Staying up late? You’re going Crazy
All night cram sessions, anyone in college has probably had more than just a few of these [okay maybe only if you are a procrastinator like me]. If you have done anything like that, well then you know how weird you start to feel. Well researchers have now shown that with a “mere” twenty-four hours of sleep deprivation can lead to conditions in healthy persons similar to the symptoms of schizophrenia. The team points out that this effect should be investigated more closely in persons who have to work at night [as anyone who works nights knows how hard that can be on a sleep schedule]. They also recommend that sleep deprivation may serve as a model system for the development of drugs to treat psychosis.
So what exactly is psychosis, there is a loss of contact with reality and this is associated with hallucinations and delusions [sound a little familiar?]. The chronic form is referred to as schizophrenia, which likewise involves thought disorders and misperceptions. The affected person may report that they hear voices, for example. Psychoses rank among the most severe mental illnesses [along as some of the most sad since a person will visually appear normal and healthy]. An international team of researchers has now found out that after 24 hours of sleep deprivation in healthy patients, numerous symptoms were noted which are otherwise typically attributed to psychosis or schizophrenia.
“It was clear to us that a sleepless night leads to impairment in the ability to concentrate,” says Prof. Dr. Ulrich Ettinger of the Cognitive Psychology Unit in the Department of Psychology at the University of Bonn. “But we were surprised at how pronounced and how wide the spectrum of schizophrenia-like symptoms was.”
The scientists examined a total of 24 healthy subjects [I know only 24] of both genders aged 18 to 40 in the sleep laboratory of the Department of Psychology. In an initial run, the test subjects were to sleep normally in the laboratory. About one week later, they were kept awake all night with movies, conversation, games and brief walks. On the following morning, subjects were each asked about their thoughts and feelings. In addition, subjects underwent a measurement known as prepulse inhibition.
[Loony hint: Prepulse inhibition is a standard test to measure the filtering function of the brain. Typically in these types of tests a light initial stimulus will then be followed by a stronger stimulus. This could be a noise for example, a soft one then a loud one. Normally a person will respond when a loud noise is played, but in certain cases a lighter pre-stimulus — or light noise– will cause a person to not respond to the loud noise.]
In the experiment, a loud noise is heard via headphones. As a result, the test subjects experience a startle response, which is recorded with electrodes through the contraction of facial muscles. If a weaker stimulus is emitted beforehand as a “prepulse”, the startle response is lower.
“The prepulse inhibition demonstrates an important function of the brain: Filters separate what is important from what is not important and prevent sensory overload,” says Dr. Petrovsky.
In the subjects, this filtering function of the brain was significantly reduced following a sleepless night. There were pronounced attention deficits, such as what typically occurs in the case of schizophrenia. They showed that following sleep deprivation, the subjects also indicated in questionnaires that they were somewhat more sensitive to light, color or brightness. Accordingly, their sense of time and sense of smell were altered and mental leaps were reported. Many of those who spent the night even had the impression of being able to read thoughts or notice altered body perception.
“We did not expect that the symptoms could be so pronounced after one night spent awake,” says the psychologist from the University of Bonn.
The scientists see an important potential application for their results in research for drugs to treat psychoses. In drug development, mental disorders like these have been simulated to date in experiments using certain active substances. However, these convey the symptoms of psychoses in only a very limited manner. Sleep deprivation may be a much better model system because the subjective symptoms and the objectively measured filter disorder are far more akin to mental illnesses. Of course, the the researchers suggest that the sleep deprivation model is not harmful: After a good night’s recovery sleep, the symptoms disappear.
So for anyone who has ever been, or is currently in college, we can all breathe a sigh of relief knowing we arent all going crazy [well too late for me obviously]. Want to stay up all night and read? You probably want the full study,which you can find —here!
Phillips, K., Bartsch, U., McCarthy, A., Edgar, D., Tricklebank, M., Wafford, K., & Jones, M. (2012). Decoupling of Sleep-Dependent Cortical and Hippocampal Interactions in a Neurodevelopmental Model of Schizophrenia Neuron, 76 (3), 526-533 DOI: 10.1016/j.neuron.2012.09.016