“It’s only the brain shutting down.”

Despite decades of theorizing, the most comprehensive attempt to explain the NDE in reductionist terms remains that of psychologist Susan Blackmore (1993), who argues that the NDE is the hallucinatory result of a combination of neurophysiological and psychological events occurring in the dying brain. Some of her key claims are that the feelings of joy and peace are the result of natural opiates being released in the brain as it shuts down; the tunnel, light, and sound are a result of anoxia; the life review is due to “seizures in the temporal lobe and limbic system where memories are organized”; and the OBE is the brain’s attempt to “model reality.” All this is combined with “prior knowledge, fantasy, lucky guesses and the remaining operating senses of hearing and touch.” The intense reality of the NDE is allegedly caused by the brain’s attempt to retain the disintegrating construct that is the personality and consciousness.

Blackmore also sees the tunnel experience as “neural noise” caused by a malfunctioning visual cortex, resulting in impressions of light growing increasingly larger and the sensation of moving through a dark tunnel towards that light. This is also problematic. As a supposed neurophysiological occurrence, the “tunnel” should be universal, though cross-cultural evidence shows that this is not the case. It is not reported in Indian NDEs or in small-scale societies, and indeed the tunnel per se is actually uncommon even in Western cases

 As a supposed neurophysiological occurrence, the “tunnel” should be universal, though cross-cultural evidence shows that this is not the case.

Individual and cultural variations between NDEs should not occur if the experience is caused by a neurophysiological process, and this creates a serious problem for “all-in-the-brain” explanations such as Blackmore’s 

Nor do reductionist theories explain cases of individuals accurately describing events they claim to have witnessed during OBEs. 

Perhaps the most famous such case is that of Pam Reynolds (Sabom 1998), who reported an OBE she had during brain surgery, while clinically dead, with her body temperature lowered and her head drained of blood for the operation. She claimed to have witnessed medical procedures from a vantage point outside her body, and accurately described them upon resuscitation, including details such as the design of the bone saw which cut into her skull and the pitch of the sound it made.

A recent international experiment led by resuscitation expert Sam Parnia, the AWARE study (AWAreness during REsuscitation), has apparently confirmed that consciousness can persist when no brain activity is detectable, actually during the period of clinical death prior to successful resuscitation. This was widely believed to be medically impossible, and has profound implications for the notion that consciousness can survive physical death.

 The investigation of NDEs in the blind is another important area of research, for they report visual perceptions during the experience. Dozens of such cases have been published, including from individuals who have been blind since birth. This is in striking contrast to dreams of the blind, which are not visual

Some children report encounters with deceased relatives they never knew, and are able to either accurately describe them or identify them from photographs. Similar cases are also reported by adults who describe encountering the spirit of an individual whose recent death was unknown to them.