【参考范文】 This article introduced types and characteristics of insomnia as well as diagnostic assessment. Insomnia is considered as a subjective condition of insufficient or non-restorative sleep despite an adequate opportunity to sleep, which accounts for 30% to 40% in the general adult population. The Association for the Psycho-physiological Study of Sleep has classified insomnia as 6 types. 1.Psycho-physiologic insomnia which covers the transient and short-term problems associated with situational factors. 2.Psychiatric insomnia always has a very high concordance with depression, other affective disorders and psychosis. 3. Insomnia can be also cause by alcohol and the use of central nervous system stimulants. 4. The patients who suffered from sleep-induced respiratory problems usually have multiple arousals and awakening during the night. 5. Some patients would be affected by the environmental causes. 6. The last one is unknown causes. Insomnia cannot be diagnosed by the amount of time a person sleeps. Rather, it is distinguished by the daytime consequences of unsatisfactory sleep. A pertinent history for insomnia would include
