Michael A. Nitsche

Director of the Dept. Psychology and Neurosciences at the Leibniz Research Centre for Working Environment and Human Factors in Dortmun

Presentation title: Circadian impact on brain physiology, and cognitive performance

Abstract：

Circadian rhythms are controlled by internal, genetically driven Zeitgebers, and determine daytime-dependent physiology. Moreover, it has been shown that time of day also affects cognitive functions in humans, and that genetically driven interindividual differences of circadian rhythms, as in late and early chronotypes, have a relevant impact. How exactly the effect of circadian rhythm-dependent brain physiology affects cognitive performance in humans is however largely unexplored. We explored the impact of sleep deprivation, and chronotype on learning and memory formation, and executive functions in healthy humans, and identified accompanying cortical excitability, and plasticity, which are important physiological derivates of cognitive performance. Cognitive performance was reduced in both, humans under sleep deprivation, and chronotypes at the non-preferred time of the day. The underlying physiology however differed in these conditions. Whereas plasticity, and cortical excitability were reduced in chronotypes during the non-preferred daytime, sleep deprivation resulted in enhanced cortical excitability, and conversion of plasticity. These results show that optimal performance depend on time of day in relation to chronotype, and sufficient sleep, and delivers relevant information about organization of work, but also therapy, including rehabilitation, to achieve optimal effects. 

Biography:

Michael A. Nitscheis Director of the Dept. Psychology and Neurosciences at the Leibniz Research Centre for Working Environment and Human Factors in Dortmund. He studied Psychology and Medicine at the Georg-August-University in Goettingen, and performed his Dissertation in Medicine at the Max-Planck-Institute for Biophysical Chemistry in Goettingen. From 1999-2015, he was resident and consultant at the Dept. Clinical Neurophysiology of the University Medical Center in Goettingen. He is a leading expert in plasticity research in humans, including non-invasive brain stimulation, neuropsychopharmacology, and cognition, and together with Walter Paulus developed tDCS. He received grants from various funding organizations, including the German Research Foundation, and the European Union, and published more than 300 papers in international peer-reviewed journals. He received the Alois Kornmüller, and Richard Jung Awards by the German Society of Clinical Neurophysiology, and the GESET Award by the German Society of Electrostimulation and Electrotherapy for his work on non-invasive brain stimulation in humans, and is member of the Leopoldina.