[The amygdala and it's neurotransmitter systems, he corrects gently between sentences. Unable to write upon a chalkboard, he decides to interject, to educate. Because when any student of his calls the amygdala a "lizard brain" they fail the class.]

Correct. Though GABA is poor at crossing the blood-brain barrier. I suppose one would need to influence the enteric nervous system through the gut-brain axis. Magnesium and apigenin could work. Quercetin and kaempferol too now that I think about it...

[He continues thinking. One cannot simply carry tons of leafy greens away from the store without provoking suspicion.]