The posterior part of the brain is called the hindbrain. It consists of 3 parts. namely-
1. Cerebellum: Two equal hemispheres coiled under the cerebral hemispheres are called cerebellum. The hemispheres are connected by two vermis. It is the largest part of the hindbrain. Its outer part is made up of gray matter and the inner part is made up of white matter. Its average weight is about 150 grams.
Functions of the cerebellum
(i) It controls muscle tension of voluntary muscles.
(ii) Maintains body balance and posture.
(iii) It determines the direction of movement.
2. Pons: The thick band on the opposite side of the cerebellum is called the pons. It lies above the medulla oblongata.
Pons’ work
(i) It acts as a relay station between the nervous system and the brain.
(ii) It regulates the rate of respiration.
(iii) It coordinates muscle activity.
(iv) 5th-8th carotid nerves arising from the pons perform various functions of the body.
3. Medulla oblongata: The pyramidal shaped part located below the pons is called the medulla oblongata. Its length is about 3 cm, width 2 cm and thickness 1.2 cm.
Functions of the medulla oblongata
(i) It acts as a control center for respiration, digestion, constriction of blood vessels, secretion of saliva, heartbeat etc.
(ii) regulates blood pressure, defecation, alimentary canal peristalsis etc. (RRAR) Protects the connection between the brain and the nervous system.
(iii) It gives rise to the 9th, 10th and 11th carotid nerves and controls various functions.