Sleep is a biological need that helps us in relaxing the body and its muscles, in preserving energy and in consolidating the mnemonic information we acquire during the day. Despite the fact that these processes seem well known, the real “function” of sleep is still controversial. It is well known that we spend one third of our lives resting (approximately 8 hours per day) and, even intuitively, it can be understood that this function is crucial for our lives. Sleeping disorders, in fact, lead to psychological fatigue but also to impairments in decision-making and problem-solving processes. These cognitive processes have been connected, thanks to several neuroscientific researches, to the functions of the frontal lobes (the anterior part of the brain cortex, which is evolutionally recent) and it is interesting to notice that insomnia, one of the most severe sleeping disorders, is connected to dysfunctions in prefrontal brain areas1.
 Insomnia is characterized by the presence of waking states during the period that should be dedicated to sleep. It can involve the process of falling asleep (that is the inability of falling asleep), nocturnal awakenings (that is the inability of maintaining the sleeping state for the entire night, because of several continuous awakenings), and anticipated awakenings (the early interruption of the sleeping state and the impossibility of falling asleep again once awake). Usually, the quality of sleep is measured by analyzing different variables: on the one hand subjective elements are considered, for instance, patients are asked how good their sleep has been, and on the other hand objective variables, such as the duration of sleep episodes and the latency before falling asleep, are investigated. The study of hypnosis applied to sleep isn’t recent, in fact many studies1,2 confirmed that hypnotherapy and self hypnosis can lead to improvements in the treatment of sleeping disorders. Such improvements are obtained thanks to a cognitive modulation that reduces the hyper-activity of subjects who suffer from insomnia, and to a behavioural modulation aimed to a kind of muscular relaxation that is more suitable to sleeping states. Additionally an improvement in patients affected by post-traumatic stress disorder3 and in adolescents with family history ofdiabetes has been recently demonstrated. In the first study3, 17 patients were treated with hypnotherapy two times a week (1.5 hours per session) for two weeks and the effects of the treatment have been compared with a group of 15 subjects treated pharmacologically. Results showed that:
1) in both groups patients increased sleeping time between the first and the second session,
2) the hypnosis group showed a significant increase in sleep quality,
3) in both groups early awakenings became less frequent, but the reduction was greater in the group that received treatment with hypnosis.
Globally the research demonstrates that several variables, both objective and subjective, can be modified with hypnotic techniques.
In the second study4, 14 girls suffering from insomnia have improved the quality of sleep thanks to a combination of the cognitive-behavioral approach and hypnotic techniques. Furthermore, it has been reported that hypnotherapy has been well accepted and has favored the cognitive-behavioral intervention in the treatment of insomnia.
The above-cited studies show how hypnosis can be an important aid for those who suffer from sleep disorders, especially when integrated to a classical psychological therapy. This kind of effect, probably comes from the influence of hypnotic suggestions on frontal brain areas6 which are also involved in sleep disorders. In conclusion, we would like to recall the ancient etymology of the word hypnosis: from Hypnos (“Ὕπνος”), the god of sleep in Greek mythology.
[1] Thomas MSing HBelenky GHolcomb HMayberg HDannals RWagner HThorne DPopp KRowland LWelsh ABalwinski SRedmond D. Neural basis of alertness and cognitive performance impairments during sleepiness. I. Effects of 24 h of sleep deprivation on waking human regional brain activity. J Sleep Res. 2000, 9, 335-52.
[2] Paterson DC. Hypnosis: an alternative approach to insomnia. Can Fam Physician, 1982, 28, 768-770.
[3] Beng-Yeong Ng, Tih-Shih Lee. Hypnotherapy for sleep disorders. Ann Acad Med Singapore 2008, 37, 683-8.
[4] Abramowitz EG, Barak Y, Ben-Avi I, Knobler HY. Hypnotherapy in the treatment of chronic combat-related PTSD patients suffering from insomnia: a randomized, zolpidem-controlled clinical trial. Hntl J Clin Exp Hypnosis, 2008, 54, 270-280.
[5] Perfect MM, Elkins GR. cognitive–behavioral therapy and hypnotic relaxation to treat sleep problems in an adolescent with diabetes. J Clin Psychol, 2010, 66, 1205-1215.
[6] Halligan PWAthwal BSOakley DAFrackowiak RS. Imaging hypnotic paralysis: implications for conversion hysteria. Lancet, 2000, 355, 986-7.