Figure 2

Diattenuation images of coronal and sagittal brain sections (60 μm thickness). (a) Mouse brain (left) and rat brain (right) measured with an effective object-space resolution of 14 μm/px. (b) Vervet monkey brain measured with an effective object-space resolution of 27 μm/px. The coronal (sagittal) section planes are indicated by blue (red) lines in the respective other brain section for reference. Regions surrounded by a white rectangle are shown as enlarged views. The strength of diattenuation \(|{\mathscr{D}}|\) is shown in green (magenta) for regions with diattenuation of type D⁺ (D⁻), cf. Figure 1c. The measurements were performed with the LAP one day after tissue embedding (see Methods). Selected anatomical structures are labelled according to rat³² and vervet³³ brain atlases. Regions with D⁻ mostly belong to regions with flat fibre structures (with respect to the section plane), regions with D⁺ mostly belong to regions with steep fibre structures (cf. also Menzel et al.³⁵ Fig. 1).