Hey Rondele,
if we would start from the point that we, let's say, as part of our "higher self" were sent here to "learn". The consciousness might not be directly planted in the brain, but if the spirit is fed by consciousness, he would also get the negative impression.
Brain function or personality can surely suffer from accidents (loosing the ability to remember what was before the accident, some suffer from the result that the accident brought with them, not being able to use the whole body, maybe having lost parts of it.
But whem talking about soldiers, that got hostile after coming back from war, never forget that what they experienced can also cause a total change in personality. All the senseless violence and killing happening there, blood, guts, dead comrades, simply ruins the psyche.
So it is not the damage to his brain alone, but also what he experienced.
But not to water down what brain damage can cause to the body, our personality is also part of the brain, you have surely heard about patients having removed parts of the brain damaged by cancer, e.g. losing the ability to speak, because there is a part of the brain, that is responsible for the ability to speak.
I never heard about a part of the brain, where our personality is centered, but as all of our actions are controlled by the brain, the personality must also be a part of it, maybe spread over the whole brain.
If it is like this, then the posibility, that the injury swapped his personality, is given.
When asking what is a life review good for having lived a life with such a tremendous negative change, life review can only be considered, if looking on the beliefs of this soldier.
He was a soldier, that is no contradiction to be caring and loving when it comes to family and friends, but what about the point of view, or with which kind of belief he chose to be soldier, could be that he had a strong hate against any people down there (it is crooked after all, when one goes to war, he is obviously not interested in making friends at first sight), so from the point, that he should have lived in peace and harmony so that might be the lesson learned, thou shall not kill
(it is surely a good value, but how can we live according to such values, reality teaches that people do not give a damn about this, it is easier to do not so...but that is no real excuse, but this does not really belong here, since it is not opened to talk about moral issues).
It makes sense to how spiritual teachings encourage us to live. (I tried only to find some explanations, I new to this kind of thinking and not a
very spiritual person ..
)
But it does not mean, that he lived a senseless life, I think also this kind of lessons are also a possiblity to grow (no I am not a sadist), morbid and cruel, but if they were meaningless, they would not be here. I do not claim them to be destiny, but war is mostly like a result of historical failures (made on political ground).
Mhh, but after all, stone age has passed, but man only changed from bat to machine-gun.
regards,
pulsar