According to the investigation, who is likely to have nightmares?

Psychologists have confirmed what writers have always believed: that books are literally the stuff of dreams. A survey has confirmed that people with a taste for fiction experienced dreams that contained more improbable events, and their dreams were more emotionally intense. The survey also found that people who read thrillers were no more likely to have nightmares. But those with a weakness for science fiction were rather more likely to wake up suddenly with a cold sweat. The study, according to Mark Blagrove of the University of Wales, is perhaps the first experiment to determine a link between the waking world and dreams. Dr. Blagrove and colleagues distributed 100,000 questionnaires about sleep patterns and literary taste, and got more than 10,000 replies. They found that 58% of all adults had experienced at least one dream in which they were aware they were dreaming -- and that women could recall more dreams than men. Older people seemed to dream less and have fewer nightmares. Around 44% of children said their dreams were affected by the books they had been reading. "Children who report reading scary books have three times the number of nightmares as children who don’t," said Dr. Blagrove.