Anatomy and physiology

2.  Consists of:
 Midbrain
 Pons
 Medulla oblangata.
 Superiorly continuous with forebrain.
 Inferiorly continuous with spinal
cord.
 Posteriorly pons and medulla is
seperated by fourth ventricle.

3.  Midbrain, pons and medulla
connected to cerebellum by
superior,middle and inferior
cerebellar peduncle resp.

5.  3 and 4 – midbrain
 5-pons
 6,7,8-junction of pons and medulla.
 9,10,11,12-medulla

7.  The tissue in the floor of the
aqueduct,between the 3rd and 4th
ventricles of brain contains ARAS
(Ascending Reticular Activating System)
 ARAS: extends throughout the
brainstem from the spinal cord to the
subthalamus.
Determines arousal

8.  Damage to ARAS or areas of cerebral
hemisphers- disturbance of normal
conciousness.
 If this area is dead- Person will be
irreversibly unconcious and apnoeic.

9. CEREBRAL
PEDUNCLE
TECTUM
TEGMENTUM
SUBSTANTIA
NIGRA
CRUS CEREBRI

10.  lies between midbrain above and
medulla below in front of cerebellum.
 Include neural pathways that
conduct signals from brain down to
cerebellum and medulla and that
carry signals upto thalamus.
 Contains nuclei that deals with
respiration, swallowing, bladder
control, hearing,equilibrium, eye
movts. facial sensation, facial
expressions etc.

11.  Located in the hind brain anterior to
cerebellum.
 Contains cardiac , respiratory,
vomiting and vasomotor centers and
thus deals with breathing, heartrate,
blood pressure.

12.  A properly functioning paramedian
tegmental area of brainstem-precondition
for full consiousness.Enables cerebral
hemispheres to work in integrity.
 Responsible for respiratory drive.
 Maintenance of blood pressure.

13. All motor output travel through
the brainstem.
Vision,smell,all the sensory
traffic arrives through the
brainstem.
Mediates cranial nerve reflexes.