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Let's talk about death

Tibetan Buddhists have a daily mantra. Death is real, it comes without warning, this body will be a corpse. Here in the secular west, we consider regular contemplation of death to be morbid.

Death is a vast mystery, but there are two things we can definitely say about it. It's inevitable and its timing is unknown. Unfortunately we seize on the latter as an excuse to put off facing death directly. Yet the longer we postpone facing death, the more we fear it.

According to mystics and sages from all the great wisdom traditions, denial of death deprives our life of true meaning. Far better to make friends with dying by reflecting on what death might actually feel like and what happens to the mind and body after you die.

Dr Katherine Clark is a staff specialist in palliative care at Royal Prince Alfred Hospital, Sydney. She knows all about the common symptoms experienced by people on their deathbed. "Of course, each person's death is unique," she says. "So you might see only some of these symptoms or none of them."

According to Clark, a person in the last stages of life will typically sleep more. Even so, loved ones are encouraged to keep talking to them. "There's research based on electroencephalograms (EEGs) of people's brain waves that indicates hearing is the last sense to go."

Breathing patterns change too. A dying person may take shallow and quick breaths or slow and laboured ones. They may also make gurgling noises, sometimes referred to as the "death rattle". In fact the sound is caused by air passing through mucus pooled in the person's pharynx, which they're unable to shift through coughing.

Equally distressing to onlookers is Cheyne-Stokes breathing. This is characterised by periods of up to 45 seconds of no breathing at all, followed by deeper and more frequent respirations. It occurs as vital organs are deprived of oxygen and waste products build up.

Hallucinations, agitation, loss of appetite, changes in bowel and bladder function as well as in skin temperature and colour are experienced as oxygen flow to the brain decreases, vital organs shut down, muscles relax and blood moves away from the extremities.

Finally there's the moment of death itself, when the heart stops beating and breathing ceases. Death was once defined as meeting these criteria, but the development of cardiopulmonary resuscitation (CPR) and prompt defibrillation forced a rethink. Doctors now turn to 'brain death' where a definition of death is required.

There is no place on earth where death cannot find us, even if we constantly twist out heads about in all directions as in a dubious and suspect land … If there were any way of sheltering from death's blows, I am not the man to recoil from it … But it is madness to think that you can succeed …

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Brain death

Brain function is reflected in our level of consciousness. According to Associate Professor Leo Davies, a neurologist at Prince Alfred Hospital, Sydney, "consciousness implies being aware of your existence and we can only assess this by someone being able to respond to sensory input with motor output. So if someone talks to you or sticks you with a pin, you react."

Consciousness, memory and thought are properties of the upper brain (neocortex). The lower brain (brain stem) controls automatic functions such as breathing, blood pressure and temperature control.

Loss of consciousness is a prerequisite for the diagnosis of brain death but loss of neocortical function alone does not constitute brain death. "That's because the body can have quite complex motor responses when only the brain stem is functioning" says Davies.

Therefore to be legally brain dead, the brain stem must have stopped working. Although the heart will continue to pump, breathing will stop without brain stem input.

"And as the brain stem is the last bit of the brain to die, death of this structure implies global brain death," says Davies. "You can withdraw care because now all you're dealing with is a lump of flesh."

Sometimes the terms 'brain death', 'coma' and 'persistent vegetative state' are used interchangeably. In fact, they describe vastly different conditions.

A person in a coma is unconscious and their eyes are closed. A person in a persistent vegetative state is also unconscious but their eyes are open and may rove giving the 'appearance' of wakefulness. In both cases the brain is working, albeit at a very rudimentary level.

A flat EEG is one of various tests doctors may use to establish the absence of brain activity.

At times during anaesthesia, cardiac arrest or profound coma, brain electrical activity may cease for a time before being restored. Intriguingly some of the "flat liners" who come back report there's life after death.

Men come and they go and they trot and they dance, and never a word about death. All well and good. Yet when death does come — to them, their wives, their children, their friends — catching them unawares and unprepared, then what storms of passion overwhelm them, what cries, what fury, what despair! …

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Near death experiences

Their brief journey to the other side typically consists of feeling peaceful, floating out of their body and observing it from above, moving through a tunnel into a bright light, meeting loved ones and seeing their life pass before their eyes.

So is this proof of an afterlife?

Susan Blackmore is considered one of the world's leading authorities on the subject. She writes on her website: "NDEs provide no evidence for life after death, and we can best understand them by looking at neurochemistry, physiology, and psychology."

Blackmore argues the peaceful feelings are probably produced by endorphins that are released under stress.

Other effects are due to disorganised firing of neural cells in different parts of the brain set off by lack of oxygen or by stress and fear.

"So for example, the life review happens when memory circuits are randomly activated in the temporal lobe, lights and tunnels when the visual cortex is randomly firing."

But Blackmore agrees that if it someone proved NDEs take place when people are actually clinically dead, "our view of the mind/body relationship would radically change."

Dr Sam Parnia at the University of Southhampton, England, and neuropsychiatrist Dr Peter Fenwick aim to try.

They are developing a prototype of a device that generates images that are only visible from the ceiling, where those who experience out-of-body experiences claim to watch their resuscitation. They will use this in combination with a portable brain monitor that measures electrical activity, in heart attack victims.

"The key thing is to show that people have an OBE at the same time global brain function has ceased, " says Parnia.

"If this can be done in a large scale study, it will indicate that consciousness and the mindt may be able to function without a working brain."

To begin depriving death of its greatest advantage over us, let us adopt a way clean contrary to that common one; let us deprive death of its strangeness, let us frequent it, let us get used to it; let us have nothing more often in mind that death … We do not know where death awaits us: so let us wait for it everywhere. To practice death is to practice freedom. A man who has learned how to die has unlearned how to be a slave. Michel de Montaigne 1533-1592

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Flesh and bones

Mystery may surround the nature of consciousness. But there's no mistaking our corporeal reality. Soon after death, a corpse starts decaying. And if conditions are optimal — it's hot, humid and there are lots of flies — within weeks the body may be fully skeletonised.

Decomposition consists of a number of stages. "First, there's muscle stiffening, cooling of the body and post mortem lividity," explains Professor Jo Duflou, Chief Forensic Pathologist at the Department of Forensic Medicine, Glebe.

These phenomena are otherwise known as rigor mortis, algor mortis and livor mortis.

Rigor mortis results when two major proteins that lock and unlock during muscle contraction and relaxation deteriorate and fuse.

Algor mortis occurs because the body is no longer metabolising and producing heat.

And livor mortis is the settling of blood as a result of the action of gravity into the dependent parts of the body. "So if you're hanging suspended by the neck, the skin of your legs and arms will appear darker," says Duflou.

Interestingly, lividity fixes between 6—12 hours, so there's no way to try and fool police by moving the body after that time.

Insects also offer clues if there's been foul play, especially flies which are attracted to bodies from the moment of death. Forensic entomologists may be able to tell when and where a victim died by the type, age and level of infestation of maggots.

Meanwhile other post mortem changes are starting to take place.

Bacteria that before death fed on the contents of the intestine digest the intestine itself then move to digest other parts of the body.

Individual cells break down due to the action of enzymes and other chemicals released by the cells.

And gas builds up, resulting from the activity of multiplying bacteria. This in turn creates pressure within the body and forces fluids out of the cells and blood vessels into the body cavity, intensifying the rate of decay. By now the body looks and stinks like rotten meat.

Insects and animals take care of the rest. Eventually all that's left is a dry and brittle skeleton, a potent reminder of the fate that awaits all of us.

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