Take crack cocaine. Particularly in the early days of the policy, ninety percent of the people being arrested were black, even though they didn't use the drug at higher rates and even though their numbers in the general population are so low. How could that be? The thing is, you place all your resources in communities of color. And if you do that, you're going to arrest black people.

If you're a member of a despised group, look out! They'll find a drug and associate you with its use. There are a lot of people in the gay community using methamphetamine and paying taxes and going to work and doing well.

High Price: A Neuroscientist's Journey of Self-Discovery That Challenges Everything You Know About Drugs and Society.

Our ability to study the brain has been limited because of our tools and our tools have only allowed us to look at one neurotransmitter and we haven't looked so much into co-localization and co-release of transmitters. Our thinking is hampered by our tools.

You have rappers saying "stay off drugs, go to school" - empty verbal behavior. I think all of this became institutionalized in the early '90s. And it's become more and more solidified, more and more entrenched.

Crack in the early 1980s or mid 1980s I'm sorry is that one of the worst myth is that one hit and you're addicted for life. We saw that in 1980s and we're seeing it again with methamphetamine today, one hit and you're addicted and it simply not true, addiction requires work not the people should go out and experiment or do these themselves but the fact is that's a myth and the concern is that, it's dangerous because when people perpetuates that myths and then when young people are people actually try methamphetamine or crack cocaine and find that, that doesn't happen to them.

Dopamine makes up less than one percent of the brain's neurotransmitters. It's a small portion. Dopamine is released when people are happy, angry, stressed. So it's really hard to call this specific neurotransmitter "the pleasure neurotransmitter."