Jan 5, 2026
OT researcher earns pilot grant to uncover how the brain adapts movement
Project also explores why essential tremor may disrupt it
When Brooke Dexheimer, Ph.D., OTD, OTR/L, joined VCU Occupational Therapy, she built her research program around a deceptively simple question: How do we learn to move? Her newest grant – a $75,000 pilot award from the VCU Parkinson’s and Movement Disorders Center – takes that question deeper than ever before, quite literally.
Dexheimer is partnering with VCU biomedical engineer Dean Krusienski, Ph.D., and neurosurgeon Kathryn Holloway, M.D., on a first-of-its-kind study that brings occupational therapy into direct collaboration with neurosurgery and engineering. They are investigating how the brain’s electrical signals support “motor adaptation,” the split-second ability to tweak and correct movement as our environment changes — and to understand how this process breaks down in people with essential tremor, the most common neurological diagnosis worldwide.
“Motor adaptation is something we do constantly, often without realizing it,” Dexheimer said. “If a gust of wind hits you, if someone bumps your arm, if the ground tilts slightly – your brain recalibrates your movement on a millisecond scale. We want to know which brain regions make that possible, and what happens when that system isn’t working as it should.”
A new look inside the brain
This interdisciplinary study is possible because some patients with severe essential tremor opt for deep brain stimulation (DBS) surgery, a procedure that places a small electrode in deep structures of the brain. The device delivers therapeutic stimulation that can reduce tremor by as much as 80%. It also has the powerful capability to record neural activity from regions that cannot be reached by traditional imaging.
“That opens an incredibly rare research window,” Dexheimer said. “We can observe real-time electrical signals from the thalamus while a person is actively adapting their movement. That’s something we simply can’t capture with surface electrodes or conventional scans.”
Individuals selected for the study will complete a well-established computer-based motor adaptation task – “almost like an optical illusion,” Dexheimer said – while researchers record data directly from their implanted neural device. The team hopes to identify patterns that distinguish healthy motor adaptation from impaired adaptation in essential tremor.
Looking beyond tremor to hidden challenges
Dexheimer believes essential tremor’s impact might be far more complex than the shaking that defines its name. Many people experience difficulties with fine motor control that clinicians often attribute solely to tremor. But Dexheimer suspects deeper neurological disruptions.
“We’re learning that some individuals have underlying motor adaptation deficits that tremor might mask,” she said. “If that’s true, we need to be treating more than the tremor itself. We need a more complete picture of how essential tremor affects a person’s day-to-day function.”
Identifying electrophysiological “signatures” of those deficits could someday help clinicians diagnose them earlier, design rehabilitation interventions tailored to each patient, or even guide neurosurgeons as they optimize DBS programming.
This pilot grant will support one year of early data collection and analysis, setting the groundwork the team hopes will lead to larger, federally funded studies.
Building on a growing research trajectory
Dexheimer’s new project complements research she is conducting as part of a national team on a more than $2 million collaboration, funded by the National Institutes of Health, on motor learning and the effects of brain stimulation in people with neurological diseases. Her work has revealed unexpected patterns in how different patients might be diagnosed and how motor impairments are identified — raising new questions about the neurological underpinnings of motor control.
Together, the two projects reflect a unifying goal for Dexheimer’s Novel Environments for Reducing Disability & Dysfunction (NERDD) Lab. She is working to map the network of brain regions – from the basal ganglia to the cerebellum to the thalamus – that support movement, and understanding how disruptions in those regions reshape a person’s ability to participate fully in daily life.
“Parkinson’s disease, stroke, essential tremor – each tells us something about how the brain controls movement,” she said. “It’s like assembling a puzzle. Every patient population gives us another piece.”
Toward the future of diagnosis and rehabilitation
While Dexheimer is careful not to oversell what this new pilot project can accomplish, she is clear-eyed about its potential.
“If we can pinpoint how essential tremor affects motor adaptation – and identify the brain signals involved – that opens entirely new doors,” she said. “We could detect problems earlier. We could create better rehabilitation strategies. We could help more people maintain independence in meaningful daily activities.
“And if we do this right,” she added, “it will give us plenty of new questions to ask in the coming year.”