1.   Brain scans found that GVG reduced their dopamine levels.

2.   By controlling dopamine levels, GVG blocks the high that a drug produces.

3.   Dopamine levels doubled in animals given the drug compared with animals injected with an inactive form of marijuana, DiChiara said.

4.   Five of the fifteen addicts have not relapsed and are being re-examined with brain imaging to see if their dopamine levels rebound.

5.   Increased dopamine levels are involved in heroin and cocaine addiction, and researchers now believe in nicotine addiction.

6.   So can buproprion, an antidepressant drug that increases dopamine levels.

7.   The finding is of interest because dopamine levels are sharply increased by addictive drugs like cocaine.

8.   The low dopamine levels lead to an imbalance, allowing excitatory neurons in the pallidus to cause problems such as tremors, rigidity and slowed movement, Brodner said.

9.   When dopamine levels are high, as in childhood, the nervous system is extremely active and the interval clock runs faster.

10.   Ross and colleagues speculated that caffeine might increase dopamine levels.