According to a new study published by the University of Western Ontario, brain activity may continue for more than 10 minutes after clinical death.
Brain activity continues for more than 10 minutes after deathThe Canadian study observed that the brain activity in patients in the intensive care unit continuing to work even after they were declared clinically dead.
Doctors confirmed patient death through a range of the normal observations, including the absence of a pulse and nonreactive pupils. However, tests showed that the patients’ brain appeared to keep working – experiencing the same kind of brain waves that are seen during deep sleep.
In the study, doctors recorded “single delta wave bursts persisted following the cessation of both the cardiac rhythm and arterial blood pressure (ABP)”.
Only one of the four people studied showed some long-lasting and mysterious brain activity, while in the other three patients, the activity was close to dying off before their last heartbeat. However, the scientists noted that all of their brains behaved slightly differently in the minutes after death.
Two previous studies published in 2016 found that 1,000 genes were still functioning in the patients several days after death. Interestingly, the activity of these genes had ramped up after death, rather than slowing down.
Awareness continues for up to three minutes after clinical deathNear-death experience has always been a questioned that intrigued scientists. A study launched in 2008 which involved more than 2,000 patients from Austria, US and the UK found that awareness continues for up to three minutes after clinical death has been pronounced.
Among the patients who survived cardiac arrest, almost 40% of them could recall some form of awareness after being clinically dead.
An outer-body experience was recounted by a 57-year old man where he could tell accurately what went on after he ‘died’. While sceptics could have dismissed this experience as bordering on new age spiritualism, his detailed recollections of visual awareness were consistent with verified events.
Lead researcher Dr Sam Parnia said, "This is significant, since it has often been assumed that experiences in relation to death are likely hallucinations or illusions occurring either before the heart stops or after the heart has been successfully restarted, but not an experience corresponding with 'real' events when the heart isn't beating.”
"In this case, consciousness and awareness appeared to occur during a three-minute period when there was no heartbeat.”
He added, "Contrary to perception, death is not a specific moment but a potentially reversible process that occurs after any severe illness or accident causes the heart, lungs and brain to cease functioning.
"If attempts are made to reverse this process, it is referred to as 'cardiac arrest'; however, if these attempts do not succeed, it is called ‘death’."
Findings are slowly starting to show that the pulse may not signal the cessation of life, which raises issues on the removal of organs from donors who were supposedly pronounced as dead. The authors of the Canadian study highlight the ethical implications concerning the appropriate time to do so, suggesting a need for further investigation. MIMS
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