Which administration of a drug gets to your brain the fastest? The slowest?

Methods of drug administration in order of fastest to slowest CNS response. Intravenous (IV) drug use in which the drug is injected directly into a vein and enters the bloodstream to reach the brain. This is the quickest way of achieving a psycho-active drug effect.

hope this helps

interact. i am not 100% sure with this, but you can communicate without speaking, so i think interacting is more precise answer.