1. The brain stem is responsible for many basic functions. It takes in information from several senses through sensory regions for vision, hearing, taste, balance and touch in the facial area. It controls involuntary activity of the tongue, the larynx, the eyes, and the facial muscles through specific motor neurons for these areas. It controls levels of sleep and arousal through the reticular formation, nestled within its central core, and it co-ordinates the motor neurons in the spinal cord that control such activities as walking, breathing, and the beating of our hearts.