PhD defence: Oscillatory brain and spinal connectivity underlying human ankle movement and stepping
Meaghan Elizabeth Spedden
PhD thesis
The work in this thesis aims to study the way different regions in the central nervous system (CNS) interact during voluntary ankle movement and walking in humans.
Our ability to walk, and precisely adapt our steps according to the environment, is a fundamental motor behavior for us as humans.
The way the human CNS controls these behaviors is not well understood; a lot of what we know about the control of movement is based on studies of upper-limb movements like reaching or finger tapping, and prior work has focused on understanding contributions from CNS regions from an isolated rather than integrated perspective.
Understanding how CNS regions communicate during lower limb movements and walking will further our understanding of basic functional control mechanisms and in the long term may provide a basis for developing evidence-based rehabilitation strategies.
The five studies included in this thesis aim to investigate the communication and interaction between different regions of the human CNS during simple ankle movements and during more complex and functional stepping movements.
We used frequency domain connectivity analysis and modelling approaches to study interaction between the brain and ankle muscle extit{tibialis anterior}, as well as among different brain regions using electroencephalography (EEG), magnetoencephalography (MEG), and electromyography (EMG).
The results suggest that the strength of connectivity is related to force control in a complex manner, which indicates that it has functional significance. Further, connectivity strength exhibits age-related differences across childhood development and adult aging, suggesting that this connectivity may represent a maturational phenomenon.
Download Summary; Dansk resumé; Overview of studies; Contents.
2022, 200 pages.
Date
30 September 2022, 14:00
Place
Store Auditorium, Nørre Allé 53, DK-2200 Copenhagen and online.
Opponents
Associate professor Eva Wulff Helge (chair), Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark.
Professor emeritus Bernard Conway, University of Strathclyde, Glasgow, Scotland.
Associate professor Andrew Stevenson, Department of Health Science and Technology, Aalborg University, Denmark.
Supervisor
Associate professor Jesper Lundbye-Jensen, Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark.
Co-supervisors
Professor Jens Bo Nielsen, Department of Neuroscience, University of Copenhagen, Denmark.
Dr. Simon Farmer, Department of Clinical Neurology, The National Hospital for Neurology and Neurosurgery, London, UK.