Understanding the Role of Sustained Attention and Effort in Arm Non-use in Stroke

Female physical therapist working with an older patient to build arm strength.

Jane suffered a stroke that impacts the sensation, strength, and dexterity of one of her arms.  She worked hard in inpatient neurorehabilitation, and assessments showed that her capacity to use the arm greatly improved.  When she returned home, however, her spouse noticed that she continues not to use the affected arm much in daily activities, preferring to rely on the other arm or to ask others for help. In fact, over time her use of the affected arm actually seemed to be decreasing.

One of the most challenging aspects of neurorehabilitation of stroke is that many individuals with adequate sensory-motor recovery and capacity to use their impaired arm do not actually do so.

Instead, there is a maladaptive pattern of over-use of the relatively intact arm, resulting in a vicious cycle in which the affected arm loses the gains that resulted from neurorehabilitation.  Can we identify the factors that make people likely to show this pattern of non-use?

One obvious factor might be the ability level of the affected arm:  people clearly favor their less-impaired arm if the impaired arm is particularly limited.  Working with a team from University of Southern California (USC), the MRRI Cognition and Action Lab headed by MRRI Associate Director Laurel Buxbaum, PsyD, performed a study showing that even when the severity of arm impairment is taken into account, a second factor—sustained attention – plays an important role in determining whether individuals are likely to use that arm. 

The researchers suggest that this pattern fits with the importance of sustained attention and ability to expend effort in a variety of cognitive and motor tasks, and with the idea that arm use occurs on the basis of an implicit cost-benefit analysis.  In individuals who have suffered a stroke, the reduced sensory-motor capacity of the impaired arm requires extra sustained attention and effort to overcome.  That is, movement comes at a greater “cost”. At the same time, however, the stroke diminishes the ability to deploy attention and effort. “To shift the cost-benefit relationship”, says Dr. Buxbaum, “we need to increase the degree to which use of the impaired arm is associated with reward”.

Neurorehabilitation programs can shift the cost-benefit relationship to favor arm use in a variety of ways.  Some direct ways including “gamifying” arm use via virtual reality and other motivating games, or allowing accumulation of points or rewards for arm use.  In addition, therapists can use goal-setting, peer support groups, family involvement with goals, and frequent check-ins to boost the reward associated with using the impaired limb.  In fact, therapies that have been associated with such benefits (sometimes termed “transfer packages”) have generally been more successful than those that do not.

Dr. Buxbaum and her colleagues from USC recently published a peer-reviewed study on the factors determining non-use in the journal Neurorehabilitation and Neural Repair.  Along with MRRI Institute Scientist Shailesh Kantak, PhD, the researchers are in the process of developing a funding proposal for follow-up research.

Moving to Complex Skills More Quickly in Stroke Rehab


During stroke rehabilitation, therapists and physicians traditionally start patients with simple skills and then slowly build to more complex activities. The idea is to begin slowly and move to more demanding activities as the patient seems ready. Is there a more effective approach?

In this video, Shailesh Kantak, PhD, shares his research suggesting that patients could move to complex activities more quickly. Continue Reading

MRRI advances neurorehabilitation with innovative technologies

The emergence of new technologies has added fascinating new dimensions to MRRI’s research in translational neurorehabilitation. Using virtual reality in the treatment of phantom limb pain, noninvasive brain stimulation to improve stroke patients’ motor deficits, and iPhone apps to track concussion symptoms after a sports injury are some of the ways in which MRRI researchers are using tech in their work. Here’s an overview of the ways in which researchers Laurel Buxbaum, Amanda Rabinowitz, and Shailesh Kantak are using tech to push neurorehabilitation research into the future. Continue Reading

MRRI Scientist Studies How the Brain Processes Language to Learn about Stroke

Edward Wlotko, PhD, has been studying how the brain processes language since he was an undergraduate at the University of Pittsburgh. And his interest in language comprehension—particularly how the two hemispheres interact to make that happen—deepened in graduate school, at the University of Illinois at Urbana-Champaign. There, he devoted his dissertation work to understanding the differences in how language is processed by each hemisphere of the brain, the two sides working separately and in tandem.

Edward Wlotko, PhD

Before coming to Moss Rehabilitation Research Institute, Dr. Wlotko completed two post-docs, one at the Beckman Institute for Advanced Science and Technology at the University of Illinois, the other at Tufts University.

“In my first post-doc,” says Wlotko, “I studied language in the aging brain. At Tufts, I used neuroimaging to study college-aged adults’ language comprehension. So when I got to MRRI I wanted to combine and extend these areas of research from my past work.”

Now, as director of the MRRI Cognitive Neurophysiology and Neuropsychology Lab, Wlotko is trying to further understand how language works in healthy brains to ultimately help problems with language caused by stroke. For example, mapping what facets of language comprehension and production are governed by the two sides of the brain will provide clues to the kind of language or communication difficulties someone might experience after a left vs a right hemisphere stroke. Wlotko believes it is important to approach this question from both angles: Learning about the healthy brain helps researchers understand what happens in the damaged brain—and learning about what’s going on during stroke helps researchers understand more about the healthy brain. Continue Reading

Focusing on Visual Perception to Improve Motor Performance After Stroke

Mirror Therapy

Steven Jax, PhD, has spent most of his career at Moss Rehabilitation Research Institute (MRRI), and doesn’t have plans to leave any time soon. Dr. Jax came to MRRI from Penn State, where he did his doctorate work in basic sensorimotor processing. He began his tenure at MRRI as a post-doc in the lab of Laurel J. Buxbaum, PysD. There, he began his research on rehabilitation in stroke patients, which he’s expanded over the years as director of the Perceptual-Motor Control Laboratory. Continue Reading