How hormones like estradiol, progesterone, and testosterone regulate mood and cognition across the lifespan—and why psychiatry's focus on neurotransmitters alone misses critical biological drivers of mental illness. Dr. Linus Abrams, a psychiatrist with 35 years of experience, reveals how endocrine dysfunction often underlies depression, anxiety, bipolar disorder, and postpartum mental health crises, and why symptom reduction without restoring full human flourishing leaves patients chronically unfulfilled. SSRIs elevate serotonin but reduce dopamine and norepinephrine, often causing emotional blunting or cognitive dulling despite symptom improvement—why distinguishing bipolar from unipolar depression is critical because antidepressants can trigger dangerous mood cycling or mixed states in bipolar patients.