develop a robot that takes the technology a step further by incorporating a brain-machine interface and virtual reality.

Richards is a co-investigator on a study led by Stephen Nadeau, M.D., chief of neurology at the Malcom Randall Veterans Affairs Medical Center and a professor of neurology in the College of Medicine, that will look at the effect of combining Constraint Induced Movement Therapy with drug therapies.

“We’ve already shown that we can make a difference with behavioral interventions,” she said. “What we need now is ways to make the brain more receptive to that behavioral input and more ready to change, adapt itself and reorganize.”