Starting stage.<br><br>Here you see a schematic of the brain (+ the top of the spinal cord) surrounded by its bone lining (faint light brown outline). The picture shows a frontal section through the large brain seen from the front (arrow) with underlying brainstem and cerebellum. 

Step 1.

Step 1<br><br>You can examine the step in different ways. For example, you first light lists 1 & 2, roll them out and orient yourself among the different structures (turn on/off in the list, point to the structure). Then, with lists 1 & 2 either turned on or off ("extinguished" is probably best the first time, but do whichever you think is best), you light up and open List 3. Here it is safest to systematically work your way from the top to the bottom of the list for the first time.

Artery supply of the brain: frontal section in front of the bridge and through the ventricular intercavity.