Functional Imaging in Stroke Rehabilitations

van Donkelaar Lab

It is common to see variability in outcomes with stroke rehabilitation. In order to provide better treatment paradigms for individuals with strokes it is imperative that possible causes for the differences in outcomes are investigated. The manner in which an individual used their hand prior to stroke, for example dominant hand versus non-dominant hand, may impact recovery. The van Donkelaar lab (http://www.uoregon.edu/~paulvd/lab/eye_research.html) is interested in characterizing changes in the pattern of activation in the sensorimotor areas of the brain in individuals with stroke who have undergone an intensive form of rehabilitation called constraint-induced therapy (CIT) and correlate cortical activity with behavioral outcome. Our hypothesis is that the behavioral and neurological response to CIT will be constrained by the whether the damaged hemisphere is contralateral or ipsilateral to the dominant hand. The figure below displays a typical change in brain activation during affected hand movement in a patient with their dominant hand affected prior to and after CIT. This individual also demonstrated functional gains.

In addition we have examined how healthy individuals that are strongly right handed, strongly left handed or ambidextrous respond to restraining their more dominant hand for two weeks. This allows us to further understand how handedness impacts cortical and functional changes without the variability caused by differences in lesion size and location in individuals with stroke. The figure below displays a typical change in brain activation during nondominant hand movement in a strongly left handed individual prior to and after CIT.

Stroke is one of the leading causes of disability in the U.S. Recently, CIT has started being used to improve upper limb function even in patients with chronic motor deficits. It is advantageous to understand who responds well to this type of rehabilitation technique. This research will help to inform clinicians and rehabilitation specialists and provide a basis for more individualized treatment interventions for patients suffering from stroke.