Death is a universal truth for us. If you take birth in this universe then one day you have to die. But what happens after death? is there an afterlife? Nobody actually knows the answer it’s a veiled secret only known to you when the end comes.
However, scientists able to discover some amazing things that happen inside the brain after death. Scientists believe this research will able to answer some mysterious closing moments of consciousness. Before discussing further let’s understand first what is the actual meaning of death.
What is death?
Over a long time, death is defined in different ways. Death, in a medical sense, is when the heart stops beating and cuts off blood supply to the brain. This means the brain’s functions also stop and can no longer keep the body alive.
But a few hundred years back, if someone appears to die, then people used to call the local priests rather then the doctor for help. The priest checks the outward reactions of the persons by holding a feather above his nose to check the sign of breath. This process was not superior to identify a person’s death all time, In fact, many times people are buried alive.
In the 18th century, it was the first time people started checking heartbeat to found out the existence of life. But soon they realized it’s not enough. As time went on, medical science creates a list of host devices that can keep anyone alive even if the there respiratory or circulatory system fails. In the recent few years medical technology also mastery the technologies which can keep our body bodies alive even after the brain is dead.
From history, we able to understand, until 19th-century people believe death is defined by stopping the heart when medical technology was not that advanced. But as we can see now with the help of host devices people can even live with the heart stopped. Advancing in technology always changes the definition of death. I believe in the near future the definition will change again, maybe this advancement will lead us a longer life than now.
What happens if someone dies of a heart attack or cardiac arrest?
You may be heard those terms many times in recent years. Our modern lifestyle and eating junk food rising the chance of “cardiac arrest” and “heart attack”. Unknowingly people frequently use those terms interchangeably, but according to American Heart Association(AHA), those conditions are not identical.
In the case of a heart attack, a blocked artery prevents blood from reaching a portion of the heart, which can cause that section to die through the heart continues to beat.
And in case of cardiac arrest, the electrical signals driving the heart’s pumping action are disrupted, the heart ceases beating and death shortly follows.
In many cases when someone died and been brought back to life claim that they saw a light at the end of a tunnel. The first time I hear this, my first expression was “is it actually true?“. I think you too have the same question.
Dr. Sam Parnia and her team from New York University Langone School Medine also had the same question. They started there journey to find the answer by studying Europe and US people who have died because of cardiac arrest and come back to life. In an interview with Live Science, he told those dead people able to see and understand their surroundings while according to medical science they are dead.
“They’ll describe watching doctors and nurses working and they’ll describe having awareness of full conversations, of visual things that were going on, that would otherwise not be known to them,”
Later medical staffs also verified that those details and confirmed their patients remember the details accurately.
More then thousands of people who have approached death, all of them reported a bright door, vivid colors which they never saw, life flashbacks, and detachment from the body, some of them also report encounters with spirits. Those experiences are called Near Death Experiences which are widely known as phenomena but according to the medical and scientific community, those are merely hallucinatory or illusory in nature.
In March 2017, doctors of a Canadian hospital was trying to record the persistent brain activity of the four-terminal patients after they turned off their life support machines. This unit discovered that one person was aware of more than 10 minutes. You can see the brain scans of those patients below.
In those scans, the moment of clinical death shown as time 0, and the yellow activity is a persistent brain activity that is what we are looking for in those scans. As you can see three out of four patients the activity faded away before the heart stopped beating – as much as 10 minutes before clinical death, in the case of patient #2. But due to some unidentified reason, In the case of patient #4, the scan shows evidence of delta wave bursts for 10 minutes and 38 seconds after the heart had stopped.
This is not the first time brain activity has been recorded after death. Previously the AWARE(Awareness During Resuscitation) study observed 2,060 patients associated with cardiac arrest. Among those patients, only 330 survived and 140 were able to recall their memories of the event. The researchers found that only 39% of those people had some awareness at the time when their hearts stopped beating. According to lead Dr. Parnia, some of those patients have mental activity during the cardiac arrest but due to brain injury or the use of sedative drugs, they lose their memories after recovery.
A trajectory of cell death inside the brain
When someone dies, their brain does not die instantly as we think. The thinking part of the brain which is known as the cerebral cortex slows down instantly within 2 to 20 seconds and flatlines which means no brainwaves will be visible on an electric monitor. This will start a chain reaction on a cellular level that eventually results in the death of all brain cells. According to Dr. Parnia, this can take hours after the heart has been stopped.
Dr. Parnia and his team study the human mind and try to found out how consciousness is related to the context of death. They tried to understand whether consciousness becomes annihilated or it continues after someone has died for some period of time.
They discovered that performing Cardiopulmonary Resuscitation(CPR) send only 15% of blood what the brain requires to function normally. This amount of blood is enough to slow down the brain cell’s death trajectory, but it is not enough to kick-start the brain into its normal working again. This is the reason why reflexes don’t resume during CPR.
Death and beyond
For a long time, people are curious about what happens after death? Many of us believe in the afterlife, means the life after death, they think we have another life after death. To found out this answer a largest study is conducted in a number of peoples in Europe and the United States. The first and most important problem they face is finding more accurate methods of brain monitoring. At the time of resuscitation, brain realises very low delta waves which are hard to track.
The same group of researchers also studying the qualitative nature of the human experience for example “love”. They are trying to understand what is the universal experience of people when they go through death. Although in the current study unable to found any specific details, any patients had different memories about specific topics.
20% of the patients said they felt peaceful while one-third of them reported, the time had either speed up for them or slowed down. Some of them had tranquil experience and saw animals or bright lights around them, whereas others felt fear and even encounter the feeling of being dragged through the deep water.
Interestingly, 13% of them are able to recall everything in the hospital room, they also felt separated from their bodies. One 57-year-old man from Southampton recalled leaving his body entirely and watching the actions of the nursing staff from the corner of the room. He was also able to recall two beeps from a machine that only makes noise every three minutes. The man has died for three minutes after that medical staff able to kick-start this man’s heart again.
Only 2% of those patients are reported to recall hearing or seeing actual events. The details of those events were so consistent and similar that it’s impossible to neglect them.
Dr. David Wilde, a psychologist at Nottingham Trent University, is checking each case data carefully and compiling the data trying to found out a common link between those out of body experiences. Most of those studies are taking place before 10 or 20 years ago which makes the work a lot of validity, most of the data are lost or they do not have advanced equipment as now. But Dr. David Wilde is very hopeful about this study and believes this study can help to shine a scientific lens on death.
I’ll eager to know your view about an afterlife, don’t forget to tell us in comments.