In medicine, the ways in which the body receives signals from the environment. The five human senses are sight, hearing, smell, taste, and touch. The body receives signals through the sense organs (the eyes, ears, nose, tongue, and skin). These organs have special nerves that send signals to the brain. The brain processes these signals and then sends information back to the rest of the body to tell it how to respond to the signal. Aging, certain diseases or conditions, and some types of medicines or treatments can affect the senses.