The brain is the part of the central nervous system within the cranial cavity. It is the control centre for registering sensations, correlating them with one another as well as stored information, making decisions, and taking actions.

The brain consists of four major parts, the brain stem, cerebellum, diencephalon, and cerebrum.

In this interactive you will learn more about the location, structure and function of each of these parts of the brain.

Location

Between the spinal cord and the diencephalon.

Structure

Consists of three structures: medulla oblongata, pons, and midbrain. Contains all of the sensory (ascending) tracts and motor (descending) tracts that extend between the spinal cord and other parts of the body.

Functions

Regulates vital body functions including heart rate, blood pressure and breathing. Damage to this area of the brain can cause death.

Location

Most inferior portion of brain stem.

Structure

Is continuous with the spinal cord.

Functions

Regulates heartbeat, blood vessel dilation, breathing, swallowing, vomiting, coughing, sneezing, balance and coordination.

Location

Between the spinal cord and the diencephalon.

Structure

The term ‘pons’ means bridge, because a function of the pons is to connect the cerebrum and cerebellum.

Functions

Controls breathing, swallowing and balance (with the medulla), as well as chewing and salivation.

Location

Most superior portion, and smallest part, of brain stem.

Structure

The anterior part of the midbrain contains paired bundles of axons called cerebral peduncles, whilst the posterior part contains four rounded elevations called colliculi.

The midbrain also contains two other clusters of nerve cell bodies called the substantia nigra and the red nucleus.

Functions

Colliculi coordinate movements of the head, eyes, and trunk in response to auditory stimuli (sounds).

The substantia nigra and the red nucleus regulate general body movements.

Location

Attached to the posterior brain stem. Occupies the inferior and posterior aspect of cranial cavity.

Structure

The term ‘cerebellum’ means little brain, because the cerebellum resembles a smaller version of the main part of the brain (the cerebrum). Highly folded surface that greatly increases it surface area for neurons.

Functions

Regulates posture and balance.

Location

Between the brain stem and the cerebrum.

Structure

Includes three main components, the: thalamus (80% of the diencephalon), hypothalamus and epithalamus.

Functions

The thalamus relays all sensory information (except smell) to the cerebrum, controls some skeletal muscles, and maintains consciousness.

The hypothalamus controls and integrates activities of the autonomic nervous system, endocrine system (i.e. hormones), limbic system (i.e. mood, emotion, motivation) and basic body functions including body temperature, thirst, hunger and sexual arousal.

The epithalamus secretes melatonin which promotes sleepiness, and is involved in the emotional response to smell.

Location

The cerebrum is the largest part of the brain.

Structure

The cerebrum is divided into left and right hemispheres by a longitudinal fissure. On the surface of the cerebrum are numerous folds called gyri separated by grooves called sulci. Each cerebral hemisphere is divided into frontal, parietal, temporal and occipital lobes.

Functions

The frontal lobe initiates voluntary motor functions, aggression, smell and mood. The parietal lobe receives and evaluates most sensory information. The temporal lobe receives and evaluates input for smell and hearing, and plays an important role in memory, thought and judgement. The occipital lobe receives and integrates visual information.