Neuroanatomy Draw It To Know It

9. Brainstem—Part One 153

Cortico-

nuclear

tract

Cortico-

spinal

tract

Fronto-

pontine

tract

Addl.

cortico-

pontine

tracts

(Crus

cerebri)

Substantia

nigra

Red

nucleus

(mid-/upper

midbrain)

*Cranial nerve

nuclei: 3, 4, (5)

Periaqueductal

gray

Cerebral

aqueduct

Superior cerebellar peduncle

fiber decussation

(lower midbrain)

NUCLEI Posterior commissure TRACTS

Posterior

Left

Anterior

Right

(Red

nucleus)

LL = Lateral lemniscus

ALS = Antero-

lateral system

Medial

lemniscus

AT = Ant. trigemino-

thalamic tract

AT

LL

ALS

Tectospinal

tract

Central

tegmental

tract

Colliculi:

superior

& inferior

Reticular

formation

Raphe

nuclei

Tegmentum

Basis

Tectum

M

L

F

Post. trigemino-

thalamic tract

MLF = Medial longitudinal

fasiculus

*Note: cranial nerves

3 & 4 lie in midline

DRAWING 9-3 Th e Midbrain — Complete