Figure2: The progression toward excessive drug use

The progression toward excessive drug use: On the x-axis is the distribution of choices. One option is drug consumption, the other option is the set of conventional activities. On the y- axis in the left column of panels is the subjective value of each option. In the second and third panels, the value of conventional activities has decreased. This represents the adverse effects of drug use on other activities. The right panel of columns shows the combined value of each choice distribution. This is the variable that controls choice according to economic theory. See text for discussion of other aspects of this graph.