Anatomy of the midbrain

Tectum
(Dorsal)

Corpora quadrigemina

Pretectal area

Sensory / ascending	Spinotectal tract Central tegmental tract
Motor / descending	Tectospinal tract

Cerebral aqueduct

Peduncle
(Ventral)

Sensory / ascending	Lemnisci Medial Lateral Ascending MLF Vestibulo-oculomotor fibers Spinothalamic tract Anterior trigeminothalamic tract Dentatothalamic tract
Motor / descending	Rubrospinal tract Rubro-olivary tract Descending MLF

cranial nuclei	GSA Mesencephalic GSE Oculomotor nucleus Trochlear nucleus GVE Edinger–Westphal nucleus
Ventral tegmental area	Rostromedial tegmental nucleus
Periaqueductal gray Red nucleus Rostral interstitial nucleus of medial longitudinal fasciculus Parabrachial area Interpeduncular nucleus
Midbrain reticular formation	dorsal tegmental nucleus Raphe nuclei dorsal Reticulotegmental nucleus

Base

White / Cerebral crus	Corticospinal tract Corticobulbar tract Corticopontine tract Frontopontine fibers Temporopontine fibers
Grey / Substantia nigra	Pars compacta Pars reticulata
Surface	Superior cerebellar peduncle Decussation Interpeduncular fossa

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