The brain uses a variety of chemicals called neurotransmitters to communicate between brain cells.

To be able to see anything, eyes first need to process light. Vision begins with light passing through the cornea.

Researchers throughout the world are pursuing a variety of new ways to repair or replace neurons and other cells in the brain. For the most part, these experimental approaches are still being worked out in animals and cannot be considered therapies for humans at this time.

Insulation covering wires preserves the strength of the electrical signals that travel through them. The myelin sheath covering axons serves a similar purpose.

Optical imaging relies on shining weak lasers through the skull to visualize brain activity. These techniques are inexpensive and relatively portable. They are also silent and safe: Because only extremely weak lasers are used, these methods can be used to study everyone, even infants.

The ability to react quickly in response to threatening events has been with us since the time of our earliest ancestors.

Providing a high-quality, three-dimensional image of organs and structures inside the body without X-rays or other radiation, MRIs are noninvasive and unsurpassed in the anatomical detail they show.

Sleep is crucial for concentration, memory, coordination, and even emotional health. Research holds promise for devising new treatments to allow millions of people to get a good night’s sleep.

The brain uses some unconventional means to communicate.

The two halves of the nervous system work together in order for your body to properly communicate its sensations and needs.