Medula oblongata anatomy.

Brainstem
Last part of brain
The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem.[1] It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involuntary) functions, ranging from vomiting to sneezing.[2] The medulla contains the cardiac, respiratory, vomiting and vasomotor centers, and therefore deals with the autonomic functions of breathing, heart rate and blood pressure as well as the sleep wake cycle.
During embryonic development, the medulla oblongata develops from the myelencephalon. The myelencephalon is a secondary vesicle which forms during the maturation of the rhombencephalon, also referred to as the hindbrain.

The bulb is an archaic term for the medulla oblongata.[1] In modern clinical usage, the word bulbar (as in bulbar palsy) is retained for terms that relate to the medulla oblongata, particularly in reference to medical conditions. The word bulbar can refer to the nerves and tracts connected to the medulla, and also by association to those muscles innervated, such as those of the tongue, pharynx and larynx.

1. Medula oblongata Anatomy Dr upendra Bhardwaj Guide –dr. S. K. Tyagi. Hod, department of neurosurgery Indraprastha apollo hospital.

2. Bilaminar embrionic disc

3. Development of notochord

4. Formation of notochord

5. Formation of primary vesicles

6. External feature Anterior and posterior median fissure. Two anterolateral sulci . two posterolateral sulci . two longitudinal elevation pyramid. With pyramidal decussation. And anterior external arcuate fibre. two olive at upper part of lateral region. Due to inferior olivvary nucleus. two necueus gracilous two nucleus cunetious and there fasciculus and two inferior cerebellar peduncle. two hypoglosaal nerve exiting from both anteriorolateral sulci . two vagus and cranial part of spinal Acessory nerve and glossopharyngial nerve exiting from posteriorolateral sulci .

7. A v shaped depression which is tha lower part of fourth ventricle Which shows striae medullares at near the upper limit of medula marked by external arcuate fibre. Hypoglossal triangle Vagal triangle Vestibular area Inferior fovea Funiculus separans Area postrema Obex

8. . Below the floor of IV th ventral There is Fasciculus gracilis fasciculus fasciculus cuneatus and inferior cerebellar peduncle. Gracilis tubercles cuneatus tubercles. Tuber cinerium

9. Ventral surface

10. Dorsal surface

11. Dorsal surface

12. Internal structure Tracts 4 measure tract Corticosinal tract Dorsal column. Rail’ band Spinothalmic tract Spinocerebellar tract

13. Corticospinal or pyramidal tract

14. Dorsal column and anterolateral spinothamic tract

15. Spinocerebellar tract

16. Minor tracts Cuneocerebellar tract Olivocerebellar tract. spinoolivary tract. Arcuatocerebellar tract. Rubrospinal tract. Trigeminal laminiscus . Spinal lamniscus . Medial longitudinal fasciculus . Central tegmental tract

17. Cuneocerebellar Tract

18. Spinoolivary tract

19. Ant. & post External arcuate fibre

20. Striamedularis or arcuatocerebellar tract

21. Rubrospinal tract

22. Rubrospinal tract

23. Trigeminal laminiscus

24. Spinal laminiscus

25. Medial longitudinal fasciculus

26. Central tegmental tract

27. Central tegmental tract

28. Gray matter Spinal nucleus of acessory nerve. Nucleus gracilis nucleus cuneatus . Nucleus of spinal tract of trigeminal nerve. Accessory cuneate nucleus. Inferior olivary nucleus. Medial and dorsal accessory olivary nuclei Hypoglossal nucleus. Dorsal nucleus of vagus. Nucleus of tracts solitaries. Inferior and medial vestibular nuclei . Dorsal and ventral cochlear nuclei. Nucleus ambiguous. Arcuate nuclei.