One problem with the chart - where do mood stabilizers like Lithium and Depakote fit into this chart?  I ask because psychoactive substances should be a superset of psychiatric medications, which has 4 major drug classes (stimulants, depressants, anti-psychotics and mood stabilizers).  So shouldn't this chart have 5 circles?  I know it won't make the chart any simpler, but I'd like to see this article and the Psychiatric Meds and Psychopharmacology articles work more closely together.