I think it operates more on the attention mechanism, as well as exploring different (and often unbeknownst) search space in the processing (the long-term effect

I think it operates more on the attention mechanism, as well as exploring different (and often unbeknownst) search space in the processing (the long-term effect of which can be biological in ways we don't understand). And if taken regularly and had a certain training for a prolong peroid of time, they should be able to "increase the quality" of perception the same way when you play tennis regularly and with enough time you will develop the motor skills and can finally "feel" and effortlessly hit the ball at the center of the racket while swinging your hand in a way the racket travels straight. Or the same way one becomes less tone-deaf or more sensitive to sounds, etc, (of course, it may go the other direction too - but I think the computational cost is quite different (acquiring vs losing) - still, it's definitely possible, eg, for one to 'unlearn' their mother tongue, etc).