January 20, 2010

Behind the Mask of Parkinson’s

Researchers explore the communications hurdles faced by those with the disease and how they can be overcome

By Robert Bochnak

The man in the video sits alone, speaking about a wedding he recently attended. On the surface, there’s nothing unusual about the conversation, but as the tape goes on, a curious flatness in his voice and manner are evident. Linda Tickle-Degnen, professor and chair of occupational therapy in the Graduate School of Arts and Sciences, lets the video run for a few minutes before she begins making observations.

People with Parkinson’s disease can exhibit “facial masking,” a symptom in which facial muscles become immobilized, leaving them with blank expressions. Illustration: James Steinberg

She starts with the man’s lower body, noting that he hasn’t moved or otherwise repositioned himself since the interview began. Next, she calls attention to his left hand, which has been trembling slightly. She ends with his face, but no explanation is necessary: he’s remained almost expressionless.

To the untrained eye, the man appears disinterested, even bored. But to Tickle-Degnen, it’s clear that the subject, a Parkinson’s disease patient, is exhibiting “facial masking,” a symptom in which facial muscles become immobilized, leaving patients with blank expressions.

“The face is the primary way we communicate with other people,” says Tickle-Degnen, who has been researching nonverbal and verbal communication among people with Parkinson’s and other diseases for the past 20 years. “We tend to believe the actions of a person more than their words. So a person with Parkinson’s disease may be saying that they are really enjoying life, but may not be believed.”

Work being done at the Tufts Health Quality of Life Lab, which Tickle-Degnen directs, could be instrumental in helping people with Parkinson’s express themselves better and be understood more clearly. Right now, the research is focused on improving communication in an area where many such patients have important relationships—the health-care system.

“Practitioner-patient interactions are social relationships,” says Tickle-Degnen. “If a neurologist, speech therapist or occupational therapist gets the feeling that the person they’re working with is disinterested or depressed, then this relationship can be affected.” Tickle-Degnen notes that even experts sometimes fail to ask patients with Parkinson’s about their feelings, because facial masking hides depression, deception, hostility and apathy.

“If there were a way that we could train practitioners to better detect how positive or negative a person was feeling, we could help strengthen these relationships,” Tickle-Degnen says.

Anatomy of a Smile

“I see it as a challenge, to get out there and help people understand why this work is so important for people with Parkinson’s,” says Linda Tickle-Degnen. Photo: Alonso Nichols

There are at least 43 muscles in the human face. Working in concert with other parts of the body, these muscles help people to smile, frown, grimace and express subtle feelings. The key to these movements can be found in the neurotransmitter dopamine, which helps regulate how people produce facial expressions, as well as walk, run, perform hand gestures and carry out other movements in a coordinated way. But when dopamine-producing cells in the brain are damaged, the result can be an inability to control motor functions. This loss of motor control is a key feature of Parkinson’s disease, which affects some 1.5 million Americans and is the second most common neurodegenerative disease, after Alzheimer’s.

Parkinson’s symptoms include tremors, limb stiffness and difficulty moving and maintaining balance. If you add the vocal challenges of Parkinson’s to the mix—some, like the man in Professor Tickle-Degnen’s video, have difficulty modulating the tone of their voices—it would seem that the obstacles to effective communication with the outside world are insurmountable. But Tickle-Degnen is optimistic.

While emotions may not be visible on the faces of many people with Parkinson’s, it is possible to find out what they are feeling if you focus on what she calls “reliable cues,” the ones that don’t change even with facial paralysis.

Tickle-Degnen and her team of researchers have conducted and videotaped 500 interviews with Parkinson’s patients as part of their research. A typical interview consists of a series of positive (“what do you enjoy doing?”) and negative (“describe a frustrating event that occurred last week”) response questions. Subjects are then rated using a coding system Tickle-Degnen developed, called the Interpersonal Communication Rating Protocol. Using it, coders look at, among other things, the frequency with which subjects express nonverbal cues.

