Page 66 - Bladder Dysfunction in the Context of the Bladder-Brain Connection - Ilse Groenendijk.pdf
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Chapter 3
per single subject and denoised for signal arising from white matter, grey matter and cerebrospinal fluid using linear regression. Furthermore, the task model was added as a regressor of no interest. Connectivity was defined as the linear correlation between time series of different ROIs, which was computed with the Pearson’s correlation coefficient. Single subject correlation matrices were used to compute a mean correlation matrix.
To assess the overlap of clusters of both tasks in specific brain areas, the dice index was calculated using the extracted ROI’s of the single subjects. The dice index was calculated for overlap in the M1, SMA, insula and cerebellum ROIs.
RESULTS
The scanning protocol was completed in all 17 subjects. Data concerning 4 subjects was excluded due to motion artefacts (>1mm displacement), yielding a total of 13 subjects for in-depth analyses.
Single subject and group analyses following pelvic floor muscle contraction
PFMC resulted in significant activation of various different brain regions following analy- ses of both single subjects and groups (for group results: Table 1). The superomedial primary motor cortex (M1) was activated in all subjects. In the group analysis this cluster was split into two separate clusters, one more anterior and the other more posterior on M1 (Fig. 1). Moreover, on M1, a second, more inferolateral cluster was found bilaterally in 11/13 subjects. This inferolateral M1 cluster was also activated bilaterally in the group analysis (Fig. 1). In 11 subjects’ active clusters were found in the putamen (8 bilateral/3 unilateral). Thalamus activation was found in 10 subjects (5 bilateral/5 unilateral). In group analysis this resulted in combined activation of the putamen and the thalamus in both hemispheres (Fig. 2). Concerning the cerebellum, activation in lobule IV was seen bilaterally in 7 subjects and unilaterally in 1 subject (indicated by circles, Fig. 3). More posterior, in lobule VI, an active cluster was found bilaterally in 6 subjects and unilateral in 5 subjects (Fig. 3). In the posterior lobe of the cerebellum, specifically in lobule VIII, active clusters were found during PFMC in 2 subjects bilaterally and in 6 subjects unilat- erally (data not shown). In the group analysis, cerebellar activation was found in lobule IV bilaterally, comparable to the single subject results. The cluster seen in single subjects in lobule VI was found unilateral in the left hemisphere of the cerebellum in the group analysis. Group analysis did not show activation in lobule VIII.
Connectivity analyses following pelvic floor muscle contraction
Connectivity analysis was performed in the nine individuals who showed active voxels in all ROIs except for the thalamus, the activity of which was not present in a sufficient

























































































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