The exact same thing happens with self transcendence or ego death, which Sam has also spoken about. By losing the sense of being an agent in the body trapped in the head and in the conscious thoughts of "me" as an image, you become more aware and in tune that you are, at the minimum, the whole body at work. You're more like a wave that flows instead of specific water molecules in it, if that makes sense. Instead of fixing yourself as the impressions, the contents that appear within awareness, you then flip and identify more with the aware space in which they appear in. This is profound and quite a change from the way we typically think, especially for us Westerners, who still adhere to social views of a Christian ego. This view of awareness being prior to contents appearing in it also correlates to arguments Harris and Pinker both allude to with the brain, but I know personally that Sam has spoken a better deal about that in Waking Up and on his podcast. Sam argues, and I would agree with, that happiness and peace can exist prior to external influences, conditions, and stimuli in this state of realization. Consider for just one moment how odd that seems to the way we normally look at the world and happiness as something to be acquired through time, effort, and a future. This is what gurus mean when they about "now" being pure bliss and peace, regardless of any wooly claims they make at higher concepts about the universe about Ishvara or deities; they're talking about a state of 'not-self', of ego death.
The problem however, like free will, is that accepting that state of self as fleeting and illusory seems like the most destructive thing you can ever do. There have been users on this very forum that I have conversed on the subject with, and they were so attached to such beliefs that they would try and argue suicide if their conceptions and notions of selfhood and control were bogus. "If I'm not me and what I think I am, why should I live?" and familiar retorts like that. This alludes to what I said earlier, where belief drives behavior: if you think of yourself as only the impressions in your awareness, cut off from everything else, you're a receding flame that you try to continue to fuel. No way in hell are you escaping that well, or in peace, so long as you hang onto those concepts. Your lens from the very beginning is incompatible what "what is" of reality, so it'd be better to see through it instead of trying to see the world from it.
"I'd love to take a walk in the beautiful woods. I'd like to surround myself with peace and serenity and inquire into my true nature." (Putting on hiking boots, opening the camper door and stepping out), "Here I go." 
