Fig. 4.

Second dimension of the cingulum fasciculus Isomap. (Top) Moving average shapes (MAS) along the Isomap axis observed with 2 different orientations (for each orientation, the frontal horn of the bundle is on the left). The extreme MAS (green and magenta) are combined to highlight the shape feature encoded by the Isomap. This dimension captures a pure shape feature. From the left to the right of the Isomap axis, the volume of the frontal extremity increases while the volume of the parietal extremity decreases. (Middle) Distributions along the Isomap axis of the left bundles of patients with bipolar disorder versus controls superimposed over the same MAS. (Bottom) Cingulum sample and the corresponding uncinate fasciculus and overall and centre-based boxplots of the localization in the isomap after adjustment for fractional anisotropy, age and sex.