“For all the interviews, we analyze facial behavior, body movement and voice, and we also do text analysis,” says Tickle-Degnen. “I ask them about their feelings: if they are happy, unhappy and so on. We’re looking for particular cues.”

Beyond feeling and mood, personality is also expressed through the body. “People who are very sociable and extroverted tend to use large motions with their hands and tend to be very facially expressive, meaning that their faces are showing a lot of motion,” says Tickle-Degnen. Yes, motion, she says: their faces are moving. “And when they tend to be more introverted or shy, they tend to move less in their whole body. Their body is a little bit more quiet, and their facial expression is quieter.”

Training to Read Parkinson’s Patients

Although the research is still being collated, some critical findings have emerged. One is that when patients are asked positive questions, their facial masking is less intense, says Tickle-Degnen.

“This is really important for people who work with Parkinson’s patients, since many tend to do what is called a ‘problem-oriented interview.’ They ask, ‘What problems are you here to talk to me about today?’ Typically, nobody asks people with Parkinson’s about positive things, because there’s not much positive emotion on their faces,” she says.

The next step for the researchers is to train health-care practitioners how to interpret their patients’ nonverbal cues and help them focus more on what the patients are actually saying—a practice that goes against the way people intuitively read one another, which is visual.

“Perceptions of sociability are biased, based on the stiffness and rigidity that can result from Parkinson’s,” says Heather Gray, a postdoctoral fellow in the Health Quality of Life Lab, whose research involves training Tufts graduate and undergraduate students to recognize certain cues in people with Parkinson’s.

Looking for Cues

Once the coding process for the interviews is complete, short clips of them are shown to Boston-area doctors and therapists, whose own responses are then studied and analyzed.

“We ask the practitioners to tell us how happy, depressed or cognitively intact they think the person is. We also ask them to tell us how sociable they think the person is and what mentally challenging activities he or she might be interested in,” says Tickle-Degnen, whose research has been supported by the NIH’s National Institute of Neurological Disorders and Stroke and National Institute on Aging.

“These are not judgments about how much smiling the person is doing, but more social level or diagnostic judgments,” she says. This type of information is critical, since judgments like these play key roles in treatment decisions.

Although Tickle-Degnen’s research takes place primarily at the Tufts lab and in Boston-area hospitals, the scale of the study is global. She is also studying how practitioners from Taiwan perceive patients with Parkinson’s, since cultural norms affect people’s perception of facial masking. Tickle-Degnen says their findings show practitioners may “think they’re being objective in their diagnoses, but that they are being driven by cultural norms in determining depression or dementia or lack of it.”

She’s also doing research that will help people with Parkinson’s deal with their condition. In collaboration with neuron-rehabilitation and movement disorder clinics at Boston University, she has conducted a randomized control trial that studied three groups of Parkinson’s patients: one that was given medication only and two that were given medication and different intensities of “self-management rehabilitation.” This included facial exercises that helped patients retain their facial expressivity to some extent.

“The primary thing we’ve measured so far is quality of life,” says Tickle-Degnen, who has advanced degrees in both occupational therapy and psychology. Those people who received rehabilitation reported that their quality of life was greater, in terms of their ability to communicate with others and not be misunderstood, and to move around the community to perform their daily life activities.

She believes the best step in shrinking the communication divide between practitioners and those with Parkinson’s is sharing what she and her researchers have discovered. But she concedes that getting the word out is just the beginning. She’s published widely and been quoted in national media outlets such as National Public Radio and the Boston Globe.

“It’s wonderful to have people read the articles we have published,” she says. “It’s another thing for people to actually use what we have found. I see it as a challenge, to get out there and help people understand why this work is so important for people with Parkinson’s.”

To learn more about the Health Quality of Life Lab and its Parkinson’s-related research, call 617-627-4667 or go to http://ase.tufts.edu/hql.

A longer version of this story appeared in the Summer 2009 Alma Matters magazine.

Robert Bochnak can be reached at robert.bochnak@tufts.edu.

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