The structure that connects the brain to the spinal cord is known as the brainstem. The brainstem comprises three main parts: the midbrain, pons, and medulla oblongata. It plays a crucial role in regulating vital functions such as breathing, heart rate, and blood pressure. Additionally, the brainstem is responsible for relaying information between the brain and the body, facilitating communication for motor and sensory pathways. Given its central role in many automatic functions and its influence on the nervous system, the brainstem is essential for maintaining homeostasis and overall bodily function.