As an undergraduate at the Universidad Metropolitana, Marcos focused on the neural substrates of learning and memory, with an emphasis on models of obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD). During this time, he participated in two summer internships: one at the University of Pennsylvania with Dr. Seale, where he studied adipocyte function in the context of obesity and diabetes, and another at MIT with Dr. Tye, where he investigated neural circuits regulating palatable food intake. These formative experiences inspired him to pursue a PhD in Neuroscience. Now at the University of Pennsylvania working in the Hayes' lab, he aims to understand the role of amylin signaling in understudied brain regions, particularly the lateral dorsal tegmental nucleus (LDTg), in the regulation of food intake.