What is the primary symptom associated with nightmares?

The primary symptom associated with nightmares is the vivid recall of dream content. Nightmares are characterized by intense, disturbing dreams that often provoke strong negative emotions such as fear, anxiety, or helplessness. Individuals experiencing nightmares typically wake up during or shortly after the dream and are able to remember the details quite vividly, specifically the emotional impact and narrative of the dream. This vivid recall distinguishes nightmares from other sleep disturbances and is central to their diagnosis and understanding.

In contrast, other options refer to different sleep-related phenomena. Abrupt arousal with little memory is more characteristic of disorders like sleep terrors, where individuals wake suddenly but may not remember the details. Sensations that increase during inactivity might relate to other disorders like restless leg syndrome, and episodes of motor activity during sleep could refer to REM sleep behavior disorder, where individuals act out their dreams but do not experience the same vivid recall associated with nightmares.