Part 2 of 2
You need to integrate this "island of cognitive memory/function" with your "normal" state of consciousness. Here's one idea... you can write down things in your "normal mood/consciousness" so that you can keep on hand to read in this "new mood", in order to remind you of things that important. And visa versa, from the "new mood" person to the "normal mood" person. Like a dialog. I can give some suggestions for you to get the idea:
What does this do? It creates little neural pathways from the normal to the new, from the new to the normal. In fact, anything you can do that is a commonality between the two will help you integrate.
I've been feeling more and more fear that what I experience on a daily basis is simply me reflecting upon my death.... I'm having a growing sense of dread that either what I experienced on LSD was true, about the doing bad things & dying, or that this world is all an illusion of some kind...
First of all, "Welcome to a new paradigm about life." Ok so you now have a few new ways of thinking about what life is. Maybe you did some really bad things, you died, and now you're in some kind of remembering your life or after-life or purgatory. Well well, what's one to do in purgatory, hmmm? Maybe see a psychologist? Take some pills? Sounds rather ordinary, even banal. Or how about making some changes in your life like learning how to dance or taking a class in improv? It's up to you how you want to deal with "the possibility that you're dead".
Now there's nothing actually inherently wrong or depressing with the belief system that you're dead and remembering your life, other than the discomfort or fear you have about it. In fact, I'll bet you some people believe exactly the same thing and feel wonderful about it.
Think about what people "believed to be true" 100,000 years ago. It would be crazy by today's modern standards. But it didn't "disturb" them. One sacrificed to the sun god or whatever, and that's just the way it was. More modern but still ancient Egyptian kings just knew that they would be immortal by building pyramids and had slaves build their empires. We consider such beliefs and customs to be wrong/crazy/evil today. Our sense of self and civilization and such has evolved (at least for some people).
So we grow up now in modern life, learn a bunch of things about how the world works, and "believe" in all this modern stuff. You've watched thousands of tv shows, movies, books, and all these fictions have deep roots in philosophy. You've been watching/absorbing life from a certain point of view, and you take a drug and wham, your world gets knocked for a loop.
Now what if we learn some time in the future that all our dreams are "actually real". And they are all recorded and "future people" get to look back on us and think how horrible we all are in this day and age. Oh shit. I've done horrible things in my dreams. Maybe I'm really a terrible person because of it. If dreams are real, well you can at least take comfort that most everyone is going to be looking pretty damn guilty of one thing or another along with you.
But what is a guilty person to do? Cry about it the rest of their life? Or make some positive changes? The real issue is not what has happened, not that you've done some terrible things or thought some terrible thoughts, but what do you want to do about it now? Who do you want to be?
My mind keeps connecting dots that shouldn't be connected, like the fact that movies like "Vanilla Sky" and "I Heart Huckabees" exist to show me that this world doesn't matter.
You may or may not remember when you first started doing this, but this is a little "trick" that you probably learned, or relearned, while on LSD.
When we are babies, the only thing we can do is connect dots between this and that, and it's all a blur at first. You're in a high chair. A doorbell rings. Dog barks. Mama says "here's some food" => [Doorbell, dog bark, mama speaks]. You think, "Is this how things works?" Some time later, [Doorbell, dog bark]. Now as a baby you said, "Waaiit a minute! Mama didn't speak! What the heck is going on here?" Then [Doorbell, dog bark, something else]. Then eventually, as a baby, you said to yourself, "Ahhh I get it now! Doggy barks to doorbell!"
Ok, so maybe you weren't such an intellectual baby. But making irrational or non-rational dot-connecting is how we learn when we are very young. As we grow older, we learn to replace this more and more by logical dot-connecting. But non-logical dot-connecting is still used when we learn new things, especially complex things like new physical skills, emotional skills, and social skills. In a nutshell, it's just "association".
So LSD, other mind altering drugs, and "spiritual experiences" throws us into bypassing this logical brain function and goes back to non-logical dot-connecting. There's nothing inherently good or bad about this. Have you ever met someone that is kind of batty, very colorful, creative, possibly bi-polar, and yet somehow still manages to make their way through life? Maybe they're also very "spiritual". They're living more in the non-logical dot-connecting way of seeing life. Your current fear and dread is someone else's standard way of navigating through life.
The "problem" is not necessarily that you're connecting weird dots. It's just that you're just a little stuck on the fear of the whole thing, and having a negative attitude about it. Try this:
In a matter of minutes, you'll find that you can do this and it's uplifting. You're NOT stuck/doomed to making all these negative associations! Yay! The fundamental cognitive "skill" at work here is neither good nor bad, it's just "a skill at making instant non-rational connections". How you use it makes all the difference. Like, for example, mixing chocolate and peanut butter? That's not logical! "You got chocolate on my peanut butter! You got peanut butter on my chocolate! You can use that skill for fun and games, not just bleak outcomes (you drama king, you).
And that brings us full circle back to the reason you took LSD in the first place. Assuming you were looking for some type of "new thing to do", you might consider that you still have that need and desire for something new and interesting in your life. So in addition-to or alternative-to your little druggie adventures, consider doing some other things you've never done before. Like cooking. Or ballroom dancing. Hey, what's the worst that could happen? You're already dead, so you don't have to worry about that anymore. :)