ALPHABETICAL BRAIN VOCABULARY Flash Card #73 - Details WHAT ARE YOUR "SEROTONIN NEURONS" AND WHY ARE THEY SO IMPORTANT? Your SEROTONIN NEURONS play a significant role in the regulation of your feelings (moods), sleeping, learning and the squeezing or compression ("constriction") of your blood vessels, which is known as "vasoconstriction." Biochemically, they are derived from tryptophan and they are primarily found in your gastrointestinal (GI) tract (up to 80%), your blood platelets, and in your central nervous system (CNS) just as they are found in all animals! At normal levels, these neurons contribute to your feelings of well-being and happiness, but at LOW LEVELS, they influence the ionic action of your SYNAPSES by causing DEPRESSION. The typical source of your SEROTONIN NEURONS is along the "midline" of your BRAINSTEM. They are distributed or "projected" DOWNWARD into your spinal cord and also "projected" UPWARD into all regions of your brain. Book Source = (Your Brain on Food, pages 23-24) and Online = Wikipedia Return to #73: SEROTONIN NEURONS or BRAIN FACTS MATRIX