Final answer:
The Reticular Activating System (RAS) is a diffuse region of gray matter throughout the brain stem that regulates sleep, wakefulness, and states of consciousness.
Step-by-step explanation:
The Reticular Activating System (RAS) is a diffuse region of gray matter throughout the brain stem that regulates sleep, wakefulness, and states of consciousness. It extends from the midbrain into the forebrain and hindbrain. The RAS is important in regulating the sleep/wake cycle, arousal, alertness, and motor activity.arn more about Reticular Activating System here: