[Etiology of adult insomnia].

In the article, the author develops an analysis of external and intrapsychic factors related to adults' insomnia. First she undertakes a literature review to describe semiological, evolutive and etiological levels of insomnia. From a semiological point of view, it is usual to differenciate initial insomnia (associated to the first phase of sleeping), intermittent insomnia (related to frequent awakenings) and final insomnia (related to early morning awakenings).