You can watch the video on my you tube channel: https://youtu.be/I0FaX-iQfa0 Medulla oblongata or more simply medulla is part of brain stem which forms base of the brain stem. It contains pyramid, olive and above pyramidal structure, there is decussation of pyramids which explains why each part of brain controls opposite part of body. Adding to that medulla also has several nuclei which controls activity of cardiovascular system and respiratory system. Medulla also has nuclei for controlling reflexes of vomiting, swallowing, hiccuping, coughing and sneezing. It has also nuclei for test, hearing and balance. Medulla also contains nuclei of cranial nerve number VIII, IX, X, XI and XII.

2. The brain stem is the part of the brain between the spinal
cord and the diencephalon.
It consists of three structures:
(1) Medulla oblongata,
(2) Pons, and
(3) Midbrain.
Extending through the brain stem is the reticular formation,
a net like region of interspersed gray and white matter.

5. Medulla Oblongata

6. The medulla oblongata, or more simply the medulla, is
continuous with the superior part of the spinal cord; it forms
the inferior part of the brain stem.
The medulla begins at the foramen magnum and extends to the
inferior border of the pons, a distance of about 3 cm (1.2 in.).

7. The medulla’s white matter contains all sensory (ascending) tracts and
motor (descending) tracts that extend between the spinal cord and
other parts of the brain.
Some of the white matter forms bulges (knobs) on the anterior
aspect of the medulla.
These knobs, called the pyramids are formed by the large
corticospinal tracts that pass from the cerebrum to the spinal
cord.
The corticospinal tracts control voluntary movements of the
limbs and trunk.

9. Just superior to the junction of
the medulla with the spinal cord,
90% of the axons in the left
pyramid cross to the right side,
and 90% of the axons in the right
pyramid cross to the left side.
This crossing is called the
decussation of pyramids and
explains why each side of the
brain controls voluntary
movements on the opposite side
of the body.

10. Just lateral to each pyramid is an oval-shaped swelling called an
olive.
Within the olive is the inferior olivary nucleus, which receives input
from the cerebral cortex, red nucleus of the midbrain, and spinal
cord.
Neurons of the inferior olivary nucleus extend their axons into the
cerebellum, where they regulate the activity of cerebellar neurons.
By influencing cerebellar neuron activity, the inferior olivary
nucleus provides instructions that the cerebellum uses to make
adjustments to muscle activity as you learn new motor skills.

13. The medulla also contains several nuclei. (Recall that a nucleus
is a collection of neuronal cell bodies within the CNS.)
Some of these nuclei control vital body functions. Examples of
nuclei in the medulla that regulate vital activities include the
Cardiovascular center and
The medullary rhythmicity area.
The cardiovascular center regulates the rate and force of the
heartbeat and the diameter of blood vessels.
The medullary rhythmicity area of the respiratory center
adjusts the basic rhythm of breathing.

14. Nuclei for vital functions
Cardiovascular center regulates
the rate and force of the
heartbeat and the diameter of
blood vessels.
The medullary rhythmicity
area of the respiratory
center adjusts the basic
rhythm of breathing.

15. Besides regulating vitals, nuclei in the medulla also control
reflexes for
Vomiting
Swallowing
Sneezing
Coughing and
Hiccupping

16. Stimulation of vomiting center of the medulla
causes vomiting, the forcible expulsion of the
contents of the upper gastrointestinal (GI) tract
through the mouth.
The deglutition center of the medulla promotes
swallowing of a mass of food that has moved
from the oral cavity of the mouth into the
pharynx (throat).
Sneezing involves spasmodic contraction of
breathing muscles that forcefully expel air
through the nose and mouth.

17. Coughing involves a long pinched and deep
inhalation and then a strong exhalation that
suddenly sends a blast of air through the upper
respiratory passages.
Hiccupping is caused by spasmodic contractions
of the diaphragm (a muscle of breathing) that
ultimately result in the production of a sharp
sound on inhalation.

18. Nuclei associated with sensations of touch, pressure, vibration,
and proprioception (conscious awareness of position) are
located in the posterior part of the medulla.
These nuclei are the right and left gracile nucleus and cuneate
nucleus.

20. The medulla also contains nuclei that are components of sensory
pathways for gustation (taste), audition (hearing), and
equilibrium (balance).
The gustatory nucleus of the medulla is part of the
gustatory pathway from the tongue to the brain; it
receives gustatory input from the taste buds of the
tongue.
The cochlear nuclei of the medulla are part of the
auditory pathway from the inner ear to the brain;
they receive auditory input from the cochlea of
the inner ear.

21. The vestibular nuclei of the medulla and
pons are components of the equilibrium
pathway from the inner ear to the brain; they
receive sensory information associated with
equilibrium from proprioceptors in the
vestibular apparatus of the inner ear.

22. Finally, the medulla contains nuclei associated with five pairs of
cranial nerves :
Vestibulocochlear (VIII) nerves,
Glossopharyngeal (IX) nerves,
Vagus (X) nerves,
Accessory (XI) nerves (cranial portion), and
Hypoglossal (XII) nerves.

25. The brain stem is the
part of the brain
between the spinal
cord and the
diencephalon.
It consists of three
structures:
(1) Medulla
oblongata,
(2) Pons, and
(3) Midbrain.

26. Location of medulla oblongata: superior to the spinal cord;
inferior to the pons, 3 cm Long.

27. Anterior aspect of the medulla:
Known as the pyramids,
Formed by the large corticospinal tracts.
Function: Control voluntary movements of the limbs and trunk

28. Decussation of pyramids: A cross over of neurons, Superior to
the junction of the medulla with the spinal cord.
It explains why each side of the brain controls voluntary
movements on the opposite side of the body.

29. Olive: Oval-shaped swelling, just lateral to each pyramid.
Within the olive is the inferior olivary nucleus, receiving
input from the cerebral cortex, red nucleus of the midbrain, and
spinal cord.
Neurons of the inferior olivary nucleus regulate the activity
of cerebellar neurons by providing instructions, that the cerebellum
uses to make adjustments to muscle activity as you learn new motor
skills.

30. Nuclei for vital functions
Cardiovascular center regulates
the rate and force of the
heartbeat and the diameter of
blood vessels.
The medullary rhythmicity
area of the respiratory
center adjusts the basic
rhythm of breathing.

32. Gracile and cuneate nucleus: Located in the posterior part of
the medulla, associated with sensations of touch, pressure,
vibration, and conscious awareness of position.

33. • Gustatory pathway from the tongue to the brain; it
receives gustatory input from the taste buds of the
tongueGustation (taste)
• Auditory pathway from the inner ear to the brain;
they receive auditory input from the cochlea of the
inner ear
Audition
(hearing)
• Equilibrium pathway from the inner ear to the
brain; they receive sensory information
associated with equilibrium from proprioceptors
in the vestibular apparatus of the inner ear
Equilibrium
(balance)