Rain pours down on a group of Notre Dame students as they trudge through the South Bend streets, carrying buckets and shovels. Pushing a wheelbarrow full of mulch, they are working to help combat lead poisoning in the community. The weather is dreary, their shoes soaked through, but laughter cuts through the downpour as they make light of the moment, recalls Mason Cohen ’26.
It’s a scene the neuroscience and behavior and Latino studies major knows well. During Mulch Madness, an annual lead poisoning prevention project, he and his friends discovered that community service is meaningful but can also be fun, even if a bit challenging.
Cohen was involved in the preparation for the 2026 iteration of Mulch Madness, originally started by a Notre Dame Class of 2022 alumnus Kyle Moon and members of the Notre Dame Lead Innovation Team (ND-LIT) in 2018.
“Mulch Madness helps to fight lead poisoning here in South Bend. There are many studies showing how detrimental lead exposure is to neurodevelopment. It's both a prevention and an awareness initiative,” said Cohen.
As this year’s project leader, Cohen spearheaded the effort to provide South Bend residents in the Near Northwest Neighborhood free mulching services (which helps mitigate lead exposure by encasing the metal in the soil) as well as connect them with resources through the City of South Bend government for lead-related home repairs. The event took place on March 28, 2026, during Back the Bend.
Mulch Madness is also closely tied to Marya Lieberman's lab in the Department of Chemistry and Biochemistry, which uses lead testing kits to test residents’ soil samples for lead levels. Lieberman and Heidi Beidinger-Burnett, professor of the practice in the Eck Institute for Global Health, have been the faculty support system for Cohen in the project.
Cohen took a neurotoxicology class with Associate Teaching Professor Rachel Branco, and learned more about the Flint, Michigan water crisis—a regional tragedy involving lead poisoning. Cohen’s mother grew up in Flint and lived there for many years, so the topic resonated deeply with him.
“The crisis in Flint is the exact kind of situation I hope to prevent in marginalized communities here in South Bend, especially because it has been found that a lower socioeconomic status exacerbates the risks associated with lead poisoning,” he said. “Local residents and their children are at risk to this toxin and often unaware of this invisible threat.”
In addition to his work with Mulch Madness, Cohen has dedicated much of his time over the past four years to many different types of research. As a first-year student, he worked as a research assistant in the Attention, Memory, and Perception lab of Professor of Psychology Bradley Gibson. Continuing his psychology research, Cohen joined Assistant Professor of Psychology Jenny Padilla’s Latino Adolescents, Siblings, and Families lab, where he interviewed participant families in Spanish to collect data for the lab and to improve his research capabilities and Spanish language skills.
During the summer after his sophomore year, Cohen participated in a biostatistics research program at the University of Pennsylvania, where he was mentored by Professor Nicholas Seewald, a 2013 Notre Dame graduate. Cohen presented his research poster at the Leadership Alliance Conference at the end of the summer and also won an award for presenting his work at the Annual Biomedical Research Conference for Minoritized Scientists in November 2024.
Back at Notre Dame, he worked alongside Diane Lane, assistant teaching professor in the biological sciences department. Hoping to pursue a career in psychiatry or neurology, Cohen started to work on an independent review paper, synthesizing literature and writing an opinion about that literature.
During his senior year, Cohen continues to work on his review paper, researching the rehabilitation potential for the emerging class of GLP-1 agonist medications—developed and popularized recently for weight loss—to treat struggling addicts. His goal is also to understand and further explain the mechanistic similarities between classical drug addiction and impulse control disorders, which have historically been considered distinct from one another. Lane described Cohen’s research in glowing terms.
“I cannot take any credit at all [for Cohen’s success],” Lane said. “I've just been here guiding him. The content of the review paper has been his ideas because he's so amazing.”
Lane connected Cohen to researchers at Weill Cornell Medicine, where he completed his junior year summer research internship in a biological psychiatry lab. He worked under the principal investigator Conor Liston, investigating depression through the use of mouse models. Cohen performed so well that Dr. Liston has invited him to rejoin his research lab for post graduation work as a full time research technician.
“Dr. Liston’s lab is enormous, so to notice an undergrad that's visiting in a summer position speaks volumes to how great Mason is,” Lane said.
Cohen hopes to attend medical school after his post-grad work at Cornell. “My goal is for research to always be a part of my career, even as a practicing physician,” he said. “Even though I aim to remain active in academia, and I believe that medicine relies on science for the future, it must also be put into practice in the present, and that's what I'm the most passionate about.”
In addition to psychology and neuroscience, Cohen has demonstrated an interest and commitment to the Latino community and culture. Early in his time at Notre Dame, his goals of simply studying abroad and improving Spanish fluency grew into a larger interest. Cohen recognizes the extensive support and mentorship he received from Karen Richman, the Director of Undergraduate Studies for the Institute for Latino Studies (ILS), which welcomed him to the ILS community and allowed him to grow in coursework outside the College of Science.
He spent a summer abroad in Chile, and during junior year, he was able to study in Toledo, Spain, taking classes that counted towards his Latino studies major.
While in Toledo, he was given the opportunity to participate in an internship class where he worked in a multiple sclerosis clinic for eight hours a week. Communicating exclusively in Spanish, he shadowed physical, speech, and occupational therapists as well as independently led patients in self-procured cognitive and physical wellness activities.
While in South Bend, he volunteers at the Sister Maura Brannick Health Center, a clinic in South Bend which serves a primarily Latino and immigrant population. “Volunteering at a clinic that's trying to bridge disparities is meaningful work,” said Cohen.
Working at the Sister Maura Brannick Health Center has further confirmed his desire to become a physician and strengthened his Spanish skills. “I see how the doctors often communicate through medical translators and hope I will be able to speak directly with not just one group of people but two,” Cohen said.
“I've always been influenced by Spanish and been surrounded by Latino communities. It always made sense to me that I would grow this part of my communication skill set and have the chance to be a part of something that I wouldn't have been able to be a part of otherwise,” he said.
Cohen has devoted his undergraduate years to serving others and pursuing research that directly aims at helping those in need.
“He is the biggest proponent of community inclusion of everyone and helping others. When you're around him just for a few minutes, you already feel included and welcome,” Lane said.