Perception of reality constantly intrudes upon my thoughts, especially while high.

The most intriguing part, is when you are able to cross over and catch a glimpse of what another person might see. Now, next time you're doing this, try this: when you can see both things, two different perceptions of the same subject, Pick the NEW one. What you're doing is rewriting a beleif, a little batch of data that you got in your head a long time ago, and applying a different perspective to it. This action of picking a new beleif, will change you entirely. Not in the completely dramatic sense, but if you take the time to watch yourself think, you'll start noticing that the new perception you chose will always pop up.

Do this: watch fight club three times. Twice sober, and then again stoned.
The first time, you'll watch it and it might interest you, it confuse you, but the ending will be a glorious one.
The second, with the truth behind every situation obvious, you'll understand most of it.
But the THIRD time...

The third time is magical. You can see every connotation to reality and the mental "illness" of tyler durden, you'll understand the relationships and insanity provoked by the story line behind the story line. And the entire film changes.

Let your mind evolve.