Medulla is a cone-shaped structure in lower brainstem, anterior to cerebellum. Divided into upper open and lower closed parts with fourth ventricle. Contains pyramidal tracts in medullary pyramids, which cross at decussation. Features olivary bodies in upper part and gracile/cuneate tubercles in posterior
Cerebral cortex is outer layer of neural tissue in cerebrum. Contains 14-16 billion neurons organized into horizontal layers. Divided into four major lobes: frontal, parietal, temporal, occipital. Cortex is folded into gyri (peaks) and sulci (grooves). Human cortex is 2-4 mm thick, making up 40% of brain mass
MCA arises from internal carotid artery and supplies lateral cerebral cortex. Divides into four segments: sphenoidal, insular, opercular, and cortical. Supplies anterior temporal lobes and insular cortices. Connects to anterior cerebral arteries and posterior communicating arteries
Divides body into right and left sections perpendicular to transverse and coronal planes. Term "sagittal" comes from Latin "sagitta" meaning arrow. Can be mid-sagittal (through center) or para-sagittal (away from center)
Located at back of head, part of posterior cerebrum. Contains primary visual cortex (Brodmann area 17). Divided into cuneus (above medial sulcus) and lingual gyrus (below). Resting on tentorium cerebelli separating cerebrum from cerebellum
Gyrus is a ridge on cerebral cortex surrounded by sulci. Gyri and sulci create folded appearance of mammalian brains. Folds allow larger cortical surface area in smaller skull. Brain undergoes gyrification during fetal and neonatal development