The 13th Berlin Colloquium
of the Gottlieb Daimler and Karl Benz Foundation

Session
Conference (on) Sleep
Sleep Research - Results of a New Science °
Chairman: Prof. Thomas Penzel
Interdisciplinary Centre of Sleep Medicine, Charité Berlin

Evening Lecture
Learning and Working Asleep - Myth or Reality?
Ingo Fietze, MD
Interdisciplinary Centre of Sleep Medicine, Charité Berlin

May 27th 2009
Langenbeck-Virchow House, Berlin

Sleep - An Unsolved Mystery
and an Important Resource for Humanity

Report: Kristina Vaillant
Fotos: Matti Hillig and the foundation

Even after 70 years of sleep research, many questions remain unanswered in connection with the phenomenon of sleep. "Sleep is still one of science's greatest mysteries," said Professor Eckard Minx (President of the Board of the Gottlieb Daimler and Karl Benz Foundation), at the opening of the colloquium. With an allusion to the high costs of traffic- and other accidents which can be traced back to overtiredness as a cause, he made clear how important the study of sleep is. "We spend a third of our lives asleep; in comparison, five seconds of sleep are negligible. But at the steering wheel of an automobile or at other control instruments, this instant in time can decide over life or death."

A participant contributed another argument for the vital importance of sleep research: Sleep is one of humanity's most important health resources - like nutrition. In all, more than 170 participants came to the 13th Berlin Colloquium in the Charité's Langenbeck-Virchow House in Berlin. Physicians, occupational physiologists, association representatives, and members of self-help groups learned which results sleep researchers have obtained to the present from the psychological, medical, and neurological perspective, how these findings can help the afflicted and the healthy, and how they can contribute to traffic safety.

Why We Sleep

The sleep scientist and the colloquium's scientific director, Professor Thomas Penzel (Charité, Berlin), first gave an introduction into the scientific understanding of sleep by explaining sleep's various functions and the mechanisms of sleep regulation: Sleep is regulated by the interaction of the internal clock and by the building up of fatigue by day, resp., the decrease of fatigue by night. People sleep in order to refresh themselves physically and mentally, for a well-functioning memory, a functioning hormonic system, a functioning immune system. Further, sleep serves in general to provide resources for performance by day. How sleep regulation works on the level of the individual cell, has, however, not yet been studied in detail, he said, and pointed out how important basic research is: "We know which nerve cells are responsible for the regulation of the 24-hour rhythm, the internal clock, but which nerve cells regulate sleep?" In order to investigate this, one could, above all, make use of statistical-physical methods which, in the past years, have been refined in - of all disciplines - seismological research.

The Brain Asleep: Twilight State or Psychophysical Activity?

The fact that sleep, as a field of research as well as in connection with prevention of illness, is still a scientific wallflower, has, from the standpoint of the medical Professor Thorsten Schaefer (Ruhr University, Bochum), primarily to do with an image problem. Sleep's image problem in our achievement-oriented society is due to the fact that sleep gives the impression of inactivity, that people don't do anything when they're sleeping. But the neurologist and psychiatrist, Hans Berger, demonstrated as early as 1924, with the help of Electroencephalography (EEG), which he invented, that the brain doesn't descend into a twilight state in sleep. In sleep, as Schaefer said, energy expenditure isn't reduced, and further, a close relationship between sleep and learning has been proven. He demonstrated what can threaten when sleep is prevented on the example of an animal experiment: Rats, which had been deprived of sleep, died after two to three weeks.

"Sleep is activity, even if this isn't perceived consciously,"confirmed also the neurologist and psychiatrist Goeran Hajak (Psychiatric University Clinic Regensburg). The stages of sleep recorded by EEG in sleep laboratories are, for that reason, used by psychiatrists to make diagnoses. For example, waking out of dreaming sleep can indicate that the sleeper is confronted with distressing dream contents, and, for that reason, flees into waking. In this case, a psychotherapy would be the best method of restoring restful sleep. "Sleep", as Hajak said, "is the soul's seismograph." It brings the psychophysical functions into balance.

