Public Release:  Using math to take the lag out of jet lag

PLOS

Researchers at Brigham and Women's Hospital and the University of Michigan have developed a software program that prescribes a regimen for avoiding jet lag using timed light exposure. The method is described in an article published June 19 in the open-access journal PLoS Computational Biology.

Traveling across several times zones can cause an individual to experience jet lag, which includes trouble sleeping at night and difficulty remaining awake during the day. These effects largely reflect de-synchronization between the body's internal time clock and local environmental cues.

The program, which seeks to re-synchronize the body with its new environment, considers inputs like background light level and the number of time zones traveled. Then, based on a mathematical model, the program gives users exact times of the day when they should apply countermeasures such as bright light to intervene and reduce the effects of jet lag.

Timed light exposure is a well known synchronization method, and when used properly, this intervention can reset an individual's internal clock to align with local time. The result is more efficient sleep, a decrease in fatigue, and an increase in cognitive performance. Poorly timed light exposure can prolong the re-synchronization process.

Using their computational method, researchers simulated shifting sleep-wake schedules and the subsequent light interventions for realigning internal clocks with local time. They found that the mathematical computation resulted in quicker design of schedules and also predictions of substantial performance improvements. They were able to show that the computation provided the optimal result for timing light exposure to reduce jet lag symptoms.

"Using this computation in a prototyped software application allows a user to set a background light level and the number of time zones traveled to obtain a recommendation of when to expose a subject to bright light, such as the bright lights sometimes used to treat Seasonal Affective Disorder" said lead-author Dennis Dean. "Although this method is not yet available to the public, it has direct implications for designing schedules for jet lag, shift-work, and extreme environments, such as in space, undersea or in polar regions."

"This work shows how interventions can cut the number of days needed to adjust to a new time zone by half," said co-author Daniel Forger.

The next phase of this research includes the addition of interventions such as naps, caffeine and melatonin to help the process of realigning the internal body clock while reducing decreased performance experienced during travel across time zones.

###

To learn more about why sleep matters, the science behind it and how to improve your sleep, visit http://healthysleep.med.harvard.edu/.

FINANCIAL DISCLOSURE: The work described in this article was supported by US AFOSR F49620-95-1-0388 and F49620-95-1-0388, NASA Cooperative Agreement NCC 9󈞦 with NSBRI HPF-00405, NIH M01-RR02635 and NIH R01-NS36590. EBK is also supported by NIH K02-HD045459. DBF is an AFOSR Young investigator. DAD is also supported by T32 HL07901-10. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

COMPETING INTERESTS: The authors have declared that no competing interests exist.

PLEASE ADD THIS LINK TO THE PUBLISHED ARTICLE IN ONLINE VERSIONS OF YOUR REPORT: http://dx.plos.org/10.1371/journal.pcbi.1000418 (link will go live upon embargo lift)

PLEASE MENTION THE OPEN ACCESS JOURNAL PLoS COMPUTATIONAL BIOLOGY (www.ploscompbiol.org) AS THE SOURCE FOR THIS ARTICLE AND PROVIDE A LINK TO THE FREELY AVAILABLE TEXT. THANK YOU.

PLoS Computational Biology is an open-access, peer-reviewed journal published weekly by the Public Library of Science (PLoS) as the official journal of the International Society for Computational Biology (ISCB).

CITATION: Dean DA II, Forger DB, Klerman EB (2009) Taking the Lag out of Jet Lag through Model-Based Schedule Design. PLoS Comput Biol 5(6): e1000418. doi:10.1371/journal.pcbi.1000418

CONTACT:

Lori J. Shanks
ljshanks@partners.org
(617) 534-1604

Nicole Casal Moore
ncmoore@umich.edu
(734) 647-1838

Disclaimer

This press release refers to an upcoming article in PLoS Computational Biology. The release is provided by the article authors and their institutions. Any opinions expressed in this release or article are the personal views of the journal staff and/or article contributors, and do not necessarily represent the views or policies of PLoS. PLoS expressly disclaims any and all warranties and liability in connection with the information found in the releases and articles and your use of such information.

About PLoS Computational Biology

PLoS Computational Biology (www.ploscompbiol.org) features works of exceptional significance that further our understanding of living systems at all scales through the application of computational methods. All works published in PLoS Computational Biology are open access. Everything is immediately available subject only to the condition that the original authorship and source are properly attributed. Copyright is retained by the authors. The Public Library of Science uses the Creative Commons Attribution License.

About the Public Library of Science

The Public Library of Science (PLoS) is a non-profit organization of scientists and physicians committed to making the world's scientific and medical literature a freely available public resource. For more information, visit http://www.plos.org.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.