Neurobiologische Erklärungsmodelle für Nahtoderlebnisse

Subtitle: Neurobiological theories on near-death experiences

Article type: Research Article

Authors: Kasten, Erich | Geier, Jens

Affiliations: Abteilung für Medizinische Psychologie und Medizinische Soziologie, Georg-August-Universität Göttingen

Note: [] Korrespondenzadresse: Prof. Dr. Erich Kasten, Institut für Medizinische Psychologie, Univeristät zu Lübeck, Ratzeburger Allee 160, Haus 73, 23538 Lübeck. Tel.: (0451) 500 6094, E-mail: EriKasten@aol.com

Abstract: Although there are studies on near-death experiences since the end of the 19th century, this topic found a lively interest after the publication of the book "Life After Life" (1975) by the American physician Raymond A. Moody, who developed – based on reports of reanimated patients – several characteristic sequences of the dying process. Subsequently a rising number of mainly interview-based near-death studies were initiated. Due to the lack of scientific evidence those studies were accused of being suggestive and ignoring narratives which did not fit into Moody's well-established phases. In the last 30 years several scientists disputed, if and how these neardeath experiences can be explained on a neurobiological basis. It seems that during the process of dying a cascade proceeds in which the brain releases huge amounts of neuro-transmitters leading to drug-like experiences. At this point a disinhibition of memory contents arises which leads to a kind of kaleidoscope-like retrospections. The frequently reported out-of-body experiences are not only associated with the process of dying; likewise this phenomenon occurred in neurological diseases and schizophrenia. Stimulation of a specific area of the brain (temporo-parietal junction) leads to these out-of-body experiences. Experiments investigating whether people with out-of-body experiences – i. e. reports of patients who had the feeling of hovering above their own body in the operating room – can really detect objects which they were unable to see from a lying position, showed no evidence. Near-death experiences can be simulated by Ketamine, which is primarily used for the induction and maintenance of general anesthesia. Responsible for the profound religious feeling, which many dying people mentioned, is the so-called "God module", an anatomical structure in the temporal lobe. Near-death experiences emerge not only in dying people, but can be triggered by several other events. Nowadays, the stages of Moody are seen as an artifact, supposedly based on extremely intensive hallucinations.

Keywords: Near-death, near-death-experiences, out-of-body-experiences, Ketamine, stages of dying

Journal: Zeitschrift für Medizinische Psychologie, vol. 18, no. 1, pp. 13-27, 2009