Our main line of research focuses on theoretical and methodological contributions to the field of bilingualism and cognition. Several researchers have suggested that learning and using a second language requires domain-general executive functions (e.g. inhibition, task-switching, working memory), and many have shown that bilinguals outperform monolinguals on tasks that tap into these processes. However, recent behavioral studies and meta-analyses reporting failed replications have called into question whether or not bilingualism leads to changes in domain-general executive functions. Our past and current work has been to understand why sometimes studies find these differences, and others do not. Rather than examining the “yes” or “no” dichotomy that dominates the field, we push researchers to consider when, rather than if, bilinguals outperform monolinguals on executive function tasks (e.g. Grundy, 2020). We do this by examining the variability of multilingual experiences. Our work also heavily focuses on understanding the neural and cognitive mechanisms underlying these performance changes. We use a combination of behavioral and neuroimaging techniques to understand the neuroplasticity that eventually helps to prevent cognitive decline associated with age.