The document outlines the three layers of the brain: The brain stem contains 7 main parts including the medulla, pons, and cerebellum that regulate basic functions like breathing and movement coordination. The limbic system's hippocampus, amygdala, and hypothalamus are responsible for memory, emotion, and regulating body temperature and fluids. The cerebral cortex's four lobes - frontal, parietal, temporal, and occipital - control thinking, touch sensation, auditory processing, and visual information, respectively.