1.   The pair announced that they had identified a genetic defect in the dopamine system of some alcoholics.

2.   And so he built a virtual bee inside a computer, with a model of the dopamine system that might explain genuine bee behavior.

3.   Bigelow said there was a potential problem with drugs that target the dopamine system.

4.   According to the study published in Science, cannabinoids, through a complex chain of events, rev up the dopamine system.

5.   But compulsive gamblers seem to have vulnerable dopamine systems, he said.

6.   Compulsive gamblers seem to have vulnerable dopamine systems.

7.   Hence, the dopamine system has long been proposed as an actor in impulsive, extravagant behavior.

8.   Recent experiments on bees, monkeys and humans provide the basis of these ideas about the dopamine system, which are by no means proved.

9.   Scientists believe that this midbrain dopamine system is constantly making predictions about what to expect in terms of rewards.

10.   Some people seem to be born with vulnerable dopamine systems that get hijacked by social rewards.