My name is Meg Gladieux, I am going into my third year at Penn, and I am a double major in Cognitive Science and French and Francophone studies. My academic and research interests lie in children’s development, particularly in how environmental influences shape cognitive development and implications for social policy. This summer, I worked with Dr. Jianghong Liu, whose research focuses on early childhood exposures and brain and behavioral outcomes in children and adolescents.
What is your summer research project?
My summer research focused largely on an independent literature search that integratively examined the current work in the fields of community and environmental health regarding cumulative outcomes of toxic environmental exposures and social disadvantage on children’s cognition. I examined journal articles across several databases to understand the current state of the field and to identify gaps in understanding of this very important dimension of community health. Through this process, I particularly concentrated on two key environmental exposures: air pollution, including PM2.5, PM10, and PAH, and lead exposure. I also analyzed a few recent publications dealing with secondhand tobacco smoke as well as other common household toxicants affecting children, including pesticides and PBDE. I focused on these exposures because they are the most prevalent exposures in children, with high risk in children’s environments through nearby industrial sites, heavily trafficked areas, homes, particularly homes with older infrastructure, schools, and other buildings and background exposures.
I cross-searched these key childhood sources of toxic exposure with multidimensional indicators of adversity including material hardship, parental education, family dynamics, socioeconomic status, neighborhood conditions, and exposure to violence and trauma. While independently each toxic physical exposure and social exposures are associated with adverse cognitive outcomes, particularly relating to school performance, recent studies seem to indicate a cumulative effect when children encounter both types of environmental exposure. I developed a framework for thinking about cumulative environmental exposures within different domains of children’s holistic environments. The magnification of negative cognitive outcomes for children experiencing both environmental toxicity and social adversity is through prolonged toxic stress, in which there is a prolonged stress reaction in the brain due to both external biological and psychosocial factors and internal autonomic stress responses to the external world. These prolonged stress responses interfere with healthy cognitive development, increasing the likelihood of cognitive difficulties in childhood and beyond.
What are the implications of your research?
Thinking about policy and practical implications was a really big part of my work this summer. It’s important to systematically collect evidence that a problem exists, but ultimately, the goal of research is to figure out ways to solve problems. If we know that children facing more adversity and hardship are at higher risk of toxic environmental exposures and that these exposures actually amplify the negative effects of one another, it becomes even more vital to protect these vulnerable children from these risk factors both in their physical environments and social environments. The mechanism for the relationship between physical and psychosocial exposures contributing to toxic stress is multifaceted and still poorly understood. It is associated with neurotransmitter disruptions and inflammatory responses that hinder brain development. In fact, in MRI studies, we can see physical differences between the brains of children who have experienced high levels of toxic stress and those who have not.
This ultimately demonstrates that not only are vulnerable children more likely to be encountering the toxic environmental exposures, but their adverse social environments actually make the impact of those environmental exposures worse. Environmental pollution and overall climate change are having the biggest effects on disadvantaged communities, particularly the children within them. Mitigation of environmental hazards is thus most vital in the most poverty-stricken communities. Improving building infrastructure, increasing educational initiatives, and preventing further air and lead pollution from industry and construction through policy are possible first steps. Ultimately, protecting children through cultivating safe and loving holistic environments is the best way to ensure healthy development. Several promising recent papers suggest that increasing support within schools for children at high risk for exposure to toxicants in their homes and neighborhoods and increasing access to safe greenspaces may act as protective mechanisms that mitigate the impact of toxic stress (McCrae et al., 2021; Aerts et al., 2018).
What new skills have you gained through your research?
This summer, I didn’t only have the opportunity to work on my own independent project, but also contributed broadly to much of my mentor’s other work and ongoing projects. In addition to developing my own critical thinking skills, independent thought, and creativity in scientific inquiry, I have also been able to take part in several other projects through supporting roles. I have helped edit several manuscripts and prepare them for publication. I have also gone through the process of submitting several papers to journals as well as making edits and addressing the comments of peer reviewers. Additionally, I have been able to support my mentor in preparing peer reviews and providing suggestions on other manuscripts that are in production related to environmental and community health. These experiences gave me invaluable insight into the overall research process beyond data collection, inquiry, and literature review.
Through my research and overall experience in STEER this summer, I feel that I have gained so many skills that I will carry with me throughout my education, into further research, and toward my future career. I have become skilled at literature synthesis as well as citation management. I have learned how to take a collection of papers and draw connections across them to find new insights and identify current gaps within the current field. I have also become extremely proficient in navigating databases and sorting through extensive libraries of research to pick out the articles that are the most relevant to the problem I am researching. Finally, I have learned a lot about community health and participatory action research in community environmental work. Especially in studying people and the real-life effects of their environments on their well-being, research must prioritize inclusivity of community needs.