They can be up to two inches long, typically live in streams, canals, ditches and ponds and are named for their uniform, colorful horizontal blue stripes on the side of their bodies. The zebrafish is not only a popular aquarium fish, but it’s also an important model organism in scientific research.
In fact, this tropical freshwater fish is the focus of Assistant Psychology Professor Rachel Blaser’s research.
Blaser’s work involves using zebrafish to better understand how the human brain works. By understanding how their simple brains learn about the world, she explains, we can gain a better understanding of how the mind works and how humans learn.
“What I’m most interested in studying is how we make associations, which I think is at the heart of cognition,” she said.
Blaser talks with enthusiasm about zebrafish. “They are a much more convenient genetic model than rats and mice. One can do good genetic research with mice, but it takes longer and is more expensive, and it’s more complicated in general.” Blaser explains that using zebrafish is a much more advantageous way of doing research because the fish are cheaper, smaller, and they reproduce rapidly.
Blaser’s current research focuses on fear and anxiety in fish. She says zebrafish are similar enough to humans in the way that their brain and neurochemistry works. She adds it’s easy to look at the genes of the fish and see how genes affect behavior and cognition. And in turn, scientists can use that information to understand what genes are relevant for human disorders. Blaser maps the fish and records their behavior with a video tracking system wired to a computer in the lab. From there, she records what happens when the environment is manipulated with different variables. Blaser can then extract the data files and conduct data analysis.
“The hope is to find some of the neural pathways and genes involved in things like drug addiction, autism, anxiety disorders, etc.,” she said.
Blaser also co-directs the Summer Undergraduate Research Experience program (SURE) which provides summer stipends for students who want to do research on campus with a faculty mentor. Students apply for a SURE grant by preparing a short research proposal in collaboration with their proposed faculty mentor. This year there are 19 SURE students.
“It’s a fair number, but never as many as we would like,” she said. “We got 49 applications, but we could only fund about half of them.”
SURE awardees are expected to present their research at the annual student research conference, Creative Collaborations, in the spring following their summer research.
Kelly Goldsteinholm, an incoming junior and psychology major, received a SURE grant to work on zebrafish this summer. Both Goldsteinholm and Blaser are working on a drug study that looks at the effects of alcohol, caffeine and taurine on behavior. The hope is to be able to find new drugs for the treatment of anxiety disorders or other kinds of disorders.
“I hadn’t really heard of any research being done with zebrafish before I started working in the lab, but the more I heard about it from talking to Rachel, the more interested I got,” Goldsteinholm said. “Rachel has without a doubt been an amazing mentor. She has presented me with many amazing opportunities such as helping her with book chapters and journal articles on zebrafish. I feel so lucky to have been exposed to them.”
In the three years she’s taught at USD, Blaser describes her experience as wonderful.
“It’s kept me really busy, the students are fun, and the school has been very supportive of my research,” she said. “It’s been excellent.”
By the end of next year, the Department of Psychology is hoping to start a new major in behavioral neuroscience.
— Leslie Luna
Photographs by Colin Gilbert