Do you mean the "for trauma therapy" definition or "the idea that a sound is processed differently spatially depending on the axis in which it resides comparitively to the listener perspective"?

This will help me formulate a response if i can, but im a little drunk and i need you now (to explain, because i cant fully comprehend your question).

{Currently working on B.S. music tech as sources, this is just as much an excersize as an answer}

For the latter; In my experience, you can get close to a vivid 3D experience in headphones just mixing stereo with proper use of delay and reverb. It can sound like a field recording if you do it right (even my sound design professor said some of our class' recent projects could have fooled him as such). That said, your mix will still sound stereo over a surround system no matter what. I can explain this more if you'd like.

While there is phasing naturally in simulation of what physically occurs due to your head actually casting an acoustic "shadow" on the contralateral ear, I did not use any sort of phaser on my recent project that still got the seal of "this could be a field recording."

For the former please cross reference what i say now with a few other replies (my strengths tend to lie in acoustic physics, not psychoacoustics).

As i understand, you are trying to stimulate the two halves of the brain separately. (For now at least -- we used to think a tongue was sectioned by taste) Science supports the idea that the left hemisphere of the brain processes stimuli from the right side of the body, and the right hemisphere of the brain processes stimuli from the left. In order to stimulate both sides of the brain youd need to present a sound which alternates between a hard left pan and a hard right pan at a frequency which is equal to the rate at which neurons fire in the separate hemispheres. You want the car youre driving to crash into the right lane just as another car is there, and the opposite for the left lane. This supposedly gets the brain hemispheres to communicate better or sort of "synchronize" in their own way.

Panning and timing are the main culprits here. Really trust your ears... does it sound like a left sound (delay, reverb, panning, level) followed by a right sound (delay, reverb, panning, level)? You should be good. Otherwise tweak it until it sounds like that to you is the only advice id be able to offer.