To anyone who’s flown before, the answer to this question is something of a no-brainer. Under the influence of jet lag, your mind and body drift in and out of a haze – a haze sometimes held at bay with stimulants like caffeine – and when it finally comes time to sleep, you crash hard. This fuzzy-headed, fatiguing cycle repeats for a few days until you get “back on track” a few days later.
No quick rebound
Yet scientific research suggests that “getting back on track” may take longer than we think. A lot longer, sometimes more than 28 days to bring our brains back up to speed after disrupting our circadian rhythms with a time change. That’s almost the same amount of time it takes to work off a sleep debt.
Jet lag slows the brain
Scientists set out to see if jet lag had any effects on the brain’s ability to learn. In order to exercise more control in their experiment, they used hamsters instead of your typical frequent flyer. Researchers pushed the hamsters’ sleep schedule ahead to simulate jet lag, but they did not restrict sleep. The hamsters got their normal hamster amount of shut eye every day.
What did scientists discover? Under the simulation of jet lag, hamsters performed poorly on tasks that involved memory and learning throughout the experiment, even long after they had been returned to their “normal” time.
Memory, sleep and learning
We know that a lack of sleep can affect memory and impair learning. We also know that certain types of sleep are responsible for certain types of memory processing and learning.
However, was once assumed that as long as you got enough uninterrupted sleep, your body and brain would continue to function as normal. The poor learning abilities that showed up in the jet-lagged hamsters led researchers to ask:
“Does our internal biological clock influence certain brain functions associated with our intellect?”
Put another way:
“Is there a link between circadian rhythm and learning?”
In the case of the hamster study, the answer is maybe. There’s much more to investigate in order to link learning to circadian rhythms, including using humans to try and duplicate this particular study. But the study of the effects of circadian rhythms on memory, learning, and cognition are a fascinating and growing area of research.
Circadian influences are everywhere
We have a lot to learn about the full implications of circadian function in humans, but there’s already solid research about the effect circadian rhythms have on behavior, regardless of surroundings. Here are a couple intriguing examples:
- Botanists have observed that plants that appear to respond to light, like morning glories, are actually working off of an internal clock that tells their blossoms to open or close.
- Likewise, biologists have noted that marine animals continue to respond to daily tidal changes, even when removed from their normal environment.
While science continues to de-code the mysteries of circadian rhythm, we all can do our sleep and our health a favour by maintaining a consistent sleep schedule, to help keep those rhythms working as they should.