Only adhil’s i haven’t added tanya’s stuff yet.

Brainstem is sitting on the ventral surface and consists of midbrain, pons and medulla oblongata

Medulla oblongata houses crucial autonomic (not in conscious control of it) centers e.g. breathing, heartbeat.

Midbrain is closely related to and forms caudal border of the diencephalon (Thalamus sits above midbrain). Pons is directly below the midbrain and medulla is directly below the pons.

External features:

(removed cerebellum and looking down onto brainstem)

Dorsal surface (Cerebellar peduncles indicate we are looking at the dorsal surface, Rhomboid fossa indicates the dorsal surface):

these are the features of the dorsal surface)

Midbrain region

• Corpora quadragemini (4 bumps-2 superior and 2 inferior colliculus)- very distinuishing feature of the midbrain)
• Trochlear nerve (CN IV)- only cranial nerve emerging on dorsal surface

Pons region

• Cerebellar peduncles
• Floor of the 4th ventricle

Medulla region

• Dorsal median sulcus
• Continuation of dorsal columns of  spinal cord
• Fasciculus cuneatus
• Fasciculus gracilis

Ventral surface: