It’s one of life’s greatest mysteries – what happens when we die?

“During this time, people tend to become less well. They typically struggle to walk and become sleepier – managing to stay awake for shorter and shorter periods.

“Towards the last days of life, the ability to swallow tablets or consume food and drinks eludes them.

“It is around this time that we say people are ‘actively dying’, and we usually think this means they have two to three days to live.”

That being said, some people go through this process in just a day, while others continue on for nearly a week, which Coyle said is often distressing for the families.

He explained the actual moment of death is trickier to decipher, adding: “But a yet unpublished study suggests that, as people get closer to death, there is an increase in the body’s stress chemicals.

“For people with cancer, and maybe others, too, inflammatory markers go up. These are the chemicals that increase when the body is fighting an infection.”

One detail he was asked about is whether the last moments of life could be euphoric, perhaps triggered by a flood of endorphins.

Although Coyle couldn’t give a definitive answer as it hasn’t yet been explored, he did point to a 2011 study that showed the levels of the happy hormone serotonin tripled in the brains of six rats as they passed away.

“We can’t rule out the possibility that something similar could happen in humans,” he said.

As for the bit we’re all concerned about – pain – the doctor explained: “In general, it seems like people’s pain declines during the dying process.

“We don’t know why that is – it could be related to endorphins. Again, no research has yet been done on this.”

During his time in palliative care, Coyle has witnessed the full spectrum of deaths, from people who are anxious right up to the end to those who accept their fate early on.

“Ultimately, every death is different – and you can’t predict who is going to have a peaceful death,” he said.

“I think some of those I have seen die didn’t benefit from a rush of feel-good chemicals.

“I can think of a number of younger people in my care, for example, who found it difficult to accept that they were dying. They had young families and never settled during the dying process.

“Those I have seen who may have had an ecstatic experience towards the end of their lives were generally those who somehow embraced death and were at peace with the inevitability of it.”

Raychul, who goes by the handle @rayraydemp, posted a series of videos in which she described what she experienced when she was clinically dead for seven minutes.

Rather unsettlingly, she recalls voices relaying ‘what it means to be a good person’, and how time appeared to go on forever.

The TikToker opened up about overdosing while in college, saying: “I basically died for about seven minutes total but it felt like forever.”

When she first died, Raychul said she was ‘in an open field that had a giant tree in the middle with water in the front’.

She added: “There was no sense of space or relative to your size to your environment. It was gargantuan is an understatement.

“It was also endless, there was no horizon that you could really see to give you a space of how big this place was.

“All at once you heard a million voices all talking at the same time relaying information to you on what it means to be a good person, your interaction with other people and how it affects a multitude of individuals.”

In part two of her story, Raychul said that as soon as she was in this beautiful space she was then taken to what she could only describe as a ‘black pit’.

“The black pit was so scary and I still have nightmares about it if I can be honest,” she said.

“There’s hundreds of thousands of millions of people all in this space. We can see each other but we can’t talk to each other, you can’t really understand what anyone is saying.

“You just hear people screaming out like names and asking for their mum or for help and you can’t really see them, you can’t feel them, they’re just there.”

At this point, she came to in a rehab facility, which brings her to the third and final part of the story.

While undergoing extensive therapy for two months, Raychul said her therapist helped her work through a lot of trauma that led her to that point in her life.

When she started to explain her NDE, the therapist asked for permission to record and document the conversation.

Raychul explained: “I went through my entire experience with her from start to finish leading to that point.

“She took vigorous notes and asked me to describe where I had been. When I explained to her what was happening, when we were all done she looked at me and said, ‘This binder is full of near-death experiences and they’re all almost exactly like what you just described.’

“One folder contained 3,000 near-death experiences.”

Gulp. Unfortunately there’s not a lot we can do with this information, although the TikToker did go into a bit more detail about the voices saying what it means to be a good person: “When you go out to purposely hurt people. We’re all connected & you can change so many lives on one interaction.”

She also offered her view on the commenters who suggested she may have been in limbo, writing: “I don’t think it’s a waiting room. I honestly believe it’s a way to gather knowledge & change your soul.”

A man who came back from the dead after dying for 90 minutes has revealed what the afterlife is like – and his experience was so frightening that his brain has ‘blocked it out’.

She then tried to revive him for 20 minutes until an ambulance arrived.

However, when they got there, they only found his lifeless body.

Melinda had desperately tried to perform CPR until paramedics arrived, and it’s reported that he was clinically dead for an hour and a half.

Medics continued to work on Alistair for over an hour, giving him CPR and using a defibrillator to shock him eight times.

And, after a desperate 90 minutes, his pulse was found after his heart had finally restarted.

When describing the afterlife, Alistair says there was ‘nothing’, no sounds, voices or lights. He said that the experience was so traumatic that his brain had shut everything out.

“Technically, I was dead for 90 minutes,” he said.

“I remember going to bed on the Saturday night – and the next thing I remember was waking up on Thursday morning on a trolley going from ICU to coronary care.

“The human brain has totally blocked out what happened in between.”

He added: “A lot of people ask me if I saw anything, and no, I did not see anything. No bright lights, nothing like that whatsoever.

“It’s a case of not knowing what’s out there – but I don’t mind about that, as long as I’m fit and healthy.”

Doctors managed to unblock one of the 61-year-old’s arteries at Frankston Hospital and he was fitted with a pacemaker.

Alistair returned home after 12 days in hospital and says that his near-death experience has given him a completely different approach to life.

After his brush with death, Alistair reduced the number of hours he works in order to see friends and family more. He also eats more healthily and does more exercise too.

Near death experiences are a topic of scientific fascination, particularly to one researcher Dr Steven Laureys, a neurologist at the Centre Hospitalier Universitaire de Liège in Belgium.

According to Laureys, near death experiences feel ‘even more real than real’ and he says its ‘the dysfunctional brain which causes the phenomena’.

His research also suggests that some people have a very vivid experience.

A study has revealed what could happen in the final moments before death.

However, the patient sadly suffered a fatal heart attack while the team were conducting a neurological reading, which revealed an unexpected insight into what can happen when a person dies.

The recording – which is the first ever recording of a dying brain – indicated that in the 30 seconds before and after death, brainwaves followed patterns similar to dreaming or recalling memories.

Scientists think the findings could suggest a ‘flashback’ before the end of life.

“If I were to jump to the philosophical realm, I would speculate that if the brain did a flashback, it would probably like to remind you of good things, rather than the bad things.”

“But what’s memorable would be different for every person.”

Dr Zemmar added that the activity continued for 30 seconds after the patient’s heart stopped beating.

“This could possibly be a last recall of memories that we’ve experienced in life, and they replay through our brain in the last seconds before we die,” he said.

The study also raises questions about the point of death and whether it occurs when the heart stop beating, or when the brain activity ends.

Dr Zemmar explained that more studies would need to be conducted, adding that conclusions cannot be drawn from just one.

“I never felt comfortable to report one case,” he said.

However, one study from 2013 also offered interesting findings. In the study, US scientists looked at brainwave activity in healthy rats at the point of death, until 30 seconds after death.

Dr Zemmar described the similarities between his study and the research conducted in 2013 as ‘astonishing’.

“I think there’s something mystical and spiritual about this whole near-death experience,” he said.

“And findings like this – it’s a moment that scientists lives for.”