Jet Lag lingers
Jet lag is a relatively minor annoyance for people who cross time zones by air. Most of us however, will return to normal within a few days. For those, like flight attendants and politicians, who cross back and forth across time zones the effects are much more serious and long term.
Jet lag results when you cross several time zones in a short period of time. For most of us this means travelling in a plane. We donâ€™t whether â€œdimension lagâ€ will occur once time travel mechanisms are perfected but the signs are encouraging that Captain Kirk, Mr Spock and company could dissolve and reform without any apparent side-effects. For us though, when we enter a time zone that is not in synch with our internal clock then we experience jet-lag until the internal clock is re-synched by sufficient exposure to light in the new zone.
The short-term effects can be anything from general malaise to digestive upsets. In the long term though, regular travellers may experience problems with memory and learning and even worse.
To examine this researchers studied hamsters. They chose hamsters because these earnest and yet oddly whimsical rodents are classical biological models of the circadian rhythm. So tightly controlled are the rhythms of a hamster that females will ovulate every 96 hours to within a window of a few minutes. Hence the expression, â€œpunctual as a hamsterâ€.
For the study twice a week for four weeks hamsters were subjected to six-hour time shifts that are the equivalent for a New York to Paris air flight for humans. During the last two weeks of the study and for a month after it the hamsterâ€™s performance on memory and learning tests was measured.
As was to be expected, during the jet lag phase of the experiment the jet-setting hamsters did worse on the tests than a control hamster group. The surprising result was that these deficits continued for a month after the hamsters had returned to their normal day-night patterns. Additionally, the researchers found changes in the brain that continued after the study had finished.
The jet-lagged hamsters had 50 per cent less new neurons in the hippocampus, a part of the brain involved in memory, compared to other hamsters. New neurons are constantly being added to the adult hippocampus and are thought to be involved in learning. Memory problems are known to be associated with a drop in cell development in the hippocampus.
The implications of this study are disturbing enough for individuals, especially those whose work involves crossing time zones, but what about the politicians that fly the globe on tight itineraries where one high level meeting after another is planned for weeks on end? What sort of decisions are they making based on their jaded, jet-lagged faculties?
Perhaps all political meetings should be conducted online to avoid the physical and mental demands on our venerated leaders. Either that or each politician should be assigned a hamster with the hamster becoming a kind of jet lag barometer: if the hamster shows signs of wear and tear then all meetings are off. Alternately, if the politician shows signs of faltering then the hamster could be called in to conduct negotiations. We would probably all be better off if that happened: thereâ€™d be a lot less war and a lot more cheese.