Narrator: This is Science Today. For the first time, researchers have conducted a controlled trial of the effects of jet lag on the brain and memory function. Lance Kriegsfeld, an associate professor of psychology at the University of California, Berkeley, led the study.
Kriegsfeld: We jetlagged hamsters twice a week by shifting the light/dark cycle six hours, which was equivalent to a flight from New York to Paris. We did this eight times for a total of one month and found that, not surprisingly, the animals found it difficult to learn a very simple task.
Narrator: But what was surprising was the finding that these effects persisted a month later, after the jetlagged hamsters returned to a regular day-night schedule.
Kriegsfeld: They produced 50 percent less neurons in their brain than normal adult animals do when they're not jetlagged.
Narrator: Since millions of shift workers in this country may be affected by chronic jet lag symptoms, Kriegsfeld says the next step will be finding out the root cause of these changes in the brain. For Science Today, I'm Larissa Branin.