ARE YOU DEPRESSED? ASK YOUR COMPUTER THEN

Using your laptop or tablet in the evenings could put you at risk from depression, according to a new study.

Researchers have found exposure to bright light at night elevates levels of a stress hormone in the body which triggers the condition and reduces the ability to learn.

Study leader Samer Hattar, from Johns Hopkins University in the U.S, said: 'Basically, what we found is that chronic exposure to bright light - even the kind of light you experience in your own living room at home or in the workplace at night if you are a shift worker - elevates levels of a certain stress hormone in the body, which results in depression and lowers cognitive function

Up until the invention of electricity, humans rose with the sun and slept when it set. However, since then people can now work, play or party into the early hours.

The new study on mice found this typical 21st Century scenario may come at a serious cost.

It demonstrates how special cells in the eye - called intrinsically photosensitive retinal ganglion cells, or ipRGCs - are activated by bright light, affecting the brain’s centre for mood, memory and learning.

Prof Hattar added: 'Mice and humans are actually very much alike in many ways, and one is that they have these ipRGCs in their eyes, which affect them the same way.

'In addition, in this study, we make reference to previous studies on humans, which show that light does, indeed, impact the human brain’s limbic system. And the same pathways are in place in mice.'

The scientists knew that shorter days in the winter cause some people to develop a form of depression known as 'seasonal affective disorder' - or SAD - and that some patients with the mood disorder benefit from 'light therapy' which is simple, regular exposure to bright light.

-adapted from Daily Mail