This article aims to provide a scientific explanation of the death experience. This is particularly intriguing in the research field because the brain continues to function even when the heart ceases to beat. Researchers commonly define clinical death as the state in which our hearts cease to function, but recent research has shifted their perspective due to the death experience. In recent years, the idea has gained traction, with reports revealing a 30-second period of brain activity following death. This topic requires further investigation and research to gain a deeper understanding of the after-life experience. This is the bitter reality: every individual will die, but what happens after this life?
A Study in University of Louisville
As a rather beautiful story unfolded, a University of Louisville neurosurgeon studied the rare recording. There are very specific brain wave patterns that occur in the brain. In studies of healthy humans, brain activity recordings have shown active gamma waves as a person looks at pictures of memorable life events, such as a wedding or the birth of a child. These same waves appeared in abundance in the dying patient and remained present for 30 seconds after death. The dying patient’s brain wave patterns appear to correlate with those of those who have had a near-death experience. Examining near-death experiences reveals a fairly consistent description from those who have experienced them. A member of a memory flashback recalls that the finding has sparked both scientific and spiritual debate. The biggest question, in my opinion, is whether we should perceive nerve cells firing and brainwaves as active or as having a functional meaning, and whether we should be able to perceive and recall these memories effectively.
The Concept and Books Emerge
In the late 20th century, near-death experiences (NDEs) gained public attention thanks to the efforts of medical professionals and psychologists, notably Raymond Moody. Moody popularized the term “near-death experience” in his bestselling book, Life after Life, published in 1975. Another influential figure in this field is Bruce M. Greyson, who co-authored the aforementioned study and also published The Handbook of Near-Death Experiences in 2009. By observing recurring patterns in individuals’ accounts of near-death experiences, these researchers transformed a phenomenon previously criticized as confabulation or disregarded as delusional hallucinations (historical death bed visions) into a field of scientific investigation. The Tibetan Book of the Dead provides guidance on how to handle the matter. This text elucidates the means by which one can attain liberation during the moment of death and fully realize their potential as spiritually enlightened beings, akin to Buddhas.
Researchers Work from a Biological Perspective
When the heart stops, the same process occurs. The processes of death and resuscitation are essentially the same. Sometimes, even up to an hour into the process, the researchers observed the same brain waves occurring in individuals who appeared to be unconscious. However, the researchers discovered a biological marker of lucid consciousness in their brains, despite their apparent lack of awareness of their surroundings. They seem to be completely unresponsive. Is that possible? These experiences of seeing a bright light and a god-like being make it possible that they were only in a dream state at the time.
Consciousness Is Unique Only At Depth at the Time of Death
Consciousness is unique only at depth; for example, why should it be at death? Our brains contain mechanisms that break down certain aspects of our consciousness. We can carry out our daily activities, but upon death, the cessation of brain blood flow eliminates these brain mechanisms, granting individuals access to previously dormant parts of their brain. This, in turn, opens up new realms of reality, encompassing their entire consciousness, akin to a sudden emergence of an iceberg. They can recollect every encounter in their lives, and crucially, they assess it according to morality and ethics.
The Beta, Alpha, Theta, and Delta Waves Function in Our Body
| Beta (β) | 12–35 Hz | Anxiety dominant, active, external attention, relaxed |
| Alpha (α) | 8–12 Hz | Very relaxed, passive attention |
| Theta (θ) | 4–8 Hz | Deeply relaxed, inward focused |
| Delta (δ) | 0.5–4 Hz | Sleep |
 Neural oscillations in healthy individuals play a crucial role in organizing the timing of information processing in perception, consciousness, and memory across different states of consciousness, such as wakefulness, dreaming, and meditation. Scientists have found that there is more activity in the thalamocortical area, more gamma power, and long-range gamma synchronization (> 35 Hz) in conscious perception. Alpha-band oscillations are the primary frequency range in the human brain and play a crucial role in information processing, particularly in the visual cortex. They likely exert an inhibitory effect on underutilized cortical areas. Furthermore, scientists have proposed that delta band activity serves a comparable inhibitory role by potentially suppressing networks that are not necessary for task completion. Theta rhythms are crucial for memory retrieval, especially in tasks involving verbal and spatial memory, as well as during meditation. The complex interaction between these bands and the synchronization of different frequencies are responsible for long-distance communication between neurons, as well as the processes of perception and memory recall.
