The neurons of the mesolimbic dopamine system originate in the midbrain and extend axons towards the limbic system of the forebrain. The mesolimbic dopamine system is associated with the reward pathways and is implicated in addiction and psychiatric illness.
Many of the drugs of abuse produce psychomotor effects, which make the user to feel more in control and energetic, which is linked to the reward pathways and thus, the mesolimbic system.
Thus, the blank can be filled with psychomotor activation, mesolimbic dopamine system.