A switched on laptop with a closed lid next to the bed is unlikely to negatively affect health and quality of sleep. There are many electrical appliances around us, the work of which we simply do not notice, a laptop is the same source of electromagnetic radiation as a refrigerator, a home router with wi-fi, radio waves and many other achievements of human civilization.
Only a switched on laptop with an open lid can harm your health. The bright light from the display suppresses the production of melatonin, also called the "sleep hormone". This will make it much more difficult to fall asleep, and the quality of sleep and life will decrease. But even in this case, the device will sooner or later go to standby mode with reduced power consumption - the display will turn off, coolers will stop working and make noise.
But if you don't have any urgent need to hold a laptop next to the bed, it's better to move it away. It can become a distraction . Everyone loves to scroll through the social media feed before bed, and a laptop lying next to you is a great temptation to indulge yourself with memes and interesting videos, instead of a good rest. Not only will you reduce the duration of sleep, but it will also make it more difficult for you to fall asleep due to the negative effects of light on the production of melatonin.
Somnologists generally do not recommend using gadgets before bed. Instead, they recommend walking, reading and meditation.
What if the laptop is in the room, but out of sight?
Also, is there any research on the impact of wifi on sleep quality?
(In the comments, why 140 characters ???? Why provoke the writing of watery posts?)
Yes, of course. First of all, it affects the quality of sleep. During sleep, the important hormone melatonin is produced. The better you sleep, the better it is produced, the higher your quality of life, at least for a day. For better melatonin production, it is important to fall asleep in the dark. That is, any source of light, be it a TV, laptop, bedside lamp or light from the street, not only prevents you from falling asleep, but also interferes with important processes in the body. We advise generally sleeping with a special sleep bandage. Well, put the laptop away. :)
We also remind you that for a good sleep it is better to remove the sources of "blue light", and this is just your smartphone or laptop - two hours before going to bed.