Morning erections occur during REM sleep when penis engorges with blood. Testosterone levels tend to be higher in the morning. Physical touch from bedsheet can trigger erections. Full bladder pressing on sacral nerve can cause morning erections
Everyone dreams every night for about two hours. Most dreams last 5-20 minutes and are forgotten within minutes. People spend an average of six years dreaming during their lifetime
Nightmares are common in children, especially preschoolers aged 3-6. Most people have experienced nightmares, but adults have less frequent ones. Nightmares occur during REM sleep, most frequently during second half of night
Nightmares are disturbing dreams that awaken people with negative feelings. Nightmares are common in children but can occur at any age. Girls tend to have nightmares more often than boys in teens. Nightmare disorder is rare but occurs when nightmares are frequent and distressing
Dreams occur during REM sleep, lasting 5-20 minutes. Everyone has 3-6 dreams per night, forgetting 95% upon waking. Dreams help clear memories and process information
Dreams are mini-movies created during sleep lasting 2-20 minutes. Humans dream 4 times per night, most vivid during REM sleep. REM sleep activates brain waves similar to waking state. Different animals experience REM sleep but don't know they dream