Figure 4. Streamlines from the right and left STN in subject 1, ending in the motor cortex, that do not pass through thalamus, caudate, putamen or globus pallidus.

These streamlines are therefore an indication for the existence of the “hyperdirect” pathway. (a) Coronal view. (b) Sagittal view on streamlines from the right STN. (c) Streamline rendering in 3D, showing an axial plane of the unweighted diffusion image.