outline the features of the NDE. Internet Infidels paper editor and commentator Keith Augustine has criticized the survivalist interpretation of NDE's. He has also exposed "weaknesses in the research methodology, paucity of the data, and gaps in the arguments". His criticism has been answered by Greyson, who suggests that the materialist model favored by Augustine is supported by even less data than the "mind-brain separation model" favored by many researchers within the field of near-death studies. The findings of NDE-research has been contested by several writers in the fields of psychology and neuroscience. Susan Blackmore has contested the findings of NDE-research, and has instead argued in favour of a neurological explanation. Psychologist Christopher French has reviewed several of the theories that have originated from the field of near-death studies. This includes theories that present a challenge to modern neuroscience by suggesting a new understanding of the mind-brain relationship in the direction of transcendental, or paranormal, elements. In reply to this French considers the conventional scientific understanding, and introduces several non-paranormal factors, as well as psychological theory, that might explain those near-death experiences that defy conventional scientific explanations. However, he does not rule out a future revision of modern neuroscience, awaiting new and improved research procedures. Jason Braithwaite, a Senior Lecturer in Cognitive Neuroscience in the Behavioural Brain Sciences Centre, University of Birmingham, issued an in-depth analysis and critique of the survivalist's neuroscience of some NDE researchers, concluding, "it is difficult to see what one could learn from the paranormal survivalist position which sets out assuming the truth of that which it seeks to establish, makes additional and unnecessary assumptions, misrepresents the current state of knowledge from mainstream science, and appears less than comprehensive in its analysis of the available facts." Martens noted the "lack of uniform nomenclature", and "the failure to control the studied population with an elimination of interfering factors", as examples of criticism directed towards near-death research. Engmann points out that NDE research does not fulfil quality criteria of medical studies, namely objectivity. But criticism of the field has also come from commentators within its own ranks. In an open letter to the NDE-community Ring has pointed to the "issue of possible religious bias in near-death studies". According to Ring the field of near-death studies, as well as the larger NDE-movement, has attracted a variety of religious and spiritual affiliations, from a number of traditions, which makes ideological