He's either a crackpot or just shamelessly cashing in on people's insecurities. Either explanation is a vastly more likely prospect, I think, than there actually being an afterlife. At least this book is a little less insulting than that one where a child tries to convince us of the afterlife. I think it's called, Heaven is for real. At least a scientist begins with a little more ethos than a child.
Anyway, as for your question, I can't even imagine such a scenario. One of my greatest fears is failure, and if I had nothing to fear, then I could never fail. It doesn't make any sense. The only things worth doing are those which pose some threat of failure. By the way, I'm already utterly loved and cherished by a multitude of people, i.e. my family, and it's a fact of which I rarely take any notice. Love doesn't really affect my plans.
Sounds like, as does every other normally logical thinker made a whole shit ton of assumptions of a "supernatural" area he briefly experienced that we don't know anything about. I hope he has solid evidence of his claims.
I once had a dream that I was falling, I did not wake up on the ground, was my mind deceiving me? I do not know but I did not maintain a belief as though I had fallen. Did it actually happen in another plain I don't know. Form photography and may own experience I have learned the mind fills in information that my eye does not detect My mind is actually creating a fictitious reality. Most people do not see things or remember things exactly the same for this reason, until it is pointed out to them and there are enough processed similarities they come to a general consensus. The mind even allows for the changing of one belief for a more palatable one. I am not denying Dr. Alexander's belief in what he believes "happened" to him; there is also the possibility, with so many near death experiences in our midst, his mind filled in what it could not process in an attempt to complete the picture. It is a survival tool that inform the mind how to best respond to a perceived threat or desire. God and Heaven is an amazing thing, I just don't believe this man has any plausible information to share any more than a person who experiences alien abduction. Get a group of people, all die together, come back together, repeat several times, compare notes, and he may have a theory.