If they have a running wheel in their cage, they love to run in it for hours, starting at about the same time every night. In fact, hamsters have a unique talent for telling time precisely, even when there are no external clues such as sunshine, room lights, or movement of other creatures. Some scientists study the time sense of hamsters to understand how the brain works, and to seek better treatments for sleep disorders, jet lag, and mental illnesses that may be caused by a faulty body clock. In this ongoing experiment, we are studying how medicines used to treat people with depression and other affective disorders may act on the body clock. A computer records every movement of the running wheel, and this data is analyzed to find out when he starts to run, how hard he runs, and when he stops.
Some hamsters drink regular water, and some drink water to which a medicine has been added.
The medicine is the same kind, and the same dosage range, that patients with mood disorders will take. The purpose of the experiment is to find out whether the medicine affects the timing of the biological rhythms of wheelrunning. Here is a live web cam of a German hamster . For more information about sleep and biological rhythm research in San Diego and elsewhere, see the San Diego Sleep and Rhythms site. The sleeping hamster picture, and the dancing hamster animation, came from p4room in Japan .