Gamma oscillations synchronize with Alpha and Theta waves
After cardiac arrest, there was a discovery of heightened connections between the cortex and the heart, as well as increased connections between the front and back of the brain in rodents. Additionally, there was a synchronization between gamma oscillations and alpha and theta waves, as well as an increase in oscillatory activity in the gamma frequency range within the first 30 seconds. Cardiac arrest, asphyxia, and hypercapnia promptly elicit a sudden increase in gamma oscillations. In real-life acute settings, we have not observed the neurophysiological processes that occur in the human brain during death. This is due to the rarity of capturing complete standard EEG activity during the transitional phase to death.
The Story of the Patient (Gamma Range Was Higher)
The patient exhibited a transient elevation in gamma power upon cessation of bilateral hemispheric activity, which subsequently declined referred to as cardiac arrest. Simply put, the EEG from this patient did not show the expected rise in absolute gamma activity following cardiac arrest, which was believed to be associated with the life review experience. Instead, it revealed a decrease in absolute gamma waves after cardiac arrest. The gamma component exhibited a higher proportion relative to the alpha, beta, and delta components. After cardiac arrest, all brain activity ceased. However, the decline in brainwaves in the alpha, beta, and delta bands was faster compared to the gamma band. As a result, the proportion of remaining activity in the gamma range was higher relative to the other frequencies.
There Are Differences between Clinical Death and Brain Death
Clinical death is diagnosed when a subject has no heart function, has no more reflexes, does not breathe, and does not respond to repeated well-defined clinical tests, e.g., of muscular activation. With the improved medical technology of cardiopulmonary resuscitation, it is now possible to overcome clinical death, i.e., to restore cardiac function and breathing after an arrest of 10–15 minutes or longer. Modern techniques even allow the induction of clinical death or artificial coma in order to save the lives of severely injured trauma victims while trying to repair their injuries. Therefore, one has to understand that clinical death is not death, but brain death implies the termination of a human’s life.
Emergence of the Concept of Brain Death
The concept of brain death first emerged in the 1950s, driven by advances in critical care medicine such as cardiopulmonary resuscitation and the development of mechanical ventilation. The diagnostic criteria for assessing brain death in addition to clinical death may differ among countries; however, all include measurements of possible brain activity, at least via EEGs. Thus, with technological progress, the concept of death has evolved from an ancient cardiorespiratory-centered diagnosis to a neuro-centered diagnosis. Nearly 50 years ago, the first clinical/neurological definition of brain death reported no recovery from brain death in patients fulfilling its criteria.
A Recent Study Showed Result
More recently, we were able to record the intracortical activity of dying patients due to cardiac arrest (clinical death). They reported a drastic drop in the brain’s arterial pressure just after cardiac arrest. At the same time, a sharp decline in neural activity appeared throughout the brain. This non-spreading depression was associated with neuronal hyperpolarization. This activity decrease developed during the steep fall of brain oxygenation and may correspond to the cellular energy-saving necessary to preserve brain cell integrity. It lasted 2 to 3 minutes. With a latency of up to 4–5 min, a phase of activity of chained neurons followed, spreading toward neighboring neurons throughout the brain for about 10 min (spreading depolarization). Adequate resuscitation procedures could still reverse the toxic processes that began with the onset of spreading depolarization in the neurons.
This article aims to educate the public about a new concept in academia concerning the function of the brain after death. I hope this article will provide valuable information and knowledge about the concept of the death experience.
Dr. Abid Hussain Nawaz
References
Learned a lot of new things from your writings, Thank you Dr. Abid
it’s very interesting and attention capturing