Loonstra, F. (Floor) (2015) Exploring the neurobiological underpinnings of apathy: relationship between apathy and deactivation of the default mode network in schizophrenia patients. thesis, Medicine.
![[img]](https://umcg.studenttheses.ub.rug.nl/style/images/fileicons/text.png) |
Text
LoonstraF.pdf Restricted to Registered users only Download (936kB) |
Abstract
A critical component with regard to functional outcome in schizophrenia patients is apathy, characterized by lack of motivation and diminished goal-directed behavior. Since the default mode network (DMN) is involved in internally-directed cognitive function and attenuated during goal-directed activity, failure to suppress the DMN has been linked to several clinical features of schizophrenia. Here we suggest that apathy can be attributed to lack of DMN suppression. We hypothesized that schizophrenia patients with high apathy levels show less deactivation of the DMN during a task compared to patients scoring low on apathy. We investigated the association between apathy and DMN deactivation using arterial spin labeling in 46 patients with schizophrenia or psychotic spectrum disorder and 11 healthy controls, while performing the tower of London task during fMRI scanning. We used independent component analysis to identify DMN regions and to extract mean time courses from these corresponding components for both patients and controls. The time courses for the DMN components were plotted with apathy score as coloring and a scatterplot was used as a visual representation of the correlation. Our results demonstrated DMN deactivation during goal-directed activity. The DMN showed less activation during rest and less deactivation during the task in patients compared to controls during certain time points equally distributed between rest and task blocks. We were not able to detect a significant difference between patients and controls in modulating the DMN for most time points during the task, however. Moreover, we found no significant relationship between apathy and DMN deactivation. These results suggest that schizophrenia patients may show abnormalities in DMN operation compared to controls. However, research repeating our study needs to be performed considering our limitations (e.g., small sample size of control group and use of ASL instead of BOLD fMRI).
| Item Type: | Thesis (Thesis) |
|---|---|
| Supervisor name: | Aleman, Prof. dr. A. and Liemburg, Dr. E and Neuro Imaging Centre Groningen |
| Faculty: | Medical Sciences |
| Date Deposited: | 25 Jun 2020 10:59 |
| Last Modified: | 25 Jun 2020 10:59 |
| URI: | https://umcg.studenttheses.ub.rug.nl/id/eprint/1972 |
Actions (login required)
 |
View Item |