The brain is the most important organ of the human body, responsible for regulating involuntary bodily functions, muscle movement, consciousness, memory and thought. It uses the most energy of any organ, and the body could not function without the brain. Science has yet to fully understand how the brain works.
The part of the brain responsible for involuntary bodily functions is the medulla oblongata, located at the base of the skull near the brain stem. It controls the heartbeat, breathing, digestion and other functions without conscious thought.
The cerebellum is responsible for muscle movement, balance and posture. It also is responsible for relaying procedural memory, also known as muscle memory. This includes learned skills, such as driving, riding a bicycle or shooting a basketball.
The cerebrum is responsible for processing sensory input, dealing with cognitive function and emotions as well as handling short- and long-term memory. It also controls logic and problem-solving.
It is a common myth that people only use 10 percent of available brain power. Actually, people use much more of their brains, but not all at once. The majority of brain activity consists of background processes that most people don't think about. With such an energy-hungry organ, it makes little evolutionary sense to have so little of it actually used. Most of the brain's systems work together constantly to process information about the world and react accordingly.