[catskul2]

Have you considered explicitly using weed or shrooms as an on-ramp to exercising this ability? You could devote some time and slowly build up your ability.

Just as you can learn to wiggle your toes independently, or play the piano, or learn a new language, which require wiring new pathways, it's possible to learn to wire new pathways to non-motor areas of your brain. But it likely requires the same amount of effort.

I believe that developing the ability to mentally visualize more vividly is the explicit goal of some certain kinds of meditation. If you're interested you might look into "fire kasina".