James Lyall MD FRCP Consultant Physician, Battle Hospital, Reading. In this article we will consider normal sleep patterns together with snoring, sleep related breathing disorders and the condition called obstructive sleep apnoea. We shall see how our normal sleep patterns may be disturbed by jet lag and shift work. Finally, advice will be given about how best to obtain help. The natural rhythm of sleep.
Nature tends to follow certain rhythms.
The spinning of the earth around its own axis dictates a daily rhythm, the moon has a monthly influence and the rotation of the earth around the sun determines the seasons. In common with all other animals we have our own in-built natural rhythms. For example, we have a spontaneous circadian daily rhythm and the reproductive cycle has a monthly rhythm. Curiously, our daily rhythm is approximately 25 hours and is reset to 24 hours by the time clues given by our environment. During this 24 hour cycle there are two periods when the ability to fall asleep is greatly enhanced.