Mailbag XL: Is Fear a Neurotransmitter? | Fear, Brain Chemistry, Neurotransmitters, Amygdala, Dopamine, and the Neuroscience of Emotion

The Observable Unknown · Sep 2, 2026 · 6m

Is fear a neurotransmitter?

Can an emotion travel through the brain like dopamine, serotonin, glutamate, or norepinephrine?

Or is saying that “fear itself can become a neurotransmitter” a poetic metaphor that crosses a scientific line?

In Mailbag XL of The Observable Unknown, Dr. Juan Carlos Rey responds to listener Margaret R., who asks for clarification about a haunting phrase from an earlier Interlude:

Is fear literally a neurotransmitter, or was that metaphorical language?

The answer is clear.

Fear isn’t a neurotransmitter.

But understanding why reveals something far more interesting…