Chronobiology (SLEE5007)


Aims: To understand the presence and physiological basis of biological rhythms and the ramifications for the sleep-wake cycle; to understand the normal modulation of circadian cycles and the effects when these are disrupted. Content: Chronobiology: The circadian rhythm and its relationship to the sleep cycle is examined along with the concepts of photic and nonphotic zeitgebers. Neural basis of Circadian Rhythm. The neurophysiology of the pacemaker in the suprachiasmatic nucleus and the neural circuits modulating its function. The genetic basis of circadian rhythm generation will also be discussed. Effects of Circadian Rhythms on Physiology I: The internal sleep structure is governed by circadian rhythms and these rhythms also impact upon levels of alertness and cognitive performance. This module deals with this topic and the ramifications for general day-time performance and quality of life if these rhythms are disrupted such as with sleep fragmentation or jet lag. Effects of Circadian Rhythms on Physiology II: This module continues the themes of 2.1.3 and considers the effects of such things as sleep deprivation and shift work on homeostasis and sleep regulation. In addition, the physiological effects and role of chronobiotic agent such as melatonin will be introduced. Circadian Rhythms and Ageing: The timing of sleep wake cycles is controlled by at least two neural clocks in the brain. Throughout the animal world there are numerous examples of cellular clocks, with the sleep wake cycle being the most visible example. Sleep wake patterns and rhythms change with age with alterations in both timing and content of sleep. This module introduces the area of chronobiology and the changes in sleep wake patterns with ageing. Importance of Sleep: Sleep occupies about one third of life and there is clear evidence of its importance for the wellbeing and proper function of many animals. This module provides an introduction to the evidence for the key role of sleep in growth, development and brain function.

Further unit of study information


~3 hours online lectures over 1 semester plus directed reading and independent study


1xonline quiz (40%), 1xexam (60%)

Faculty/department permission required?


Study this unit outside a degree

Non-award/non-degree study

If you wish to undertake one or more units of study (subjects) for your own interest but not towards a degree, you may enrol in single units as a non-award student.

Cross-institutional study

If you are from another Australian tertiary institution you may be permitted to underake cross-institutional study in one or more units of study at the University of Sydney.