Doctors have shared the important sign that someone is close to death - and it involves one of their senses being lost.
What happens around the time of death is a hard topic to gain knowledge about, especially surrounding how the person is feeling and the kind of things that they experience.
This is because the patient is often too weak or drowsy to explain how they feel, and instead doctors have to rely on the accounts of those who are in the room with them, such as family and friends.
The Mirror reports that historically, death was something that happened very quickly - before modern medicines allowed dying patients to live longer.
For most people who die in this way, there's a sudden change that takes place around the last few days of life - known as "active dying".
James Hallenbeck, a palliative-care specialist at Stanford University, said people tend to lose their senses and desires in a certain order.
Writing in Palliative Care Perspectives, his guide to palliative care for physicians, he said: “First hunger and then thirst are lost. Speech is lost next, followed by vision.
"The last senses to go are usually hearing and touch.”
Many people also believe that there's a bright light that's often seen right before a patient passes away.
David Hovda, the director of the UCLA Brain Injury Research Center, said the brain "starts to sacrifice areas which are less critical to survival", reports The Atlantic.
“As the brain begins to change and start to die, different parts become excited, and one of the parts that becomes excited is the visual system - and so that’s where people begin to see light," he said.
These heightened senses seem to support what experts know about how the brain responds to death.
Jimo Borjigin, a neuroscientist at the University of Michigan, noticed that just before animals die, neurochemicals in the brain suddenly surge.
Scientists already knew that brain neurons continue to fire after death, but now they were releasing large amounts of new chemicals.
Borjigin said cardiac arrest survivors describe an "amazing experience in their brain" in which they see lights and everything is "realer than real", which she puts down to this release.
In the final hours, patients will have stopped eating and drinking, and lost vision, before closing their eyes and appearing to sleep.
Hallenbeck said: “From this point on … we can only infer what is actually happening.
"My impression is that this is not a coma, a state of unconsciousness, as many families and clinicians think, but something like a dream state.”
But it's hard to say when exactly it kicks in.
“It’s like a storm coming in,” he continued.
“The waves started coming up. But you can never say, well, when did the waves start coming up?…The waves get higher and higher, and eventually, they carry the person out to sea.”
Don't miss the latest news from around Scotland and beyond - sign up to our daily newsletter here.
