Frequent flyers who repeatedly endure jet lag may be permanently damaging their brain.
Jet lag occurs when a person travels over a number of time zones and disrupts the standard circadian rhythms which regulates the times at which a human will wake up and go to sleep. The usual symptoms of jet lag include exhaustion, disorientation and difficulty sleeping. The condition may last several days before the traveller is fully adjusted to the new time zone; a recovery period of one day per time zone crossed is a suggested guideline.
A University of Bristol study, published in the journal “Nature Neuroscience”, studied the brains of 20 female aircrew who regularly flew between 7 different time zones. The study found that, for the aircrew who suffered the most jet lag there was no deficit of language. However, results found that certain short-term objective memory and very simple abstract cognition was affected. The paper pointed out that it may not be possible to “recover” from such brain damage if suffered repeatedly over the long-term.
A separate study by the University of California, looked at the link between jet lag and Alzheimer’s memory loss. The study, conducted on mice, found that disturbances in the body’s day-night cycle, cause chemical changes in the brain and may cause both learning and memory loss associated with Alzheimer’s disease. People who suffer from Alzheimer’s usually have problems sleeping, and scientists do not completely understand why.
Dr Brewer, who lead the study at the University of California, asserted that: “the issue is whether poor sleep accelerates the development of Alzheimer’s disease or vice versa … It’s a chicken-or-egg dilemma, but our research points to disruption of sleep as the accelerator of memory loss.”
Dr Robert Sack, of the Sleep Disorders Medicine Clinic at the Oregan Health Sciences University in Portland, added: “It’s interesting because we think of jet lag as a kind of nuisance, but this study would suggest that it may have more serious consequences.”