Fig. 2.

Results from the functional (A) and effective (B) connectivity analyses of patients with cervical dystonia (CD) and the effects of treatment with botulinum toxin (BNT).

Schematic representation of (A) functional connectivity (FC) and (B) Granger causality (GC) in resting-state fMRI from (left panels) the controls compared with the patients with CD (naive to treatment with BNT) and (right panels) the patients with CD who were treated without (naive) and with BNT (6 months). The results for the comparisons between patients with CD and controls (independent samples) and between patients with CD before and after BNT treatment (dependent samples) were corrected for multiple comparisons using a Bonferroni/FWE correction. In the figure, the lines indicate increased connectivity between specific brain regions; in GC, the direction of the arrow indicates the direction of the effective connectivity. A / left panel: in controls, FC between S1/S2 is increased; in patients with CD, increased connectivity within the BG, the thalamus, the motor cortex, and S2 is observed. A / right panel: the connectivity between S1/S2 is increased in patients with CD following BNT treatment; before the BNT application, the FC between the putamen and the thalamus, the STN, and the motor cortex is increased. B / left panel: in patients with CD, increased coupling of the putamen towards the pallidum and S2, S2 towards the motor cortex, and STN towards the thalamus is observed; increased autonomy in the pallidum and the thalamus is also detected. B / right panel: increased coupling of the motor cortex towards the caudate nucleus is observed in patients with CD following the BNT application; before the BNT application, increased GC exists between the putamen and the thalamus towards S2 and increased autonomy of the STN.