Table 2.

Appearance of DSM-IV criteria in animal studies of drug addiction

DSM-IV criterion	Behavioral equivalent
1. and 2. Tolerance, withdrawal	Tolerance, escalation of drug use
3. Using more than intended	Impaired control, neurocognitive deficits
4. Difficulty restricting	Resistance to extinction
5. Great deal of time spent	Increased motivation for drug
6. Other activities given up	Drug preference over nondrug rewards
7. Continued use despite problems	Resistance to punishment