Living with Parkinson's
In the Balance: Kristen Clark, a senior in nutrition science, puts a University Place resident through the paces of the Biodex Balance System, which uses visual feedback to mimic the everyday activities where people might be in danger of falling. (Photo by Andrew Hancock)
While these HHS researchers search for Parkinson's causes, other faculty research is leading to improvement in the quality of life for those stricken with the disease.
Jessica Huber, associate professor of speech, language, and hearing sciences, teamed with Jeffrey Haddad, assistant professor of health and kinesiology, on a study that looked at the ability of patients with Parkinson's disease to balance and talk.
"People with Parkinson's are more apt to fall because walking, standing and talking are all very cognitively demanding," Haddad says. Neural circuits between the basal ganglia and the frontal lobe are responsible for the ability to do more than one thing at a time. These areas are impaired in patients with Parkinson's disease, and they often have difficulty managing multiple tasks simultaneously.
To examine this problem, Haddad and Huber had individuals with Parkinson's disease and typical older adults stand on a metal force plate to measure balance. While the subject was standing on the plate, a computer monitor displayed pictures and commands to say certain sentences that varied in language complexity. Haddad says, "We examined how their balance changed when they had to generate more complex speech or memorize things while standing and talking."
This earlier investigation led to a study collaboration with Shirley Rietdyk, associate professor of health and kinesiology. Her research focuses on the interaction of neural and mechanical systems in mobility, posture and balance.
Rietdyk, Haddad and students conducted a study at University Place, a continuing care retirement community, using a new balance device call the Biodex Balance System. It is similar to the Wii Fit game but the base is unstable, like a wobble board with visual feedback.
"If you want to test someone's balance, you don't just have them stand still," Rietdyk says. "You have to challenge their balance system because people are more likely to fall when they're moving during everyday activities such as walking, stepping up onto a curb or reaching forward to put something in a cupboard. The risk of instability increases further if they are completing another task at the same time, such as talking to their spouse while carrying a tray of food."
They train people with balance and mobility issues in a difficult task to improve stability in their everyday lives.
Haddad and Rietdyk did a six-week intervention with older adults without Parkinson's at University Place three times a week for 20 minutes at a time. They assessed the group in the Biomechanics Lab and the Motor Development Lab and found that the benefits of training transferred to Haddad's manual precision task and to Rietdyk's mobility task requiring subjects to walk and step over obstacles.
"Even though our training did not include walking or manual precision tasks, the intervention improved their mobility and their balance while reaching forward," Rietdyk says.
Better Walking and Talking
A new research investigation will study treadmill and Biodex training to improve mobility in patients with Parkinson's disease and typical older adults.
Though it may sound like an impossible task for those with mobility issues, Haddad says treadmill training helps patients overcome halting or freezing of gait by forcing them to walk because the belt is moving.
Subjects are harnessed for safety. "The treadmill belt pulls the foot backward," Rietdyk says, "providing an external cue to push them beyond their level of comfort in walking."
Haddad, Rietdyk and Huber will compare Biodex training to treadmill training to see which is more beneficial and if gains translate to improvement in quality of life.
Rietdyk says one of the most satisfying outcomes of the research has been the involvement of undergraduates in the training. "It was rewarding to see relationships develop between the students and the residents at University Place. The students became much more invested in the research than I've seen in other projects."
In addition to mobility studies, Huber and colleagues in the Purdue Research Park have created a wearable device, the SpeechVive, improving both loudness and clarity of speech in patients with Parkinson's disease in real-world conversations, not just in a speech therapist's office.
"People with Parkinson's disease commonly have voice and speech problems," Huber says. Because of these difficulties with communication, patients often feel invisible or ignored.
The SpeechVive plays noise, called multitalker babble, which resembles the noisy chatter of a restaurant full of patrons in one of the patient's ears while he/she is speaking. The noise elicits a reflex called the Lombard effect and the patients talk more loudly and clearly.