Author response image 2. Interpolation to fill gaps in and recover a thin substructure.

(A) A thin extension in the medial pallium (green structure) in the P4 atlas is missing sagittal annotations in planes 152 and 155, visible as two gaps in the axial and coronal view, as well as gaps between the extension and the rest of the structure in planes 151, 154, and 155. (B) Reconnecting this extension (left) and interpolating between the edited planes fills the gaps as seen in the axial view (middle), recovering this thin substructure in the final smoothed atlas. (C) This substructure is apparent in the anterior section of the original atlas (left) but lost in the 3D reconstructed atlas (middle), although the rest of the medial pallium is present in other planes. After interpolation and 3D reconstruction, the substructure is recovered (right).