has part has part has_part continuous with contributes to morphology of brain medulla oblongata midbrain tegmentum spinal cord brainstem http://upload.wikimedia.org/wikipedia/commons/b/b7/Gray719.png 'brainstem' is a loose term that sometimes refers to the ventral parts o the brain except for any part of the telencephalon - sometimes it includes the diencephalon or subpallial telencephalon structures (ISBN:0471888893). Here we use it in a more restriced sense, to include only the medulla oblongata, pons (when present) and the midbrain tegmentum (following the ZFA definitions). regional part of brain