" The results of decades of neurotransmitter-depletion studies point to one inescapable conclusion: low levels or serotonin, norepinephrine or dopamine do not cause depression. here is how the authors of the most complete meta-analysis of serotonin-depletion studies summarized the data: " Although previously the monoamine systems were considered to be responsible for the development of major depressive disorder (MDD), the available evidence to date does not support a direct causal relationship with MDD. There is no simple direct correlation of serotonin or norepinephrine levels in the brain and mood.' In other words, after a half-century of research, the chemical-imbalance hypothesis as promulgated by the drug companies that manufacture SSRIs and other antidepressants is not only with clear and consistent support, but has been disproved by experimental evidence. "