A nightmare is a terrifying dream, often of an encounter with a being (supernatural, human, or animal) of great strength and energy. A victim may have a feeling or great pressure on the chest, difficulty breathing, and a sense of powerlessness to move or speak. As soon as he is able to move, the victim may experience strong palpitations and a rise in blood pressure, a feeling of languor and listlessness as though physically and emotionally exhausted, and an indescribable depression, uneasiness and anxiety, all experienced with the impression that he has had a real encounter with terror.
Nightmares are most common in the early morning. They are normal on occasion, especially after frightening movies/TV shows or emotional situations. If recurrent, nightmares and night terror may be associated with psychological disturbances or severe stress, especially in adults.
A 1992 US study estimates 5-15% of people suffer from powerful recurrent nightmares.
Eating carbohydrates, such as pasta, less than four hours before sleep can increase the chances of a nightmare by 50 percent.