Living, eating, sleeping and stumbling around in complete darkness for a week sounds terrifying to most.
But that’s the premise of a new bizarre reality TV show Scared of The Dark.
The show will see eight celebrities live for eight days and compete in challenges in the dark while being tracked by 50 infrared cameras.
But how well can you actually function in complete darkness and what are the health risks of being so deprived of light?
Here MailOnline reveals how plunging yourself into darkness can cause exaggerated emotions, hallucinations and extreme fatigue.
Channel 4’s latest series Scared Of The Dark, hosted by Danny Dyer, features retired pro boxer Nicola Adams, reality star Chloe Burrows, Eubank, Gazza, singer Max George, comedian Chris McCausland, TV personality Scarlett Moffatt and actress Donna Preston all live, sleeping and eating in the dark
In the TV show, hosted by Danny Dyer, eight celebrities will battle with the psychological pressure of mild deprivation as they face challenges.
Retired pro boxer Nicola Adams, reality star Chloe Burrows, Eubank, Gazza, singer Max George, comedian Chris McCausland, TV personality Scarlett Moffatt and actress Donna Preston are all participating.
Every movement during the tasks is observed by clinical psychologist Dr. T.
He is on hand to explain the emerging relationships between the celebrities and what is happening to them emotionally and physiologically; both individually and collectively as a group.
But spending an entire week in the dark can take a toll on both your physical and mental health, according to Professor Russell Foster, a circadian neuroscientist at the University of Oxford and director of the Nuffield Laboratory of Ophthalmology.
It can cause sleep deprivation, a rise in blood pressure and psychological problems.
Feeling of jet lag
Living in the dark can throw your internal body clock out of sync.
The sleep-wake cycle, known as your circadian rhythm, is set on a natural clock that regulates your sleep, digestion, body temperature, and hormones. We need sunlight for it to function.
When you change time zones or when the clock moves forward or back an hour, your sleep cycle becomes misaligned. Living in darkness can have the same effect.
Professor Foster said: ‘Why we need light is that the internal body clock has to be set to the outside world. If you don’t get that daily exposure to light, the human body clock, which is a little longer than 24 hours, will go through time.
‘On average you get up 10 or 15 minutes later every day and go to bed. So the clock will be skewed in relation to the outside world.’
This can lead to sleep deprivation, but it can also put stress on your internal organs.
However, he noted that life under these conditions for a week – the duration of the Channel 4 show – won’t change much.
He added, “If [they live in darkness] over long periods of time, we know this can cause problems. For example, changes in metabolism, changes in mood, changes in everything.
“But only for a week, I suspect they won’t see much.”
This moment from the trailer appears to show the contestants trapped in a number of cages in the dark
Low mood
Even long winter days are enough to make people’s moods drop.
Although seasonal affective disorder (SAD) is not fully understood, the shorter autumn and winter days with less sunlight are believed to trigger depression in some people, the NHS says.
The main theory is that a lack of sunlight can cause a part of the brain called the hypothalamus to malfunction.
This can affect the production of melatonin, the hormone that makes you feel sleepy, and cause your body to produce too much of it.
It can also lead to a lower production of serotonin, a natural chemical that affects your mood, appetite and sleep, which can make you feel depressed.
But it’s not just a lack of melatonin and serotonin that can cause your mood to plummet.
Professor Foster says the circadian rhythm disruption is enough to make you feel down, especially if you’re predisposed to depression in the first place.
He said: “They can have some mood swings at the end of it because even relatively short periods of sleep disruption and internal desynchronization can affect mood quite quickly.
“If you were vulnerable to mental health or depression, things like this could have a negative impact on you.”
Increases risk of stroke
Spending days in the dark is probably not much of a problem if you’re healthy.
But experts warn that it could have serious consequences for people with health conditions, including stroke.
“I wouldn’t let anyone in [to the Channel 4 reality show] if they had a pre-existing health condition, such as high blood pressure,” says Professor Foster.
He added, “It could be a bit like shift work, where you’re essentially forcing your body to work against its internal clock.”
Research shows that the combination of sleep deprivation and circadian rhythm disruption can potentially trigger a stroke.
Professor Foster, who has written a bestseller on circadian rhythms, said the increased risk is theoretically all due to the side effect of high blood pressure.
High blood pressure can cause blood clots to form and block blood flow in the arteries leading to the brain.
This causes brain cells to begin to die, which causes the telltale signs of a stroke, such as slurred speech and weakness on one side of the body.
In 2016, researchers investigating the link found an eight percent increase in stroke hospitalizations in the two-day period after the clock moved forward or backward.
Results of the studylooking at more than 15,000 people also showed that the risk was higher for those over 65.
But Professor Foster believes the same disruption and stress can be caused by not seeing sunlight.
He said, “If you’re healthy, it won’t have much of an impact, but if you have a pre-existing health condition, you’re challenging the body in a way that could actually push you into a health problem, whether that’s mental health, cardiovascular problems, intestinal problems.’
Eye damage
While no one can see in total darkness, your eyes do their best to adapt.
Usually there is always some light available, even if it’s just starlight, which is enough to get your eyes used to it.
But in the reality show Scared of The Dark, the celebrities will have no light at all.
When you’re in the dark, the pupils dilate as much as possible so they can absorb more of what little light there is, wrote Professor Mark Fairchild, a color science expert at the Rochester Institute of Technology in The conversation.
After about 10 minutes in a dark room, your pupils open more in an attempt to let in light, and after 20 minutes they’ll be doing their best to see as well as possible in the dark, says Professor Fairchild.
So after a week of trying to adjust to the darkness, your eyes may struggle to cope with bright light.
Professor Foster said: ‘For vision a short period of time won’t be a problem, but when they appear in the light that needs to be stepped up.
‘The eye tries to maximize its ability to detect light because it is in the dark.
‘So when [the reality TV stars] transition from dark to light, I hope that’s not an abrupt change, because the eyes can be sensitive.’
The brain exaggerates everything
If you rely only on touch and hearing, your brain can play tricks on you.
It can range from hallucinations to feeling exaggerated emotions.
Professor Foster said: ‘If we don’t have eyesight, we can exaggerate experiences because the mind is looking for information.
“What you could do is exaggerate some of the emotions that would occur if you can’t feel what’s going on, it’s a deep and deep insecurity.
“You’re expected to do things that can be real challenges because you’re very suddenly isolated from the world we know and navigate.”
So the celebrities may find that they find the challenges more difficult to complete.
If you experience vision loss over a long period of time, your other senses begin to compensate.
Professor Foster said, “If you’ve lost your eyes, your brain will rewire them, but there probably won’t be much in this short time.”
This feeling of exaggeration is even worse when you are also in isolation.
People who are in isolation and darkness experience hallucinations.
The lack of stimuli causes people to misattribute their thoughts and feelings to the outside world, according to one article in The Conversation by Sarita Robinson, a physiologist at the University of Central Lancashire.