Fenwick is supposed to be neuropsychiatrist based in London and Parnia is, I think, a medic.
Fenwick has made a name in NDE research. His work is, in my opinion, fundamentally flawed, logically implausible and heavily biased to the survivalist interpretation. All his 'evidence' boils down to anecdotal reports.
His scientfiic arguments against the 'dying brain' hypothesis of NDE all represent severe misunderstandings of the arguments, as they were made, factual errors, logical errors, and odd claims about the brain that i cannot find sharred by any top neuroscientist.
So - basically his arguments are very poor indeed.
I have less knowledge of Parnia, but some of his arguments on the programme were pure woowoo. A paraphrased example...
"just because a brain area is active during emotion, does not mean that the emotion is based on that brain activity. Its the same for ghosts, just because neural activity may increase during the experience (consistent with hallucination ideas) this does not mean that activity is 'producing' the experience"
Now - in part, some aspects of this argument are interesting, or could be made more interesting if expressed properly - but it is his use of them, and how he expressed them that makes them flawed.
It violates Occam (makes unecessary assumptions), assumes to be true (dualism) that which it seeks to establish as true, and tries to use the 'it does not prove it' as a shoe-horn for forcing in a woowoo idea. I am sure others here, far more qualified than me, can pick out many other flaws in this approach.
In addition - he claimed that mental experience has been shown to occur when the brain is electrically inactive. This is blatantly false. The cases I know of do not show this at all - and he should know better.
To answer the OP - Fenwick's arguments are very poor indeed and he has little consequence in the field of neuroscience of strange experience
