Which are the four major divisions of the brain?

• A. Cerebrum, Diencephalon, Brain Stem, Cerebellum
• B. Cerebrum, Brain Stem, Spinal Cord, Cerebellum
• C. Cerebellum, Midbrain, Pons, Medulla
• D. Cortex, Thalamus, Hypothalamus, Pituitary

Answer: (A)

The brain is organized into four major divisions: the cerebrum, the diencephalon, the brain stem, and the cerebellum. The cerebrum is the largest part and handles conscious thought, sensation, voluntary movement, learning, and memory. The diencephalon sits between the cerebrum and brain stem and contains structures like the thalamus and hypothalamus, which act as relay centers and help regulate autonomic functions and the endocrine system. The brain stem connects the brain to the spinal cord and governs essential life-sustaining processes such as heart rate, breathing, and digestion, comprising the midbrain, pons, and medulla. The cerebellum sits at the back of the brain and coordinates movement, balance, and motor learning.

Spinal cord is not a division of the brain, and the other options mix components that aren’t four distinct brain divisions (for example, parts of the brain stem or regions within the cerebrum).