1. Gross anatomy and development of the brain stem and cerebellum. Fourth ventricle Dr GallatzKatalin

2. The brain • Telencephalon • Diencephalon • Cerebellum • Brain stem

3. Parts of the brain stem • Mesencephalon • Pons • Medulla

4. Ventral surface of the hypothalamus and brainstem 1. cerebral peduncle 2. interpeduncular fossa 3. oculomotor nerve 4. optic tract 5. pons 4 5 5 3 1 2 4 5

5. Dorsal surface of the diencephalon and brainstem sc – superior colliculus, ic – inferior colliculus, scp – sup. cerebellar peduncle th sc ic scp pons medulla

6. Brain Stem Midbrain Cranial Nerve III., IV. • pupillary reflex • eye movements

7. The midbrain or mesencephalon (from the Greek mesos – middle, and enkephalos) - is associated with vision, hearing, motor control, pain control sleep/wake, and temperature regulation

8. Parts of the mesencephalon • - tectum • inferior colliculi • superior colliculi • - cerebral peduncle • tegmentum • crus cerebri

9. Midbrain Ventral surface • Crus cerebri (1) • Interpeduncular fossa (2) oculomotor nerves(3) • Posterior perforated substance 3 1 2

10. Midbrain MGB Dorsal surface • Superior colliculus(1) constitute centers for visual reflexes • Inferior colliculus(2) associated with auditory pathway • Brachium of superiorcolliculus LGB • Brachium of inferior colliculus MGB LGB 1 trochlear n. 2 scp

11. Brain Stem • Pons • Cranial Nerves V., VI., VII.

12. Parts of the pons • tegmentum – dorsal surface • base –venral surface

13. pontine tegmentum base

14. Pons Ventral surface • Basilar sulcus • Pontomedullary junction: from medial to lateral, abducent, facial and vestibulocochlear nerves Middle cerebellar peduncle • Trigeminal nerve • Pontocerebellar trigone: the junction of medulla, pons and cerebellum

15. Pons Dorsal surface • Medial eminence(1) • Facial colliculus(2) • Locus ceruleus(3) 1 3 2

16. Brain Stem • Medulla Cranial Nerves IX, X, XI, XII • Pharyngeal (Gag) Reflex • Tracheal (Cough) Reflex • Cardiovascular, respiratory centers

17. Parts of the medulla • opened part – rostral part • closed part – caudal part dorsal surface ventral surface

18. Medulla oblongata ventral surface • Pyramid: contain pyramidal tract(corticospinal tract) • Decussation of pyramid: formed by crossing fibers of corticospinal tract • Olive: inferior olivary nucleus • Medial parolivary sulcus hypoglossal nerve Lat. parolivary sulcus:glossopharyngeal, vagus accessory nerves

19. Medulla oblongata Dorsal surface • Caudal portion • Gracile tubercle: produced by underlying gracile nucleus • Cuneate tubercle: marks the site of cuneate nucleus • Inferior cerebellar peduncle • Obex • Rostral portion: • forms the caudal half of rhomboid fossa

20. Fourth ventricle Position • Situated ventral to the cerebellum, and dorsal to the pons and cranial half of medulla

21. Borders of the rhomboid fossa – floor of the fourth ventricle • Inferolateral: inferior cerebellar peduncle • Superolateral: superior cerebellar peduncle • Lateral recess

22. Rhomboid fossa – floor of the fourth ventricle • Facial colliculus, medial eminence • Hypoglossal trianglehypoglossal nucleus • Vagal triangle: dorsal nucleus of vagusnerve • Funiculus separans • Area postrema • Locus ceruleus

23. Roof of the fourth ventricle • Anterior part: formed by superior cerebellar peduncle and superior medullary velum • Posterior part: formed by inferior medullary velum,tela choroidea and choroid plexus of fourth ventricle • Three apertures Median aperture(Magendi) Two lateral apertures(Luschka)

24. Position of the cerebellum • It lies in the posterior cranial fossa • The tentorium cerebelli separates it from the occipital lobe of the cerebrum

25. Cerebellar peduncles - Inferior cerebellar peduncle(1)connects it with medulla - Middle cerebellar peduncle(3)connects it with pons, - Superior cerebellar peduncle(2)－connects it with midbrain, 1 2 3

26. External features Consists of twocerebellar hemispheres united in the midline by the vermis

27. Lobes and fissures of the cerebellum • Two deep fissures • Primary fissure • Posterolateral fissure • Horizontal fissure • Three lobes • Flocculonodular lobe flocculus and nodule • Anterior lobe • Posterior lobe

29. Lobs Anterior lobe Primary fissure Posterior lobe Flocculonodular lobe Posterolateral fissure

30. Internal structures Cerebellar nuclei Fastigial nucleus Globose nucleus Dentate nucleus Emboliform nucleus Cerebellar cortex

31. Functional divisions • Vestibulocerebellum • Archicerebellum • Flocculonodular lobe • Spinocerebellum • Paleocerebellum • Vermis and intermediate zone • Cerebrocerebellum • Neocerebellum • Lateral zone Intermediate zone Vermis Lateral zone Flocculonodular lobe

32. Development of the brain

35. Thank you for your attention!