75 Key Terms Key Terms delayed sleep phase syndrome (DSPS) condition that results from a delay in the sleep-wake cycle that affects a person’s daily activities insomnia trouble falling or staying asleep parasomnia term for sleep disorders that occur when people are partially, but not completely, awoken from sleep sleep apnea potentially serious disorder in which a person stops breathing for short periods of time during sleep narcolepsy disorder that affects the brain’s ability to control the sleep-wake cycle 3.2Lesson Learning Outcomes After studying this lesson, you will be able to • explain symptoms of delayed sleep phase syndrome and insomnia. • describe common types of parasomnia. • understand the symptoms of and treatment for sleep apnea. • explain the symptoms of narcolepsy. Common Sleeping Problems Graphic Organizer Graphic Organizer Sleep Disorders In a table like the one shown below, list all the sleep disorders you know about and include a list of possible causes for each one. If multiple disorders have possible causes in common, highlight each repeated cause in a different color. Zurijeta/Shutterstock.com Zurijeta/ Shutterstock co Sleep Disorders Possible Causes