Open Access Senior Thesis
Bachelor of Science
Strokes are the result of restricted blood flow to particular areas of the brain classified by their cause. The neural damage they cause are of growing concern as the number of young adults experiencing strokes has increased by 11% in the last decade. Following stroke, there is an imbalance of inhibitory and excitatory neuronal activity, and disruption of neural networks. These changes lead to neuronal death and loss of synaptic connections that, depending on which part of the brain is affected, result in behavioral deficits such as weakness, limb hemiparesis, and loss of coordination, as well as speech and cognitive impairments. However, this loss of function can be partly recovered due to neuroplastic processes. Non-invasive brain stimulation (NIBS) is an approach that involves implanting electrodes into targeted areas of the brain which are connected to an implantable pulse generator on the skin that delivers chronic electric pulse. There are different forms of stimulation, but one with some established success in improving upper and lower limb mobility, as well as some cognitive symptoms, is transcranial direct current stimulation (tDCS). For the treatment of stroke, tDCS aims to increase excitability of the lesioned areas to improve contralesional mobility. While past research has focused on stimulating well established motor regions, such as the cerebellum, motor cortex, and basal ganglia, sensory systems also play a key role in sending information through the ascending dorsal column medial lemniscal pathway, posterior and anterior spinocerebellar tracts, and spinoreticular tracts. Here is a review of the current research on the integration of sensory and motor information in order to carry out desired movement, a discussion about how these networks are being targeted by tDCS after stroke to help patients regain lower limb movement, and finally, a proposed study in which improvements in balance, gait, and postural stability after anodal tDCS continue up to a year post-treatment in chronic ischemic stroke patients.
Fantz-Sands, Jessica, "Transcranial Direct Current Stimulation (tDCS) to Improve Lower Limb Motor Recovery Following Stroke: A Review and Study Proposal" (2023). Scripps Senior Theses. 2024.