The "halo" around the edges is actually from the edge of the window where the glass on top of the brain meets the skull. The vertical stripe on the left is the central sagittal sinus. This is the big vein which runs along the middle of the brain. Humans also have this.
These image span a region about 5 mm wide. Our usual movies are about 0.5 mm across.
Sorry about this. You can flag these movies to help us find the error.