Some of the changes I've experienced seem to be accessible to those with natural reflective abilities. In this comment Oshaberi writes:

I have no memory of a time when I didn't think self-reflexively, I'm pretty sure I was doing it as far back as kindergarden. Though I'm not sure I took it to the extremes of some of you, I only ever did modest personality modification :). I realized I could like any previously hated food just by trying. It's somewhat useful having such great control over thoughts and emotions.

(Also see my comment here)