Sleep Disorders: Frequency and Treatment

Professor Claudio Bassetti (Neurocenter Svizzera Italiana, Lugano) came here from Switzerland, one of the traditional strongholds of sleep research. The physiologist Rudolf Hess in Zurich, as early as the 1920s - roughly parallel to Hans Berger's work in Jena -, had already discovered the sleep centre in the brain, and, against the then prevailing opinion that sleep be a functional deficiency, described the process of sleep as an active state. Bassetti listed in his lecture the various causes of sleep disturbances in detail - from organic, by way of psychic, to genetic and age-related causes. But sleep disorders are so common - insomnias (sleeplessness), for example, afflict 10-20% of the population - that these complaints are a subject that every family doctor has to concern himself with. He could then, in serious cases, refer a patient to a sleep specialist. Besides the frequency of sleep disorders, it is, above all, the consequences of a sleep disturbance which persevere for a longer period of time which make treatment urgent. Besides irritability and a lack of concentration, the risk of suffering a stroke or a heart attack, in particular, increases when sleep disturbances such as sleep apnea or the restless leg syndrome (RLS) are left untreated. Besides these, other diseases can also be diagnosed by observing sleep. For example, a depression manifests itself in characteristic sleep disturbances, the neurological disorder Parkinson's Disease in a disturbance of dreaming sleep.

Sleep and Lack of Sleep - Seen from the Cell Perspective

Neurobiology is a field from which, in future, a great deal of progress in understanding sleep can be expected. Professor Allan Pack from the University of Philadelphia does research in this field. He presented his newest results. His research group has studied sleeping worms (C. elegans) and insects (Drosophila), and, through molecular biological analysis of their cells, identified a signal line for sleeping - waking regulation. One may assume, Pack said, that this system has been retained through the course of evolution, in principle, in all living beings.

Professor Alan Pack in a discussion with a participant.

The consequences of a lack of sleep could be observed on the molecular level by his research group: studies on laboratory animals show that, by deprivation of sleep, a certain protein is increasingly released in the brain. If this protein, which plays an important role in the cells' repair mechanism, is released in large amounts, it prevents vital cell components from being formed. This has consequences for human beings: "We humans are programmed to stay awake for 16 hours; the longer we stay awake beyond that, the greater the limitations," said Pack.

Sleep Research and Traffic Safety

The physicist Wilhelm E. Kincses and the electromechanical technician, Siegfried Rothe, demonstrated on the example of applied research on sleep at the Daimler AG how findings of sleep research can contribute to traffic safety. The motivation for their research was the immense damage caused by fatigue at the steering wheel: "19% of all truck accidents on the highways with deaths or injury were caused by driver fatigue," Kincses said. If one adds the highway accidents with personal injury caused by overtired automobile drivers, the economic costs amount to more than 100 million Euros per year, according to the figures of the German Centre for Aerospace (DLR).

Siegfried Rothe and Dr. Wilhelm E. Kincses from the Daimler AG do research to improve the working conditions for truck drivers and for the prevention of sleep attacks.

His colleague Rothe said, "In my work, I try to contribute to preventing accidents completely". He tests which measures can improve truck drivers' deep sleep in order to restore sleep's refreshing effects. This is a matter of banning the noise in highway service areas out of the driver's cabin. Tests show that, besides insulating the cabin, even quite simple methods are effective - for instance, parking the truck in the service area with the loading space turned towards the highway, so that the driver's cabin is shielded from the traffic noise. Tests with truck drivers showed that measures for promoting deep sleep make sleep more relaxing and even vitalising.

In the audience: The foundation's CEO, Dr. Joerg Klein, and both of the members of the Executive Board, Professor Eckard Minx and Professor Rainer Dietrich.

