Brain activation following constraint-induced movement therapy using functional near infrared spectroscopy in stroke patients
Based on the learned non-use theory, constraint-induced movement therapy (CIMT) is a rehabilitation technique that is utilized with stroke patients to regain function of an affected extremity. CIMT provides patients the resources to help enhance their reliance on an impaired limb while constraining the intact limb. Over time, the impaired limb gains strength and is able to effectively challenge its learned non-use during daily living tasks (Grotta et al., 2004; Taub, Uswatte, & Pidikiti, 1999). Research suggests the use of CIMT has shown to be significantly effective in chronic stroke patients’ ability to improve function in the use of an impacted limb (Grotta et al., 2004; Kunkel et al., 1999; Liepert et al., 1998). In addition, neuroimaging studies have demonstrated that CIMT influences the reorganization of the brain (Levy, Nicholas, Schmalbrock, Keller, & Chakeres, 2001).
Functional Near-Infrared Spectroscopy (fNIRS) is an novel method of mapping the brain by using light to measure changes in oxygenated and de-oxygenated hemoglobin concentration in cortical tissue (Nishimura, Rapoport, Wubbels, Downs, & Downs, 2010). Research employing imaging technology to investigate functional and neurological recovery following brain injury is essential in understanding the implication of various neurorehabilitation methods. Furthermore, additional research is necessary to validate the sensitivity of fNIRS in detecting changes in brain activity, such as the motor cortex. The purpose of this study was to utilize fNIRS to explore cortical activation patterns in stroke patients before and after neurorehabilitation. More specifically, the study examined hemoglobin signal among patients who experienced hemiparesis after a left middle cerebral artery (MCA) stroke. Participants’ upper extremity motor functioning following two weeks of CIMT was examined to determine if CIMT during stroke rehabilitation is associated with changes in neural activity.