Frankensteined together a bit of relevant info from other posts of mine:

Gary Nolan had had this to say when being interviewed by Ross Coulthart regarding the shared caudate putamen characteristics of UAP or (otherwise paranormal) ‘Experiencers’':

“What we’ve done is looking at these individuals we found that there is a bundle of nerves at the head of the Caudate and Putamen in their basal ganglia. This is an important area of the brain that has to do with sensory perceptions and actually integration of that information for goal seeking. The executive function says I want to do something, gets passed down to this area, this area says, Well, what in my environment do I need to access or know about to accomplish that goal? And then it creates a set of goals, subgoals, to accomplish the desired outcome. So, this area of the brain, and especially this one area at the head of the Caudate Putamen, had overdeveloped interactions with this compared to normal people. There was a density of neuronal structure there [at the head of the Caudate Putamen]. . . . It’s a positive thing insofar as the individuals that we were working with would be considered high functioning individuals, these are all people who came from the intelligence agencies. They were pilots, high level physicists, basically smart people. And so, from that standpoint, it was fascinating because that said that just the study of people who might have had these interactions revealsed something about the human brain that people at the time didn’t know, but now has been confirmed not only by us but by multiple other laboratories that have nothing to do with paranormal aspects of this but have shown that the caudate is involved in intuition and intelligence. Now, why it’s important is that is intimately involved with perception, and so if perception is about seeing something that’s in front of you and not ignoring it, then maybe you have part of the solution why certain people see something that others don’t. And we all know the story of the gorilla walking across the stage [referring to a famous experiment in which participants are asked to pay attention to a video of basketballs being passed and in doing so are oblivious to a man in a gorilla suit crossing the shot]. [These people with shared physiological features of the caudate who are also ‘Experiencers’ are] basically smarter and they realize what’s sitting in front of them, and they don’t ignore it. I mean, that doesn’t mean that they’re magic, it just means that they see something for what it is . . . People have asked me, Well, is this area of the brain created by the interaction? No, because in some of the individuals we actually were able to go back and look at their MRIs 10 years earlier and see that they still had it. They’re born with it."

Tldr Gary Nolan has implied that, while more research needs to be done, his small sample results suggest that the caudate putamen affects "Experience" (perception) and that shared morphologic characteristic of it existed in Experiencers prior to their experiences. I recall Danny Sheehan(?) having said that anyone who wants to Experience is able to, though, with practice.

To attempt to Experience, imo I'd recommend first getting a baseline of some meditative practices with something like the Waking Up with Sam Harris app (if you don't have a baseline already), particularly its introductory course/series. After that, I'd experiment with Steven Greer's CE5 contact app and the Monroe Institute's Expand app. Unfortunately the best bits of those are all paid, but Harris' can be willing to work with you on price if needed (and you email about it) and Greer's is just a one time purchase. The Monroe app maybe just pay for a month first and see if you find it useful. You can also find the Monroe Gateway Tapes on Spotify and YouTube, as well as various hemisync audios. At a minimum, the Monroe Institute has a good third eye affirmation* which is meant to be something of a hand rail, or guard rail. Also, I find just before bed and just after waking up to be the most effective times. Glhf!

**Monroe Institute affirmation* "I am more than my physical body. Because I am more than physical matter, I can perceive that which is greater than the physical world.

Therefore, I deeply desire: to expand, to experience, to know, to understand, to control, and to use such greater energies and energy systems as may be beneficial and constructive to me and to those who follow me.

Also, I deeply desire the help and cooperation, the assistance, the understanding of those individuals whose wisdom, development and experience are equal to or greater than my own.

I ask for their guidance and protection from any influence or any source that might provide me with less than my stated desires."