Gray matter differences contribute to variation in cognitive performance in Parkinson's disease
Article first published online: 21 SEP 2013
© 2013 The Author(s) European Journal of Neurology © 2013 EFNS
European Journal of Neurology
Volume 21, Issue 2, pages 245–252, February 2014
How to Cite
Gerrits, N. J. H. M., van der Werf, Y. D., Hofman, M., Foncke, E. M. J., Klein, M., Berendse, H. W. and van den Heuvel, O. A. (2014), Gray matter differences contribute to variation in cognitive performance in Parkinson's disease. European Journal of Neurology, 21: 245–252. doi: 10.1111/ene.12269
- Issue published online: 13 JAN 2014
- Article first published online: 21 SEP 2013
- Manuscript Accepted: 23 AUG 2013
- Manuscript Received: 18 APR 2013
- cognitive deficits;
- Parkinson's disease;
- structural MRI;
- voxel-based morphometry
Background and purpose
A substantial proportion of patients with Parkinson's disease (PD) suffer from cognitive deficits, although there is a large variability in the severity of these impairments. Whilst the cognitive deficits are often attributed to monoaminergic changes, there is evidence that alterations in structural brain volume also play a role. The aim of our study was to gain more insight into the variability of cognitive performance amongst PD patients by examining the relation between regional gray matter (GM) volume and cognitive performance.
Linear regression analyses were performed between task performance and GM volume for six neuropsychological tasks within a group of 93 PD patients; they were additionally compared at a group level with matched healthy controls, using voxel-based morphometry.
Our most important findings were positive correlations between GM volume and cognitive performance for (i) parahippocampal gyrus and verbal memory, (ii) medial temporal lobe and putamen and visuospatial memory, and (iii) middle temporal gyrus and frontal lobe and verbal fluency. In addition, decreased GM volume was found in the frontal, parietal and temporal cortices of PD patients compared with matched healthy controls.
It is argued that the large variability in cognitive function across PD patients is partly mediated by GM volume differences in the implicated areas. Volume differences in these brain regions do not discriminate between patients and controls but explain cognitive variation within the patient population.