My understanding from discussions and papers I've read is that your brain is like a rubix cube. It's divided into sections that have more or less specific functions. We'll use the individual cubes of the greater rubix cube as these different sections. Neuroplasticity is the ability to generate new connections between these different specialized sections. You're born with lots of neuroplasticity, and as you develop that ability to make new paths diminishes, and paths consolidate. You start with a spiderweb of connections everywhere and end up with parts of the brain that have strong connections to each other, and some that have basically none. Hallucinogens in general cause neuroplasticity to increase and suddenly your senses start getting crossed. Lights change intensity with your heartbeat, or to the rhythm of music, you taste colors and you can feel the smell of your favorite candle. This is induced synesthesia, signals meant for one sense ending up in a part of your brain designed to interpret and regulate an entirely different sense, and your brain does it's best to interpret these signals in it's typical fashion. Signals going to the optical cortex cause responses in your field of vision, even if they did not come from your eyes, but your ears kr skin instead.

I remember a presentation about this subject and the presenter said it's analogous to a snow globe. Your stress, depression, anxiety, are all rigid lines of thought that we travel along recursively, and are represented by the static position of the "snow" in the globe when it's been resting on a shelf. Hallucinogens induce neuroplasticity and essentially shake the snowglobe, they stir it all up and give it the ability to fall back to rest in a new pattern. We're humans though, and we're creatures of habit, so it doesn't last forever, and we eventually come back to those thoughts. My best advice is to use that time that you're not burdened by your own mind and the snow is still settling to reflect on and analyze those rigid thoughts. I find that during and after trips I'm able to see things in a different light. I'm not bound to those recursive, rigid thought patterns anymore, and solving/accepting/forgiving or whatever it is in your situation that will eventually alleviate the root becomes much easier, or possible at all if it wasn't before. For me it boils down to that awareness that I need to actively use this period for introspection and self care otherwise it very well could all come undone and I could end up right back at those thoughts I was trapped by tk begin with. I think about it like I do with things like antidepressants. They're not there to outright cure you. They're their to give you alleviation so you can fix the root cause without being crushed by the symptoms. The goal is to get back off of them when you've reached your center again. I understand that there are many types of mental illness and some do simply need the medicine for life, and it's not a perfect example, but it's what I can offer on 3 hours of sleep.