September 11, 2025
MCLA psychology professor Dr. Tom Byrne, adjunct professor Eric Denette, and recent graduates Ryan Taylor ’25 and Ellie Walter-Goodspeed ’24 have co-authored a paper that was recently accepted for publication in the journal Behavioural Pharmacology.
The paper, “The effects of Xylazine on Locomotion and Motor Behavior in a Planarian Model,” stemmed from discussions held in Dr. Byrne’s Drugs and Behavior course, where students often bring in news articles relating to the coursework.
Xylazine, used as a sedative in veterinary medicine, has been in the news lately as it has increasingly been found mixed with the street drug fentanyl. Public health concerns were raised due to the possibility of overdose, as rescue drugs such as naloxone do not work on xylazine. The drug also seems to cause severe skin lesions, which can lead to serious tissue damage and possible amputation, possibly because xylazine limits blood flow and slows down healing.
In the lab, Byrne, Denette, Taylor and Walter-Goodspeed ran experiments using planarians (tiny flatworms). The finished paper describes two of their experiments: determining if planarian behavior is susceptible to xylazine, and if those effects were orderly. “At higher doses, we noticed complete sedation, and they stayed sedated for a long time,” said Byrne, “but if we stimulated them, they moved around normally again.”
Although Byrne and his students do not publish as frequently as labs at large research universities, he said it’s not unusual. “I work with students in the lab every semester,” he said, “and sometimes we find something worth sharing at a conference or in a journal.”
“The best thing about this was the opportunity to have an academic idea and see it come to fruition,” said Taylor, a psychology major and biology minor. “I was foreign to the experiments going in, but with Dr. Byrne’s guiding hand, time and effort, we deduced our procedures and put it together in a manuscript that we were able to send out for publication. It changed my outlook on what I’m going to do the rest of my life; I’m now pursuing a Ph.D. in behavioral pharmacology or psychopharmacology.”
The group’s paper is currently in the peer review phase, and will then be scheduled for publication.
