Events

Public defence in Biomedical Engineering, M.Sc. (Tech) Julia Jaatela

Imaging the brain’s white matter structure unveils the neural basis of cerebral palsy, the most prevalent childhood motor syndrome. Public defence from the Aalto University School of Science, Department of Neuroscience and Biomedical Engineering.
Kuva esittää kahta aivopuoliskoa, joista vasemmassa näkyy valkean aineen ratoja ja oikeassa aivokuoren uurteita.
Image: Paula Ikonen

Title of the doctoral thesis: Investigating the white matter structure of the sensorimotor system in children with cerebral palsy

Doctoral student: Julia Jaatela
Opponent: Prof. Christos Papadelis, University of Texas at Arlington, USA
Custos: Prof. Lauri Parkkonen, Aalto University School of Science, Department of Neuroscience and Biomedical Engineering

Cerebral palsy (CP) is caused by damage in the developing brain leading to impaired movement control, muscle coordination, and balance. In hemiplegic CP, the sensory and motor dysfunctions are located on one side of the body, whereas in diplegic CP, dysfunctions are emphasized on the lower limbs. CP is, however, a heterogenous disorder and each individual presents a unique clinical profile. The precise interconnection between changes in brain structure and impaired functionality remains not fully understood. 

It has been shown that CP is associated with changes in the brain's white matter. The white matter consists of long extensions of nerve cells that bundle together to form pathways facilitating efficient communication between different brain regions. These white matter pathways can be examined using diffusion-weighted magnetic resonance imaging that illuminates the arrangement of nerve fibers along a specific pathway. This method enables the detection of subtle structural changes that may not be visible with traditional brain imaging. 

This doctoral dissertation focused on two major neural pathways. The largest white matter pathway, corpus callosum, links the two hemispheres of the brain, while the thalamocortical pathway transmits sensory signals from the body to the cerebral cortex. For the first time, these brain pathways were compared between hemiplegic and diplegic CP groups. Additionally, a novel approach was introduced to distinguish pathways carrying sensory information from either the upper or lower limbs. The results revealed structural changes in the examined pathways for both CP groups. In hemiplegic CP, the structural alterations appeared more pronounced, yet relatively confined, compared to diplegic CP. Although the white matter structure correlated to some extent with motor function, the connection was weak, underscoring the complexity of the brain’s structure-function relationships. 

The dissertation contributes significantly to our understanding of the neural basis of CP and offers important insights also into the brain organization of typically developing children. The results and approaches presented in the study could potentially guide individual diagnosis and rehabilitation strategies for CP in the future. Importantly, a better understanding of CP enhances our comprehension of the brain's capacity to develop and adapt following a brain injury.

Thesis available for public display 10 days prior to the defence at: https://aaltodoc.aalto.fi/doc_public/eonly/riiputus/

Doctoral theses in the School of Science: https://aaltodoc.aalto.fi/handle/123456789/52

  • Published:
  • Updated: