Sleep is a state of altered consciousness in which we become less aware of what’s going on around us. Sleep can take different forms in different animals. Dolphins, for example, sleep just half a brain at a time, and can even continue to swim while asleep.
For humans, sleep involves four stages, called N1, N2, N3 and rapid eye movement (REM). N1 is the lightest stage of sleep. It usually occurs right after you fall asleep, and typically lasts less than 10 minutes. During N2, you sink deeper into sleep. This stage is characterised by brief, high-amplitude brainwaves called ‘K-complexes’ and bursts of lower amplitude waves called ‘sleep spindles’. The N3 stage is the deepest stage of sleep, and is characterised by slow brain waves called delta waves. Finally, during REM sleep your brain activity and breathing rate speed up, and your eyes move quickly in lots of directions. Our most vivid dreams tend to occur in REM sleep, and our brain paralyses our muscles so that we’re unable to act them out. During the night, we continually cycle through these four sleep stages, with a full cycle taking around 90 minutes in adults.
HOW MUCH SLEEP DO WE ACTUALLY NEED?
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Could you be cryogenically frozen?
It’s a task harder than doing the Kessel Run in less than 12 parsecs
GATEWAY TO THE FUTURE
2022 will see NASA, with help from its international partners, take the first major step on humanity’s journey back to the Moon, and the start of a mission to establish an outpost alongside Earth’s natural satellite
A WHOLE NEW WORLD?
Technology has transformed our lives in the last couple of years. Will it continue to do so as we ring in 2022?
A VACCINE FOR CANCER
The pandemic derailed a lot of medical research. But the effort that was suddenly redirected towards developing a vaccine for COVID-19 may have helped us make important progress on at least one breakthrough: preventing cancer
PUTTING NATURE TO RIGHTS
More countries are enshrining the right to a clean environment into law. So if a company or government is impinging upon that right, you could take them to court
AUGMENTED INTELLIGENCE: A BETTER TYPE OF AI?
Why are we working so hard to make computers that compute better, when we could be using computers to help us think and act better?
IT'S TIME TO GET EXCITED ABOUT THE JAMES WEBB SPACE TELESCOPE
NASA’s most ambitious project yet will peer deep into space looking for clues about the birth of planets, stars and the evolution of the Universe itself
RUNNING CIRCLES AROUND DEPRESSION
Lacing up your trainers can help reduce your chances of developing depression
THE BIG BURNOUT
Long hours, low pay and a lack of appreciation — among other things — can make for a stressful workplace and lead to burnout. It’s something we should all be concerned about, because over half of the workforce reports feeling it
WHAT LIES BENEATH
The European Space Agency’s JUICE mission aims to peer beneath the icy surfaces of Jupiter’s moons to determine whether something could be living in the waters below
To do list
You're in Safe Hands with the Dolphins Safeties
After an off-season where the Miami Dolphins had daily drama surrounding who would be the quarterback, which coordinator was really calling the plays, and does their number one pick have a limp, went into Foxborough and did something they’ve only done once since 2008.
Offensive line an early season concern
Solid preseason offers hope for running game
How unlikely would it be if the answer to the Dolphins running game concerns is a former seventh-round pick in his third season out of Washington who was the last of 25 running backs taken in the 2019 draft?
Dolphins 101 with Professor Klump
Miami finally has their guy at quarterback
AROUND THE AFC EAST
Buffalo has their future QB...do the other teams?
It’s time for Baker to become elite
Time to take stock of Tua
The Dolphins quarterback showed improvement in his second camp, but the question remains as to how big a jump he can make in 2021
Biegel back with a new perspective
Instead of playing linebacker for the Miami Dolphins last season, Vince Biegel spent Sundays with his leg propped up and daughter on his knee.
Dolphins defense could use another playmaking linebacker
We understand that the offseason talk has centered on offense, and justifiably so. There are serious voids that must be filled both at running back and receiver. Just put in the tape from last season you’ll see that just about every Sunday.