Dr. Donna Calu
Associate Professor University of Maryland, Baltimore
Postdoctoral Researcher National Institute of Drug Abuse
PhD University of Maryland
As the child of two special education teachers, Dr. Donna Calu grew up listening to her parents discuss their work and the challenges facing their students. Little did she know, Donna’s eavesdropping on these chats would foster a longstanding fascination in psychology and behavior. Throughout her career as a neuroscientist, this interest has manifested itself in her studies of the brain. Now an Associate Professor of Neurobiology at the University of Maryland School of Medicine, Donna studies the neural basis of reward learning, particularly in the context of substance use, addiction-related behavior, and relapse vulnerability.
Donna began her undergraduate degree in biology at the University of Maryland, College Park with medical school in mind. However, her side job as a student teacher in special education with high functioning children with autism left her pondering the biological basis of behavior. Specifically, how did individual differences between students affect the efficacy of interventions like discrete trial training, a behavioral technique intended to optimize learning for students with autism? Hoping to find answers to some of these questions, Donna decided to apply for graduate school.
In her interviews for PhD programs, Donna was captivated by the expansive and diverse world of neuroscience research. She particularly recalls a moment from an interview with Dr. Geoff Schoenbaum in which she was hooked by the idea that drugs of abuse "hijack" the brain's natural reward system. She was mesmerized by this concept, which lasted long past the interview; she ultimately joined Geoff’s lab at the University of Maryland School of Medicine. Upon beginning her PhD research, Donna was delighted with the supportive environment at UMB, especially in her thesis lab. Working alongside then-postdoc Dr. Matt Roesch, Donna was able to successfully record dopaminergic signaling and overall activity from the amygdala. They found unidirectional changes in activity in the amygdala following changes in an expected reward. Specifically, regardless of whether the value of a reward unexpectedly increased or decreased, neural activity increased. Their findings highlighted the important role of the amygdala in attention and reward learning behaviors, which are crucial first steps to understanding the biological basis of dysregulated learning and motivation in addiction.
When thinking about her next step after her thesis defense, Donna considered taking a break from traditional benchwork science, especially because she had developed a rat allergy. Then, she was offered a postdoctoral opportunity at the National Institute of Drug Abuse by one of her mentors and committee members, Dr. Yavin Shaham. This position would allow her to continue working in addiction research using cutting edge optogenetics technology. She also knew the lab environment was supportive, and it didn’t hurt that NIDA was close to home. When she realized what a great fit the position was, she knew she couldn’t turn it down. She began a project studying the role of the prefrontal cortex in driving palatable food seeking, a food-based model of addiction relapse behavior, in rats. However, in optogenetics research, there is a lot of down time—waiting for cells to express the light-sensitive protein can take days to weeks—and during one of these lulls, Donna came across an interesting funding opportunity: the NIH Early Independent Scientist grant. Drawing from her PhD work, she formulated a research proposal to investigate the role of individual differences in reward learning to predict addiction relapse vulnerability in rats. To her delight and surprise, she was invited to interview at the NIH a few months later.
Despite a bumpy experience during her interview at the NIH where she briefly froze up during her presentation, Donna was awarded the Early Independent Scientist Award, which gave her funding for a 3-5 year non-tenure track position to start her own lab at the NIH. When she thinks about how she froze up during her interview, she feels lucky to have received the award, but also grateful for the attendees at her talk who gave her comforting nods to encourage her to keep going. That experience and the compassionate mentorship she received during her PhD and postdoc have greatly impacted Donna’s approach toward mentorship and flavor her advice to all early career researchers as they choose labs and institutions.
In her four years running her lab at the NIH as an Early Independent Scientist, Donna was able to build a solid research foundation studying reward learning and addiction relapse vulnerability in rats. The experience of starting her own lab, navigating the bureaucracy of institutional research, and the research program she constructed were invaluable when the time came to look for tenure-track positions. She ended up returning to the University of Maryland to set up a lab to continue the work she had started at the NIH. Specifically, she sought to investigate the neural basis of reward learning and its associations to addiction relapse vulnerability in rats by employing a class of behavioral paradigms known as “sign-and-goal-tracking” tasks. These types of tasks probe whether an individual rat is more sensitive to a cue for a reward (“sign”) or the value of the reward itself (“goal”). Previous research has found that relapse vulnerability is highly linked to sign-tracking behavior, or a rat’s tendency to attend to and learn the cues that predict a reward, even before the rat is ever exposed to an addictive substance. Relapse vulnerability is less severe in rats who are more sensitive to the absolute value of a reward – i.e. “goal-tracking” rats. Donna’s lab has used electrophysiology, optogenetics, and fiber photometry to identify several structures in the reward learning system—the amygdala, striatum, insular cortex, and the neural connections between them—that encode some of the differences between sign- and goal-tracking rats. Going forward, she intends to continue to investigate the neural basis of these different behavioral phenotypes, with special attention to sex differences, RNA expression, and cannabinoid signaling.
In addition to leading her lab at the University of Maryland, Donna also serves as the director of the Graduate Program in Neuroscience. As director, she is dedicated to attracting and retaining talented young scientists by nurturing a sense of belonging in the neuroscience community at UMB. “Training should be a positive experience,” she says, and it is very important to her that students see careers in STEM fields and academia as viable and rewarding. By replicating her own experiences of supportive mentorship to create an environment that engenders creativity and innovative science, Donna is setting up the next generation of scientists for a career as successful as her own.
Find out more about Donna and her lab’s research here.
Listen to Rianne’s full interview with Donna on May 5, 2023 below!
