PhD defence - Jesper Lundbye-Jensen

Investigations of central nervous plasticity accompanying motor learning and immobilization in humans

Plasticity is one of the fundamental properties of the central nervous system (CNS) in the sense that neural activity in our brain and spinal cord is modulated by experience throughout life. This enables the CNS to adapt and adjust to the actual demands. In the case of motor learning, neural plasticity enables us to acquire and retain new skills but plasticity may also occur in response to physical inactivity, trauma or pathology.

The thesis constitutes a summary and conjunction of the results obtained in seven experimental studies, which aimed at investigating how plastic changes within the intact CNS accompany and most likely form the underlying basis of the behavioural changes, which may be observed following motor learning, training (activity) and immobilization (inactivity). The experimental work relies primarily on behavioral measures and measurements obtained through noninvasive electrophysiological and neuroimaging techniques.

The thesis consists of an introduction to the areas of motor control and neuroplasticity followed by the presentation and discussion of the results obtained in the included studies. From a basic research perspective, the results contribute to the basic understanding of mechanisms of plasticity and the relationship between plasticity and behavior. One main goal of the thesis was to extend the focus of neuroplasticity to the entity of the CNS.

The results demonstrate changes at multiple levels within the CNS and in the coupling between structures. In order to understand behavioral implications, it thus seems necessary to study neuroplasticity at multiple levels. The experiments only concern effects of learning and immobilization in the healthy CNS. It does however seem likely that the observed phenomena are relevant in a context of (neuro)rehabilitation. From an applied perspective, the findings may be of use in order to develop strategies to enhance motor learning also in a context of rehabilitation and diminish degrading effects of inactivity or immobilization

Time

Friday the 12 March 2010 at 14.00 o'clock

Place

Department of Exercise and Sport Sciences, Henrik Dam Auditoriet, Panum Insituttet, Blegdamsvej 3, DK-2200 Copenhagen N

Opponents

Professor Richard Carson, School of Psychology, Queens University, 
Belfast, United Kingdom 

Professor Thomas Sinkjær, The Danish National Research Foundation 
(Danmarks Grundforskningsfond), Copenhagen, Denmark 

Professor Bente Kiens, Department of Exercise and Sport Sciences, 
University of Copenhagen, Denmark (chairman) 

Supervisor

Professor Jens Bo Nielsen, Department of Exercise and Sport Sciences,
Faculty of Science, University of Copenhagen, Denmark