We are what we repeatedly do. Excellence, then, is not an act, but a habit. Aristotle
Entrainment in humans
Normally all humans are entrained (synchronised) to environmental time, that is, they are awake in one interval of the 24 h-day and sleep in another. There are only few exceptions, the great majority of whom are totally blind subjects. The evolutionary value of entrainment is clear. It allows for optimal performance at the right time of day, because being able to anticipate future tasks engenders the appropriate physiological and psychological preparation. However, the state of entrainment varies dramatically between individuals, the so-called “chronotypes”. Early chronotypes or "larks", those who rise early and go to bed early, fit better into society’s norms than late chronotypes or "owls". Entrainment can also have its disadvantages, since our modern society often imposes deviations from the regular work-rest scheme, as in shift work. Failure to adapt to environmental and sociological-societal pressures leads to misalignment of the internal biological clock. This ‘dys-entrainment’ comes with enhanced risk of errors and accidents, loss of productivity, and health risks (increased propensity for cancer, depression, sleep disturbances, gastrointestinal and cardiovascular disorders, decreased immune responses and life span). In addition, a certain shift schedule may be easy for one chronotype but almost impossible for another. Until now, little attention has been paid to these individual predispositions in the organisation of shift schedules. Study of extreme chronotypes in simulated phase shift conditions and optimisation of the effects of light on human circadian timing may provide the data required.
Sub-Project Leader: Prof. Dr. Anna Wirz-Justice, University of Basel, Centre for Chronobiology
- Prof. Dr. Till Roenneberg, Thomas Kantermann, LMU Munich, Institute for Medical Psychology
- Prof. Dr. Urs Albrecht, Corinne Jud, University of Fribourg, Division of Biochemistry
- Dr. Howard M. Cooper, Dr. Claude Gronfier, Department of Chronobiology, Stem Cell and Brain Research Institute, INSERM Lyon
- Prof. Dr. Domien Beersma, Dr. Marijke Gordijn, University of Groningen, Chronobiology
- Prof. Dr. Debra J. Skene (deputy leader), University of Surrey, Centre for Chronobiology
- Prof. Dr. Frank Wilhelm, Dr. Vitaliy Kolodyazhniy, University of Basel, Institute for Psychology
- Prof. Dr. Christian Cajochen, Kurt Kräuchi, University of Basel, Centre for Chronobiology
- PD Dr. Anne Eckert, University of Basel, Neurobiology Laboratory
- Dr. Konstantin Danilenko, Oksana Sergejeva, Russian Academy of Medical Science, Institute of Internal Medicine
- Anand Kumar, Dr. Winni Hofman, Dr. Cees Lijzenga, Wendy van Ecke, Personal Health Institute International (PHIi)
- uha Hintsa, Luzian Wolf Sowoon Technologies
- Dr. Jakob M. Weber, Bühlmann Laboratories
Meeting of the human group at the EBRS 2009 in Strasbourg (August 2009)
Meeting of the human group at the SRBR 2008 in Sandestin (May 2008)
First "Human" EUCLOCK meeting in Eindhoven (July 2005)
from left to right: Jakob Weber (Bühlmann), Anand Kumar (PHI), Konstantin Danilenko (Russ. Acad. o. Med. Sc.), Dominicus Beersma (Groningen), Debra Skene (Surrey), Ninoslav Marina, Markku Ruokanen, Luzian Wolf (all Sowoon); Anna Wirz-Justice (taking photo)
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Wilhelm, F.H., Pfaltz, M.C., Michael, T., Blechert, J., Kolodyazhniy, V., Margraf, J., & Grossman, P. (2007). Attenuated metabolic-cardiorespiratory coupling during daily life in patients with anxiety disorders: exploration of a new phenomenon. Psychophysiology, 44, S12.
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