Dr. Trevor Hamilton has helped to build MacEwan’s zebrafish lab from the ground up, and has used it to make groundbreaking strides in neurological research. The 2024 Dr. Sherrill Brown Distinguished Research Award recipient studies zebrafish – after rodents, the most common animal used in neuroscience research – to look at anxiety, pharmaceuticals and the effects of climate change.

Here, the psychology professor discusses what sparked his interest in this research, his dedication to helping students find their passion and where he’s set his sights next.

Why zebrafish?

When I started at MacEwan, my background was in cellular neurophysiology. There's no way that I could do that type of research here, because it relies on rodent facilities that cost millions of dollars of infrastructure. At the time, zebrafish were becoming an important model organism, and that was something realistic that we could bring to MacEwan. We started off doing basic memory and pharmacological tests that students were very interested in, and that ended up in some great publications.

You were a part of getting the designated zebrafish lab here on campus. What was it like starting up the lab and seeing it expand over the years?

Dr. Melike Schalomon and I started that zebrafish lab from scratch. Before we had volunteers, Melike and I came in every weekend and every holiday. We had to do all the water changes, the fish feeding, the husbandry, all in a little space down the hall. In our super-cool new facility, the water is automatically changed, and we have an animal care technician whose team does all of the feeding and aquarium maintenance. We started off with one motion-tracking software system and now we've got three. And we’ve got this exciting new system called DanioVision that allows us to record and study the behaviour of 96 larval zebrafish at once. And the lab isn’t just ours – it's a facility for all of MacEwan. 

You've kind of covered a lot of ground in studying zebrafish – from micro-dosing with LSD to the effects of infrasound on anxiety. How do you decide what to focus on next?

It's a combination of what is interesting for myself and for my students, what is scientifically relevant and what is going to help my students progress in their careers. If I have a research topic that is an up-and-coming or trendy avenue, it's going to help my students out in terms of having them present this work at conferences and write scientific manuscripts. If there's a topic that's less interesting or relevant to the scientific field and people in general, the students may not have as good a chance.

Why is it important to include students in your research?

I like the enthusiasm and energy they bring. I don't have time to do all the research myself anymore, and students can be trained efficiently and produce scientifically important data within a relatively small amount of time. It's really fun seeing students progress, learn, think through scientific problems, present their work and become experts. I’ve published papers with 32 different MacEwan students who have worked in my lab. 

What is something you've studied that you found the most interesting, or something that has local relevance?

When looking at the effect of elevated carbon dioxide on zebrafish we saw that, as we increased the amount of carbon dioxide in the water, there was a completely different response in behaviour that wasn’t in any existing literature. We found this very bimodal effect: some doses really increased anxiety, other doses decreased anxiety, and the middle dose didn't do anything in terms of the behavioural responses we were measuring. There are implications when it comes to climate change – the more carbon dioxide put in the atmosphere, the more goes into oceans, streams and rivers and the more effects we will see. Zebrafish are freshwater fish, so these findings are more relevant to freshwater systems like the North Saskatchewan river than to the ocean. 

What's next in your research?

We're currently trying to selectively breed for high and low anxiety in zebrafish. Down the road, the goal is to come up with a model of a generalized anxiety disorder in fish. If we can have this model of high anxiety in fish, we can see if there's a different impact of certain drugs on high- versus medium- versus low-anxiety groups, which is important for clinicians to understand.

What did it mean to you to receive the Dr. Sherrill Brown Distinguished Research Award? 

I was very honoured. It made me very proud of all of the students who've contributed to my research over the last decade, because it was really a lot of their blood, sweat and tears (so to speak) that produced the data that has led to a lot of great science.