APP 1B BRAIN STUFF

Brain stem

The most primitive of the brain's three major layers. It includes the medulla, pons, and reticular formation.

Medulla

A brain-stem structure that controls breathing and heart rate. The sensory and motor pathways connecting the brain to the body cross in this structure.

Pons

A brain-stem structure that regulates brain activity during sleep and dreaming.

Reticular formation

A pencil-shaped structure forming the core of the brain stem. This structure arouses the cortex to keep the brain alert and attentive to new stimulation.

Thalamus

The brain's central "relay station," situated just atop the brain stem. Nearly all messages going into or out of the brain go through this structure.

Cerebellum

The "little brain" attached to the brain stem. It is responsible for coordinated movements.

Limbic system

The middle layer of the brain, involved in emotion and memory. This includes the hippocampus, amygdala, hypothalamus, and other structures.

Hippocampus

A component of the limbic system, involved in establishing long-term memories.

Amygdala

A limbic system structure involved in memory and emotion, particularly fear and aggression.

Hypothalamus

A limbic structure that serves as the brain's blood-testing laboratory, constantly monitoring the blood to determine the condition of the body.

Cerebral cortex

The thin gray-matter covering of the cerebral hemispheres, consisting of a 1/4-inch layer dense with cell bodies of neurons. It carries on the major portion of our "higher" mental processing, including thinking and perceiving.

EEG

A device for recording brain waves, typically by electrodes placed on the scalp.

CT Scan

A computerized imaging technique that uses X rays passed through the brain at various angles and then combined into an image.

PET Scan

An imaging technique that relies on the detection of radioactive sugar consumed by active brain cells.

MRI

An imaging technique that relies on cells' responses in a high-intensity magnetic field.

fMRI

A type of MRI that reveals which parts of the brain are most active during various mental activities.