Cross-fostering Influences the Effects of Air Pollution and Prenatal Stress on Social Behavior

Cross-fostering Influences the Effects of Air Pollution and Prenatal Stress on Social Behavior

Jason Zhang

My research project examined possible mechanisms related to the effects of air pollution and stress during pregnancy on the later life social behavior of mice. Previous epidemiological work has shown that mothers exposed to high levels of diesel exhaust pollution during pregnancy were more likely to have children who developed autism spectrum disorders. A similar association was found for mothers that experienced significant psychosocial stress during pregnancy. Research evaluating the effects of this form of air pollution and stress in mice has shown that they are also associated with changes in the gut microbiome and the interactions between the immune system and the brain. My Visible Thinking research project sought to evaluate whether air pollution and stress might be causing changes in the gut microbiome that ultimately lead to social behavior deficits that are characteristic of autism spectrum disorders.

Through my project, I was given an opportunity to build on the foundations of knowledge that I had previously acquired through my undergraduate coursework. Neuroimmune interactions and the gut microbiome are profoundly complex, sensitive biological systems, and the difficulty of studying how they might contribute to our daily lives is only compounded when trying to study their effects on something as nuanced as social behavior. I was first drawn to neuroscience by questions of how biology impacts abstract, yet essential parts of our lives, like how we feel, how we uniquely perceive the world around us, and why, biologically, our social behaviors change through different life experiences. When I first thought of these questions, my surface understanding of neuroscience led me to think that, of course, it has to be changed in the brain—no more, no less. I didn’t realize how important other biological and cognitive systems were for guiding, molding, and orchestrating brain development and plasticity until I took a class with Professor Staci Bilbo on behavioral neuroimmunology. I knew my Visible Thinking project was something I would be interested in because, after this class, I was fascinated by how changes in the immune system and other, to me, similarly unexpected parts of the body could have significant effects on our brains, behaviors, and experiences of the world. While I had previously been engaged in cognitive sciences and looking at the brain at the resolution of fMRI, I knew after taking this class that I wanted to do more to understand how changes in behavior occur at the level of cellular mechanisms. Professor Bilbo was supportive of my interest and generously allowed me to begin volunteering in her lab, and that was what ultimately set me towards pursuing this thesis and Visible Thinking project now almost two years later.

I gained valuable experience applying this new perspective and learning what research tools were available to answer questions about neuroimmune interactions and the gut microbiome. It was also my first time working with an animal model, personally scoring mouse social behavior, and becoming familiar with the limitations and benefits of evaluating social behavior in non-humans. I realized how much more time and resources animal research required. It’s easy to read about design pipelines and theorize about how you’d like to evaluate different ideas or improve past experiments, but the amount of time and detail that goes into bringing those ideas to fruition was something that I hadn’t ever appreciated. I am very grateful to my research mentor, Dr. Caroline Smith, for helping me through this learning process.

Overall, my research project was exciting and engaging, giving me opportunities to learn while exploring something I was curious about. There is so much more to the biology behind how we go about, see, and enjoy our daily lives than just the neurons in the brain. From our immune systems to the microbiome in our guts, and even characteristics of our environment like the air we breathe and the challenges we experience day in and day out, it seems fair to say that everything seems to have an effect on how we live, and therefore could have an effect on our brains as well. There is so much more to continue exploring, and I’m looking forward to continuing to engage in neuroscience research in the future.