This area of the brain is not only the oldest area, but also is located in the most inner regions of the brain. The brainstem is located just above the spinal column. In fact, it is located directly above the spinal column, and is where the spinal cord enters the brain. The brainstem includes the
medulla (responsible for functions such as respiration), and the reticular formation, which acts like a bridge; it allows information to pass back and forth from one side (hemisphere) of the brain to the other.