Discover how Henry Dale's four scientific criteria revolutionized our understanding of neurotransmitters, from proving chemicals carry brain messages to revealing emotions as molecules flowing through our entire body.

We're not just electrical beings—we're chemical beings too. Emotions aren't just happening in our heads; they're literally molecules flowing through our bloodstream, acting as a giant communication network for the entire body.
Dale’s criteria to define a chemical as a “putative neurotransmitter”


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