Deep sleep promotes our well-being, improves our memory and strengthens the body’s defences. Zurich and Fribourg researchers demonstrate how restorative SWS can also be increased without medication – using hypnosis.
Sleeping well is a crucial factor contributing to our physical and mental restoration. SWS in particular has a positive impact for instance on memory and the functioning of the immune system. During periods of SWS, growth hormones are secreted, cell repair is promoted and the defence system is stimulated. If you feel sick or have had a hard working day, you often simply want to get some good, deep sleep. A wish that you can’t influence through your own will – so the widely held preconception.
Sleep researchers from the Universities of Zurich and Fribourg now prove the opposite. In a study that has now been published in the scientific journal “Sleep”, they have demonstrated that hypnosis has a positive impact on the quality of sleep, to a surprising extent. “It opens up new, promising opportunities for improving the quality of sleep without drugs”, says biopsychologist Björn Rasch who heads the study at the Psychological Institute of the University of Zurich in conjunction with the “Sleep and Learning” project (see box).
Brain waves – an indicator of sleep quality
Hypnosis is a method that can influence processes which are very difficult to control voluntarily. Patients with sleep disturbances can indeed be successfully treated with hypnotherapy. However, up to now it hadn’t been proven that this can lead to an objectively measurable change in sleep. To objectively measure sleep, electrical brain activity is recorded using an electroencephalogram (EEG). The characteristic feature of slow-wave sleep, which is deemed to have high restorative capacity, is a very even and slow oscillation in electrical brain activity.
70 healthy young women took part in the UZH study. They came to the sleep laboratory for a 90-minute midday nap. Before falling asleep they listened to a special 13-minute slow-wave sleep hypnosis tape over loudspeakers, developed by hypnotherapist Professor Angelika Schlarb, a sleep specialist, or to a neutral spoken text. At the beginning of the experiment the subjects were divided into highly suggestible and low suggestible groups using a standard procedure (Harvard Group Scale of Hypnotic Susceptibility). Around half of the population is moderately suggestible. With this method women achieve on average higher values for hypnotic susceptibility than men. Nevertheless, the researchers expect the same positive effects on sleep for highly suggestible men.
Slow-wave sleep increased by 80 percent
In their study, sleep researchers Maren Cordi and Björn Rasch were able to prove that highly suggestible women experienced 80 percent more slow-wave sleep after listening to the hypnosis tape compared with sleep after listening to the neutral text. In parallel, time spent awake was reduced by around one-third. In contrast to highly suggestible women, low suggestible female participants did not benefit as much from hypnosis. With additional control experiments the psychologists confirmed that the beneficial impact of hypnosis on slow-wave sleep could be attributed to the hypnotic suggestion to “sleep deeper” and could not be reduced to mere expectancy effects.
According to psychologist Maren Cordi “the results may be of major importance for patients with sleep problems and for older adults. In contrast to many sleep-inducing drugs, hypnosis has no adverse side effects”. Basically, everyone who responds to hypnosis could benefit from improved sleep through hypnosis.
Maren Cordi, Angelika Schlarb, Björn Rasch. Deepening sleep by hypnotic suggestions. Sleep. 37(6). June 1, 2014. http://dx.doi.org/10.5665/sleep.3778
Sleep and Learning
The project “Sleep and Learning” is headed by Professor Björn Rasch from the University of Fribourg and conducted at the Universities of Zurich and Fribourg. The project is financed by the Swiss National Fund and the University of Zurich (main area of clinical research “Sleep and Health”). The goal of the project is to identify psychological and neurophysiological mechanisms underlying the positive role of sleep for our memory and mental health.
Bettina Jakob | Universität Zürich
Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
What does congenital Zika syndrome look like?
24.03.2017 | University of California - San Diego
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy