Yep. Definitely Dopamine. Amphentamine, opiates, weed, anything with its main function through dopamine. Hallucinate a lot on them all, even if I've been up for only 20 hours and am on 15 mg of dextroamphetamine. Things will twist and distort, I find patterns in everything I look out, the most bland rock becomes covered with identifiable pictures I have already seen before at one point in my life (it may change into others if I look at it too long). Hearing my mother (I don't live with her) call my voice from up the stairs in a phantom voice, or hearing her whisper my name, and realizing it is just the faucet. I am always thought as an extremely off individual by all who I meet, though ussually interesting. I have trouble speaking, sometimes becoming incoherent, putting verbs or ajectives in the wrong place while speaking. People have had a hard time understanding me recently. Sounds like a definite underlying problem instead of the drugs.
Other times when I speak I won't seem to get to the point, and my reasoning is unusual (though it is a reasoning that allows me to see into the real motives of people, and I almost always end up close to the truth).