Desynchronosis, commonly known as Jet Lag, is a physiological condition, which is believed to be the result of interruption of the "light/dark" cycle that entrains the body's circadian rhythms. Circadian rhythms are approximate daily periodicity, a roughly-24-hour cycle in the biochemical, and physiological processes of living beings. These disturbances results from shift work, daylight saving time and change of time zone when traveling. For instance, when a person from Indian arrives in USA at midnight USA time, his or her body continues to operate on Indian time. As the body struggles to cope with the new schedule, temporary insomnia, fatigue, irritability, and an impaired ability to concentrate may set in. This happens because the brain becomes confused and disoriented as it attempts to organize to change of time zone.
The change in time zone causes our internal clock to be out of sync with the external environment. The cells in circadian clock react to differences in light between night and day, which allow us to anticipate changes in the environment by pacing the metabolism to daily cycle. According to Cornell University research, the circadian rhythms sense light through a process that transfers energy from light to chemical reactions in cells. This chemical reaction is caused by a protein called vivid, which contains chromophore – a light absorbing molecules. As stated in the research, the chromophore captures a photon or particle of light, and the captured energy from the light triggers a series of interactions that ultimately lead to conformational changes on the surface of the vivid protein. These structural changes on the proteins surface kick off a cascade of events that affect the expression of genes. Therefore, when the eye of an air traveler perceives dawn or dusk many hours earlier or later than usual, the hypothalamus may trigger activities that the rest of the body is not ready for, and jet lag occurs.