Anatomy and Physiology of Brain-stem.

1. CREATED BY
FOWZUL FAHAD

4.  The brainstem (or brain stem) is the
posterior part of the brain, adjoining and
structurally continuous with the spinal
cord. It is composed of the midbrain and
portions of the hindbrain. Specifically the
pons and medulla oblongata is the part of
hindbrain.

5.  In vertebrate anatomy, the brainstem is the
most inferior portion of the brain, adjoining
and structurally continuous with the brain
and spinal cord. The brainstem gives rise to
cranial nerves 3 through 12 and provides
the main motor and sensory innervations to
the face and neck via the cranial nerves.

8. It Consists of
 The midbrain,
 Pons &
 Medulla oblongata.
Here,
 3 and 4 – midbrain
 5-pons
 6,7,8 - junction of pons and
medulla.
 9,10,11,12 – medulla
oblongata.

9.  The midbrain is the area of
the brain situated around
the cerebral aqueduct
between the cerebrum
above and the pons below.
 It consists of nuclei and
nerve fibers (tracts) which
connect the cerebrum with
lower part of the brain and
with spinal cord.

10. Associated with vision
Hearing
Motor control
Sleep & wake cycle
Alertness
Temperature regulation

11.  The pons is situated in front of the cerebellum,
below the midbrain and above the medulla
oblongata.
 It consists mainly nerve fibers (white matter)
that from a bridge between two hemispheres of
the cerebellum. There are nuclei within the pons
that act as relay stations and some these are
associated with the cranial nerves.

12.  Contains nuclei that relay signals from the forebrain to
the cerebellum.
 Along with nuclei that deal primarily with sleep.
 Respiration
 Swallowing
 Bladder control
 Equilibrium
 Taste
 Eye movement
 Facial expression
 Facial sensation
 posture

13.  The medulla oblongata is the most interior region of the
brain. Extending from the pons above, it is continuous with
the spinal cord below. It is about 2.5 cm long.
 Its anterior and posterior surfaces are marked by central
fissures. The outer aspect is composed of white matter, gray
matter. Some cells constitute relay station for sensory nerves
passing from spinal cord to the cerebrum.
 The vital centres, consisting of groups of cell bodies (nuclei)
associated with autonomic reflex activity, lie in its deeper.
These are,
1. Cardiovascular centre
2. Respiratory centre
3. Reflex centres

14. The lower half of the brainstem that
contains the cardiac.
Involuntary functions such as breathing.
Respiratory.
Vomiting.
Vasomotor centers and regulates
autonomic.
Heart rate, and blood pressure.

15. Abnormalities in cranial nerve function.
 Leading to visual and hearing disturbances
 Changes in sensation
 Muscle weakness
Vertigo
Co-ordination problems
Swallowing and speech difficulty
voice changes.