Rostral Midbrain

Question 1

Superior colliculus

Answer 1

Involved in visual attention and eye movements. Inputs from the retina and visual cortex reach it through the brachium of the superior colliculus.

Question 2

Periaqueductal gray

Answer 2

Site of origin of the descending pain control pathway that relays in raphe nuclei of the rostral medulla and caudal pons (among other connections).

Question 3

Cerebral aqueduct

Answer 3

Continuous rostrally with the third ventricle and caudally with the fourth ventricle.

Question 4

Brachium of the inferior colliculus

Answer 4

Ascending auditory fibers on their way from the inferior colliculus to the medial geniculate nucleus of the thalamus.

Question 5

Spinothalamic pathway

Answer 5

Mostly crossed fibers of second-order spinal neurons conveying pain and temperature information to the thalamus, reticular formation, and midbrain. At this level, it also includes a contribution from the spinal trigeminal nucleus.

Question 6

Medial lemniscus

Answer 6

The principal ascending pathway for tactile and proprioceptive information. Originates in the contralateral posterior column nuclei and terminates in the thalamus (VPL). At this level, it also includes a contribution from the trigeminal main sensory nucleus on its way to VPM.

Question 7

Reticular formation

Answer 7

No description.

Question 8

Last of the medial longitudinal fasciculus (MLF)

Answer 8

Conveying information from vestibular nuclei and abducens interneurons to the oculomotor nucleus.

Question 9

Oculomotor nucleus

Answer 9

Lower motor neurons for most extraocular muscles. LR6(SO4)3—GSE.

Includes Edinger-Westphal nucleus (separate card).

Question 10

Substantia nigra (reticular part)

Answer 10

Inputs from the caudate nucleus and putamen, outputs to the thalamus and other sites.

Question 11

Substantia nigra (compact part)

Answer 11

Dopaminergic neurons whose axons terminate in the caudate nucleus and putamen.

Question 12

Red nucleus

Answer 12

Interconnected with cerebellar circuitry, and the source of the small rubrospinal tract.

Question 13

Ventral tegmental area

Answer 13

Dopaminergic neurons whose axons terminate in limbic and frontal cortical sites.

Question 14

Corticopontine fibers

Answer 14

From ipsilateral cerebral cortex, in the cerebral peduncle.

Question 15

Corticospinal and corticobulbar fibers

Answer 15

From ipsilateral precentral gyrus and adjacent cortical areas.

Question 16

Oculomotor nerve fibers

Answer 16

No description.

Question 17

Edinger-Westphal nucleus

Answer 17

Preganglionic parasympathetic component of the oculomotor nucleus, supplying the papillary sphincter and the ciliary muscle. Small pupil, round lens. GVE.

Part of oculomotor nucleus (separate card).