Jet lag causes long term lag in cognitive performance

A group of Syrian hamster’s made the long haul flight from New York to Paris twice a week for four weeks.

Okay, they didn’t actually get on board the plane, but the lighting was changed to simulate the change in time zones, so the animals suffered from jet lag.

Why jet lag happens

Jet lag happens when several time zones are crossed in a short period of time. The reason for the problem is that the internal 24 hour clock, that drives much of our basic physiology, is no longer synchronized with the day/night cycle. This leaves problems such as feeling tired in the middle of the day and wide awake in the middle of the night. The trouble persists until the two clocks are once again aligned. This usually takes a few days.

Jet lag causes brain lag

The “jet lagged” hamsters found it more difficult to learn simple tasks which “normal” hamsters ace. No big surprise here – personally experienced some of these cognitive disturbances when traveling.

My taxi ride from the airport to the hotel in Hanoi nearly turned into an outlandishly expensive ride, when the taxi driver exploited the combination of jet lag and a currency with a zillion zeros. Fortunately, the scrooge in me managed to kick in and avoid the debarcle.

The big surprise in the study came when it was discovered that the hamsters were still a little intellectually wobbly, over a month after they returned to their regular day-night schedule.

Disturbingly, the intellectual deficit could be traced to structual changes inside the brains of the traveling hamsters. These hamsters had significantly fewer neurons in their hippocampus (part of the brain involved in memory processing). The researchers did quite a few tests and concluded that the jet lag, and not stress, decreased neurogenesis (neuron formation) in the hippocampus.

Flying is hazardous for your health

No need to cancel the plans for your next holiday – remember the hamsters made the trip twice a week for a month. But maybe time for a rethink of career options if you are a flight attendant serving this route. The job may be hazardous for your health long term.