Father Tadeusz Pacholczyk, Ph.D.
Near-death experiences (NDEs) are a complex set of phenomena that often include reports of leaving one’s body, seeing one’s body from outside or above, passing through a tunnel of light, seeing various forms of illumination, experiencing the presence of deceased relatives and friends, and even sensing the presence of angels or divine beings. Between 12 and 15 percent of resuscitated heart attack patients report NDEs.
Spiritual interpretations and religious overtones are sometimes used in discussions of these experiences, and some commentators have claimed that “near-death experiences are certainly clear and obvious evidence of a transphysical soul” that we can use “to obtain information about the afterlife.” However, such strong claims need further substantiation, even if they generate heated debate.
To be clear, near-death experiences are not cases where a person actually dies and then comes back from the dead to tell the story. If a person were to die and come back to life, there would have to be a supernatural explanation and cause. Human corpses do not come back to life, aside from the rare miraculous events surrounding the deaths of Jesus, Lazarus, Jairus’ daughter, the widow’s son, and Nain, as we see in the Gospels.
The death of a human being is always associated with the key concept of irreversibility, that is, the irreversible cessation of circulatory and respiratory functions or the irreversible cessation of all functions of the entire brain, including the brain stem, as explained in the 1981 guidelines of the American Medical Association. Near-death experiences involve situations that are reversible. They can be caused by physiological phenomena that occur when the human brain is subjected to various stressors, such as lack of oxygen, and not by any truly supernatural phenomena.
Although supernatural forces could theoretically cause a near-death experience, explanatory models should not be multiplied beyond what is necessary, as “Occam’s razor” recommends. The wisdom of the Church in evaluating such matters is that we should generally favor a natural explanation for a phenomenon unless the evidence for a supernatural explanation becomes truly convincing or overwhelming.
Rather than assuming a supernatural explanation for near-death experiences, scientists have considered alternative explanations by studying stressful near-death situations and their effects on brain function.
A 2023 Scientific American The article describes how researchers “analyzed EEG data from four comatose patients before and after their ventilators were turned off. When the patients’ brains were deprived of oxygen, two of them showed an unexpected increase in gamma activity, a type of high-frequency wave associated with memory formation and information integration.”
This suggests that even in situations of severe hypoxia, certain brain functions may be active, at least briefly, in ways that could continue to impair thinking and cognition.
Dr. Kevin Nelson, a researcher who has studied near-death experiences in depth, notes, “One of the most common causes of near-death experiences is fainting,” which can cause a feeling of separation from one’s body or a feeling of euphoria. Researchers have also reported that a restriction of oxygen to the eye can sometimes cause tunnel vision.
Others argue that hallucinatory mechanisms of the central nervous system may contribute to near-death experiences. Well-known neurologist Dr. Oliver Sacks points out that migraine headaches can produce illusions or hallucinations, which sufferers often describe as pulsating lights, shimmering illumination, or fields of brightness.
Sacks has also described the work of Swiss neuroscientist Dr. Olaf Blanke, who was able to produce a hallucination, “a ‘shadow person’ in a patient by electrically stimulating her left temporoparietal junction. ‘When the woman was lying down,’ Sacks reported, ‘a slight stimulation of this area gave her the impression that someone was behind her; a stronger stimulation enabled her to identify the (person) as young but of indeterminate sex.'”
Near-death experiences can also resemble drug-induced experiences, and many have noted the similarity of near-death experience reports to essays written by conscious drug users about their experiments and trips while using drugs such as mushrooms, cannabis, LSD, ayahuasca, etc.
Sacks also makes the important observation that hallucinations seem so real because “they activate exactly the same systems in the brain as actual perceptions.” When someone hallucinates a face, the fusiform face area, which is normally used to perceive and identify faces in the environment, is activated. When someone hallucinates a voice, the auditory pathways are stimulated. It seems reasonable to assume that near-death experiences rely on similar mechanisms.
Sacks also raises the possibility that near-death experiences do not occur when the person is actually suffering from a lack of blood flow to the brain or is trapped in a deep coma, but rather when they awaken from the coma and their cerebral cortex begins to regain function.
Since the cause of a person’s near-death experience is difficult to determine, a certain degree of caution must be exercised when interpreting such experiences.
The most authoritative source of information about life after death is and remains the one who came from heaven, redeemed us through his suffering, death and resurrection, and invites us to follow him into eternal life.
Rev. Tadeusz Pacholczyk, Ph.D., received his PhD in neuroscience from Yale University and completed postdoctoral work at Harvard University. He is a priest of the Diocese of Fall River, MA, and serves as chief ethicist at the National Catholic Bioethics Center in Philadelphia. See www.ncbcenter.org and www.fathertad.com.
