A person’s mindset when they are in a soft state, similar to feeling high or drunk without even intoxicating one’s self.

Often, people in puppy brain act small and soft for a while, and often it lasts for a minute or two. But it simply depends on the person.
My Puppy Brain can’t handle all of this...”
“Don’t mind them. They’re in Puppy Brain”
by Deku’s CuddleBug January 2, 2021
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When a person is obsessed with all dog breeds, and starts cooing over any dog they see walking the streets.
I have such Puppy Brain - I want a dog so badly.
by taiwks January 22, 2014
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