The Science of Addiction

2. A sudden strong and unreflective urge or desire to act.
3. Lasting for a very short period; temporary.
8. Of, relating to, or involving conscious intellectual activity, such as thinking, reasoning, or remembering.
9. Extremely delicate and light in a way that seems not to be of this world.
11. Relating to the chemical processes and substances that occur within living organisms.
12. The process of change by which an organism or species becomes better suited to its environment.
14. Chemical substances that transmit nerve impulses across a synapse to a target cell.
15. Relating to a person's body, especially as opposed to their spirit; material or tangible.

1. A ghost; something widely feared as a possible unpleasant or dangerous occurrence.
4. The capacity to recover quickly from difficulties; toughness.
5. The act of setting someone free from imprisonment, slavery, or oppression; release.
6. The tendency of the body to seek and maintain a condition of balance or equilibrium within its internal environment.
7. Having many curves and turns; lithe and supple.
10. Catch in or as in a trap; trap.
13. A division or contrast between two things that are represented as being opposed or entirely different.