In this thesis, the consequences of Parkinson’s disease (PD) are studied using advanced approaches in neuroimaging, including structural as well as functional connectivity networks, examination of... Show moreIn this thesis, the consequences of Parkinson’s disease (PD) are studied using advanced approaches in neuroimaging, including structural as well as functional connectivity networks, examination of the role of aging in white matter degeneration in PD, and the use of machine learning classification models. Brain MRI features of PD patients are compared with healthy control subjects, and the relations between these features and patient characteristics, such as age, dopaminergic medication, motor and predominantly non-dopaminergic impairment, are described. Furthermore, brain features that may contribute to the differentiation of PD and Dementia with Lewy body dementia are described. Show less
Koini, M.; Duering, M.; Gesierich, B.G.; Rombouts, S.A.R.B.; Ropele, S.; Wagner, F.; ... ; Schmidt, R. 2018
Loss of grey-matter volume with advancing age affects the entire cortex. It has been suggested that atrophy occurs in a network-dependent manner with advancing age rather than in independent brain... Show moreLoss of grey-matter volume with advancing age affects the entire cortex. It has been suggested that atrophy occurs in a network-dependent manner with advancing age rather than in independent brain areas. The relationship between networks of structural covariance (SCN) disintegration and cognitive functioning during normal aging is not fully explored. We, therefore, aimed to (1) identify networks that lose GM integrity with advancing age, (2) investigate if age-related impairment of integrity in GM networks associates with cognitive function and decreasing fine motor skills (FMS), and (3) examine if GM disintegration is a mediator between age and cognition and FMS. T1-weighted scans of n = 257 participants (age range: 20–87) were used to identify GM networks using independent component analysis. Random forest analysis was implemented to examine the importance of network integrity as predictors of memory, executive functions, and FMS. The associations between GM disintegration, age and cognitive performance, and FMS were assessed using mediation analyses. Advancing age was associated with decreasing cognitive performance and FMS. Fourteen of 20 GM networks showed integrity changes with advancing age. Next to age and education, eight networks (fronto-parietal, fronto-occipital, temporal, limbic, secondary somatosensory, cuneal, sensorimotor network, and a cerebellar network) showed an association with cognition and FMS (up to 15.08%). GM networks partially mediated the effect between age and cognition and age and FMS. We confirm an age-related decline in cognitive functioning and FMS in non-demented community-dwelling subjects and showed that aging selectively affects the integrity of GM networks. The negative effect of age on cognition and FMS is associated with distinct GM networks and is partly mediated by their disintegration. Show less
Coppen, E.M.; Grond, J. van der; Hafkemeijer, A.; Rombouts, S.A.R.B.; Roos, R.A.C. 2016
