En español
NIDA

Menu

Grades 2-3

Background

In module 2, students will be asked to identify and learn about four parts of the brain: the cerebral cortex, composed of the right hemisphere and the left hemisphere; the cerebellum; the brain stem; and the limbic system. These parts are explained in more detail below.

Cerebral CortexCerebral Cortex

The brain’s largest part, the cerebral cortex, makes up almost 90 percent of the brain. It has two hemispheres. The left hemisphere, which controls the right side of the body, is largely responsible for analytical thinking, such as solving problems and comparing information needed to make decisions. It also is the brain’s language center.

The right hemisphere, which controls the left side of the body, is largely responsible for artistic expression and understanding relationships in space. A bundle of fibers called the corpus callosum serves as a bridge to pass messages back and forth between the two hemispheres.

CerebellumCerebellum

The cerebellum controls posture, movement, and the sense of balance. Such activities as playing ball, picking up objects, and playing musical instruments fall under its domain.

Brain StemBrain Stem

The brain’s most primitive part is the brain stem. The two main parts of the brain stem are the pons and the medulla. The pons contains fibers that link the cerebral cortex with the cerebellum and the spinal cord. It also controls sleep, awakening, and dream impulses.

The medulla controls heart rate, respiration, and blood pressure. The brain stem also is responsible for body temperature control, simple reflexes (like coughing and sneezing), and digestion.

Limbic SystemLimbic System

The two main parts of the limbic system are the hippocampus and the amygdala. The hippocampus is mainly responsible for learning and memory. The amygdala plays an important role in emotional behavior. The limbic system is greatly affected by drugs.

This page was last updated September 2012