Sleep-Onset Insomnia
By Liji Thomas, MD
Insomnia is the inability to initiate or maintain sleep, or to experience restful or high-quality sleep. It is considered to affect about a third of the population. Different types have been identified depending on the phase of sleep in which difficulty is reported. Thus, sleep-onset insomnia, middle-of-the-night (MOTN) insomnia, or early-morning awakenings are all reported.
When insomnia symptoms last for less than three months, it is termed short-term insomnia, while long-term insomnia lasts longer than this period.
http://www.news-medical.net/health/Sleep-Onset-Insomnia.aspx