Measures like, for example, the installation of a massaging seat, can stabilise the driver's condition while he is driving. Studies by a colleague showed that a reduced ability to concentrate and reduced reactivity caused by troubled sleep are accompanied by a complete misjudgement of one's own performance capacity. During experimental rounds of more than 430 kms, the drivers were interviewed at fixed intervals, an EEG taken, and their behaviour recorded on video. The results: The longer the drivers were on the road, the more their self-assessment and their actual reaction time diverged. According to Kincses, "The more fatigued one becomes, the more difficult it is to judge one's own condition."

Do We Need an Interdisciplinary Competence Centre on Sleep?

According to Thomas Penzel's data, there is a total of 280 accredited sleep laboratories and centres of sleep medicine in Germany. In the panel discussion in the afternoon, which was concerned with sleep research from the viewpoint of research policy, the psychiatrist and sleep researcher, Professor Thomas Pollmaecher (Clinic Ingolstadt), said that this clinical capacity would suffice to examine patients and to diagnose sleep disorders. But, in his view, it would be urgently necessary to establish independent, academically-based research, as well as training for physicians in the field of sleep medicine.

				Participants in the panel discussion (clockwise): Professor Rudolf Tauber, Dr. Christian Gravert, Dr. Reinhard Breuer (Moderator), Professor Thomas Penzel, and Professor Thomas Pollmaecher.

  

Particularly when drawing up working-shift plans, one is dependent on cooperation with research, as the occupational physiologist Christian Gravert (Deutsche Bahn AG) emphasized: "We used to think that, from the standpoint of industrial medicine, quickly rotating shifts would be the optimum. Now, we're thinking more about individually-tailored solutions." Thomas Pollmaecher indicated how research can contribute to answering this question: "We have to find out which shift models are best tolerated, and which individual differences there are, for example, genetically-, but also age-related ones."

The research dean at the Charité Berlin, Professor Rudolf Tauber, advised orienting oneself for organising a competence centre for sleep research, resp., sleep medicine on the existing centres for tumor medicine. There, all of the pertinent disciplines work together in networks, in a sort of virtual building, in the study of cancerous diseases. Of course, a start-up financing would be needed. First of all, however, it is a question of developing a specific concept and of constructing a stable network. "The Interdisciplinary Centre of Sleep Medicine at the Charité could be the nucleus for this type of network," as Tauber said.

Sleep - A Resource for Health and Efficiency

Sleep is not Death's Brother - as the great lyrical poet Franck greeted it -, is the résumé drawn by Professor Rainer Dietrich at the close of the lectures. "Sleep is much rather Life's Brother," said Dietrich - a Member of the Executive Board of the Gottlieb Daimler and Karl Benz Foundation. Dr. med. Ingo Fietze, Director of the Centre of Sleep Medicine at the Charité, took up the task of measuring another myth on the results of sleep research in his evening lecture. He answered the question, "Learning and Working Asleep - Myth or Reality?", by presenting studies on the relationship between sleep and best performance in sport and art. One of the most important results of a project for the study of sleep among members of the Ballett Ensemble of Berlin's State Opera was that a sound-protected retreat (a "quiet room") was furnished for the dancers. The "sleep doctor" advised not only the State Ballett, but, in general, to compensate disturbed sleep with a noonday nap: "A midday nap reduces mortality caused by cardiovascular diseases by 30%," Fietze said. In this manner, a greater effect could be attained than through exercise. Even a 10- to 30-minute nap is sufficient to restore wakefulness. It has, further, become known that, in high-performance sports, the 24 hours of the day are structured in sleeping- and waking "windows". Accordingly, there are certain times when we are in our best form.

They also came: Fellows of the foundation, here together with the Fellowship Programme's manager, Petra Jung (third from left).

This individually slightly varying rhythm can also be upset - for example, by jet lag. The US-American National Football League takes these problems into consideration in planning the seasons - if one of the teams has to fly through several time zones across the North American continent.

Productive sleep - in this statement, there is, according to the sleep researcher's opinion, in any case more reality than myth.

You can find further information and podcasts of the lectures including the English spoken lecture of Allan Pack in the German-language version.

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