(PhysOrg.com) -- Almost everyone has nightmares at some time in their lives, while a few have nightmares almost every night, but no one is quite certain what they mean. Now scientists in Germany carrying out one of the largest ever studies on nightmares have found there are clear differences in the nightmares of men and women, and while the nightmares may not have a direct correspondence to the waking life they probably do reflect the sleeper's deepest concerns and emotions.
Nightmares usually occur during REM sleep, and are defined as disturbing mental experiences. They often cause the dreamer to awaken. The last few years have seen an increase in the number of publications about the frequency and psychopathology of nightmares, but there have been few systematic studies of the content of nightmares in adults.
The study, carried out by Dr Michael Schredl of the International Association for the Study of Dreams, involved over 2,000 people, who were asked to report on their bad dreams. The results were that 48% reported never experiencing nightmares, 10% said they had them a few times a year, and nearly 5% reported having frightening dreams at least every couple of weeks. The most common nightmare topics were falling, being late, paralyzed or chased, and losing loved ones.
The study found nightmares about being fired from a job, or about violence were more common in men, while for women nightmares of sexual harassment or a death of a loved one were more prevalent. Women were also more likely to have bad dreams about losing their hair or teeth, perhaps suggesting an anxiety about becoming unattractive. Both genders reported nightmares about failing exams, and they could have such dreams even if they were not students.
Dr Schredl said nightmares about being paralysed, falling, or being chased do not usually correspond directly to experiences in the dreamer’s waking life, but may reflect waking fears. For example, being chased by a monster in a dream might be a metaphor for a daytime fear of a task the dreamer would like to avoid. Dr Schredl said more research is needed to investigate the “possible metaphoric relationship” between nightmares and stressors in waking-life.
The results of the study are published in a paper in the European Archives of Psychiatry and Clinical Neuroscience journal.
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More information: Nightmare frequency and nightmare topics in a representative German sample, Michael Schredl, European Archives of Psychiatry and Clinical Neuroscience, DOI:10.1007/s00406-010-0112-3