The classic world emerges from quantum world through quantum decoherence. A classic object, eg a billiard ball, when not observed, cannot seem to be all over the place all at once even if in isolation, its constituent particals can. This is because in interaction, the waves (of probabilities of finding the particals), cancels everywhere exept at the place where the billiard ball is found. What then does it take for quantum effects to manifest in the brain?
It is important to understand that decoherence (hence wave cancelation) is not a law of nature. It is a boundary condition of nature. Coherence in macroscopic world is just thought unlikely because particles, thought to be unguided by some mind don't know how to move in synch. In otherwords quantum mind (which may constitute the wavefunction) is not considered right at the start, and not excluded via calculation, contrary to how the mainstream scientist would like you to beleive. Then they are shocked when the find quantum effect in photosynthesis etc