Most of us sleep 7-9 hours a day. But what is the role and function of sleep? What regulates it and how much do we really need? Is it true that our brain is either "on" (awake) or "off" (asleep)? If so, what triggers that switch?
These are just some of the questions answered by Dr Lederle in this fascinating insight into one of the most intriguing subjects of modern science: How we sleep, how we improve sleep and - most importantly - how we sleep well again.
Dr Katharina Lederle is the daughter of a German farmer. She studied Biosciences at Ruprecht-Karls University, Germany. She then completed a PhD on the Human Body Clock at the University of Surrey, U.K.

Source: Supplied
Dr Lederle lives in London and works as a human sleep and fatigue specialist.
Her book "Sleep Sense" was published at Exisle Publishing.
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