Answer: Nightmares have a more intense emotional impact.
Step-by-step explanation:
Nightmares are frightening dreams that might occur as a result of stress, anxiety, sleep disorder, or even post-traumatic stress disorder. During a nightmare, we experience emotions such as anger, guilt, sadness - which are all intense emotions. This explains why nightmares are more memorable than other, regular dreams. According to the estimates, 95% of all dreams are entirely forgotten immediately after awakening. However, as the nightmares are vivid, we do not forget them so easily.