What are nightmares and sleepwalking examples of?

Nightmares and sleepwalking are both examples of parasomnias, which are abnormal behaviors or experiences that occur during sleep. Nightmares involve vivid and disturbing dreams that can cause distress and awaken the sleeper, while sleepwalking entails performing complex behaviors while still asleep, often without any memory of the event upon waking. Both phenomena highlight the complexities of sleep and the brain's activity during different sleep stages.