Kauê M. Costa was a Ph.D. student in Germany trying to understand how amphetamines cause hyperactivity when he noticed his mice were acting weird. The mice were genetically engineered to help researchers study dopamine in the brain, and they were unusually hyperactive. The amphetamines they were taking calmed the females but not the males. The mice were learning differently based on sex, and this divergence was scrambling his results.
Born in Amazonian Brazil, Costa is now an assistant professor at the University of Alabama at Birmingham, studying how animals learn. He’s applying new tools to neuroscience’s classic behavioral tests, food cues, mazes and lever pressing, trying to understand how the brain decides what information is important and should be stored and what can be thrown out. “We are constantly bombarded with, let’s say, a practically infinite amount of information,” Costa says. “What are the principles that determine what we learn and how we learn it?”
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His work suggests that dopamine is involved not just in helping us learn what is good and what is bad. Dopamine also plays a role in a more complex type of learning that helps us infer what’s next based on past events.
Whether dreaming of field biology or rising fast in neuroscience, Costa is guided by adventure. For this young person who once thought he would explore the Amazon, the brain is more complex, and thus more appealing, uncharted territory. He could have left the U.S. after finishing his postdoctoral fellowship, but even amid federal funding chaos, doing research in the U.S. is still “incomparable.” He teaches his students to follow their interests and their own minds—which now we understand a little better thanks to his pursuits.
This article is part of “The Young American Scientists,” an editorially independent project that was produced with financial support from Regeneron.

