im pretty sure this is the dutch study your refering to (but i could be wrong), this artical appears to contradict much of it, it was from one off the links i used from above, http://skepdic.com/nde.html

heres most of it-
A 13-year Dutch study led by Pim van Lommel and published in Lancet found that 12 percent (or 18 percent, depending on how NDE is defined) of 344 resuscitated patients who had experienced cessation of their heart and/or breathing function reported an NDE. If the cause of the NDE were purely physiological, the researchers reasoned that all of the patients should have had one because of their similar plight. Psychological factors were also ruled out by the researchers, as were the medications taken by the patients. However, the researchers believe that

neurophysiological processes must play some part in NDE. Similar experiences can be induced through electrical stimulation of the temporal lobe (and hence of the hippocampus) during neurosurgery for epilepsy, with high carbon dioxide levels (hypercarbia), and in decreased cerebral perfusion resulting in local cerebral hypoxia as in rapid acceleration during training of fighter pilots, or as in hyperventilation followed by valsalva manoeuvre. Ketamine-induced experiences resulting from blockage of the NMDA receptor, and the role of endorphin, serotonin, and enkephalin have also been mentioned, as have near-death-like experiences after the use of LSD, psilocarpine, and mescaline. These induced experiences can consist of unconsciousness, out-of-body experiences, and perception of light or flashes of recollection from the past. These recollections, however, consist of fragmented and random memories unlike the panoramic life-review that can occur in NDE. Further, transformational processes with changing life-insight and disappearance of fear of death are rarely reported after induced experiences.

Thus, induced experiences are not identical to NDE...*

However, the Dutch researchers seem to be assuming that no significant life-insight changes occur in people who have had induced NDE-like experiences. They cite no evidence that this is so. Also, we can't assume that only those who report NDEs had an NDE. Nor can we be sure, of course, that those who report having had an NDE actually had one. Two of the participants first reported having an NDE two years after their close call with death. It is possible they constructed a false memory. It is possible that others had an NDE but don't remember it due to either different abilities in short term memory or to the timing of their experience vis-Ã*-vis when they regain consciousness. The only significant factor between the NDEers and non-NDEers in the Dutch study, according to van Lommel and his colleagues was age: those who had NDEs tended to be younger. This is partly due to the fact that older cardiac arrest patients are more likely to die than younger ones, but it may also be partly due the fact that younger brains are more likely to have better short term memory functions than older brains.

The Dutch researchers found other significant differences between those who reported the NDE and those who didn't, but they occurred after the experience. "NDErs had become much more empathic and accepting of others since their NDE than had the non-NDErs. And NDErs had become both more appreciative of the ordinary things of life and much less afraid of death than had the non-NDErs."* They also raise the possibility that consciousness may exist outside of the brain.

Raymond Moody is sure that NDEs are evidence of consciousness existing separately from the brain. He thinks that NDEs prove the existence of life after death. Skeptics, on the other hand, believe that NDEs can be explained by neurochemistry and are the result of brain states that occur due to a dying, demented, or drugged brain. For example, neural noise and retino-cortical mapping explain the common experience of passage down a tunnel from darkness into a bright light. According to Susan Blackmore, vision researcher Dr. Tomasz S. Troscianko of the University of Bristol speculated:

If you started with very little neural noise and it gradually increased, the effect would be of a light at the centre getting larger and larger and hence closer and closer....the tunnel would appear to move as the noise levels increased and the central light got larger and larger....If the whole cortex became so noisy that all the cells were firing fast, the whole area would appear light (Blackmore 1993, 85).

Blackmore attributes the feelings of extreme peacefulness of the NDE to the release of endorphins in response to the extreme stress of the situation. The buzzing or ringing sound is attributed to cerebral anoxia and consequent effects upon the connections between brain cells (op. cit. 64).

Dr. Karl Jansen has reproduced NDEs with ketamine, a short-acting, hallucinogenic, dissociative anaesthetic.

The anaesthesia is the result of the patient being so 'dissociated' and 'removed from their body' that it is possible to carry out surgical procedures. This is wholly different from the 'unconsciousness' produced by conventional anesthetics, although ketamine is also an excellent analgesic (pain killer) by a different route (i.e. not due to dissociation). Ketamine is related to phencyclidine (PCP). Both drugs are arylcyclohexylamines - they are not opioids and are not related to LSD. In contrast to PCP, ketamine is relatively safe, is much shorter acting, is an uncontrolled drug in most countries, and remains in use as an anaesthetic for children in industrialised countries and all ages in the third world as it is cheap and easy to use. Anaesthetists prevent patients from having NDE's ('emergence phenomena') by the co-administration of sedatives which produce 'true' unconsciousness rather than dissociation.*

According to Dr. Jansen, ketamine can reproduce all the main features of the NDE, including travel through a dark tunnel into the light, the feeling that one is dead, communing with God, hallucinations, out-of-body experiences, strange noises, etc. This does not prove that there is no life after death, but it does prove that an NDE is not proof of an afterlife.

While neural activity might explain bright lights, buzzing noises, and hallucinations, there are some aspects of some NDEs that still remain puzzling. Some people who are thought to be dead, but are actually just unconscious, recover and remember things like looking down and seeing their own bodies being worked on by doctors and nurses. They recall conversations being held while they were "dead." Of course, they weren't dead at all, but they feel as if their mind or soul had left their body and was observing it from above. Those who have had such experiences--and they are many--often find them life-altering and defining moments. They are convinced such experiences are proof of life after death by a disembodied consciousness. But are they? It is possible that a person may appear dead to our senses or our scientific equipment but still be perceiving. The visual and auditory perceptions occurring while unconscious-but-perceiving may be produced by a variety of neuronal mechanisms. It is possible that the soul leaves the body, but it is not necessary to posit a soul to explain these experiences. In any case,

we do not yet know whether NDEs take place just before the crisis, during it, just after it or even during the process of trying to describe it to someone else. If clear consciousness were really possible with a completely flat EEG, this would indeed change our view of the mind/brain relationship, but so far this has not been conclusively demonstrated (Blackmore 2004: 364).

Finally, Raymond Quigg Lawrence (Blinded by the Light) thinks that NDEs are the work of Satan. Perhaps. Or, they may be telepathic communications from doctors, nurses, or others in attendance when the subject is near death. Or, they may be mixed memories composed after waking up and hearing others talk about what was happening while one was near death. Or, they may be recollections of subconsciously recorded data overheard while in a groggy state. At this point in our knowledge, to claim that NDEs provide proof that the soul exists independently of the body seems premature.