Dr. Michael Sabom is a cardiologist whose book entitled Light and Death includes a detailed medical and scientific analysis of an amazing near-death experience of a woman named Pam Reynolds. She underwent a rare operation to remove a giant basilar artery aneurysm in her brain that threatened her life. The size and location of the aneurysm, however, precluded its safe removal using the standard neuro-surgical techniques. She was referred to a doctor who had pioneered a daring surgical procedure known as hypothermic cardiac arrest. It allowed Pam's aneurysm to be excised with a reasonable chance of success. This operation, nicknamed "standstill" by the doctors who perform it, required that Pam's body temperature be lowered to 60 degrees, her heartbeat and breathing stopped,
her brain waves flattened, and the blood drained from her head. In everyday terms, she was put to death. After removing the aneurysm, she was restored to life. During the time that Pam was in standstill, she experienced a NDE. Her remarkably detailed veridical out-of-body observations during her surgery were later verified to be true. Her case is considered to be one of the strongest cases of veridical (i.e., verified) evidence in NDE research because of her ability to describe the unique surgical instruments, the surgical procedures used on her, and her ability to describe in detail these events while she was clinically brain dead.
You theorize that NDEs are produced by brain chemistry. But, Dr. Peter Fenwick, a neuropsychiatrist and the leading authority in Britain concerning NDEs, believes that these theories fall far short of the facts. In the documentary, "Into the Unknown: Strange But True," Dr. Fenwick describes the state of the brain during a NDE:
"The brain isn't functioning. It's not there. It's destroyed. It's abnormal. But, yet, it can produce these very clear experiences ... an unconscious state is when the brain ceases to function. For example, if you faint, you fall to the floor, you don't know what's happening and the brain isn't working. The memory systems are particularly sensitive to unconsciousness. So, you won't remember anything. But, yet, after one of these experiences [a NDE], you come out with clear, lucid memories ... This is a real puzzle for science. I have not yet seen any good scientific explanation which can explain that fact."
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NDE's while brain dead)