It is tempting to go to bed with your Ipad and read a book for an hour or so before sleep, or maybe just to reply to some emails or perhaps chat with your
friends on facebook, or similar.
This is not a good idea though, not unless you want to sleep well that night. Researchers are now saying that using gadgets with a backlit display, such
as Ipads, other tablets and most phones for more than one hour before bed can disrupt your sleep.
A study conducted by scientists from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute shows that a two-hour exposure to electronic
devices with self-luminous "backlit" displays causes melatonin suppression, which might lead to delayed bedtimes, especially in teens.
In order to simulate typical usage of these devices, 13 individuals used self-luminous tablets to read, play games, and watch movies.
The actual melatonin suppression values after 60 minutes were very similar to those estimated for spending an hour in sunlight and was not deemed significant.
However, after a two-hour exposure there was significant suppression.
"Our study shows that a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22 percent.
Stimulating the human circadian system to this level may affect sleep in those using the devices prior to bedtime," said Mariana Figueiro, associate
professor and team leader
Melatonin is a hormone produced by the pineal gland at night and under conditions of darkness in both diurnal and nocturnal species.
It is a "timing messenger," signaling nighttime information throughout the body. Exposure to light at night, especially short-wavelength light, can slow or even
cease nocturnal melatonin production.
Suppression of melatonin by light at night resulting in circadian disruption has been implicated in sleep disturbances, increased risk for diabetes and obesity,
as well as increased risk for more serious diseases, such as breast cancer, if circadian disruption occurs for many consecutive years, such as in nightshift workers.
Using your Ipad before going to bed can cause sleep problems.
Tablet display was found to suppress the body's sleep chemicals and researchers called for manufacturers of gadget to test how their products could
be affecting sleep patterns.
"In the future, manufacturers might be able to use data and predictive models to design tablets for tailored daytime light exposures that minimize s
ymptoms of seasonal affective disorder, and sleep disorders in seniors," the researchers wrote in their science paper.
"Technology developments have led to bigger and brighter televisions, computer screens, and cell phones," said Britanny Wood, who used the study
as the basis for her master's thesis.
"To produce white light, these electronic devices must emit light at short wavelengths, which makes them potential sources for suppressing or
delaying the onset of melatonin in the evening, reducing sleep duration and disrupting sleep.
This is particularly worrisome in populations such
as young adults and adolescents, who already tend to be night owls."
Tractor Beams Of Light -
No Longer Pure Science Fiction!
Science fiction meets real science! "Tractor beams" - fascinating invisible beams that can push and pull objects, leave science fiction domain.
The concept of "tractor beam" used in science fiction films and books to haul spaceships and capture floating capsules gains scientific attention.