Why response inhibition research presents unique challenges for unimodal BOLD-fMRI

Response inhibition is one of the most important control processes in the human brain. The study of the basic neural mechanism(s) underlying response inhibition has produced some of the most-cited empirical work in cognitive neuroscience to date, with a large portion of the most influential work relying on unimodal BOLD-fMRI. More than 25 years after the first fMRI studies of response inhibition, new work using the method to investigate its basic neural mechanisms still appears with regularity. This article seeks to outline why fundamental questions regarding the basic neural mechanism underlying response inhibition still remain unresolved, why new unimodal fMRI work often produces seemingly confusing results, and why experimental comparisons that are vital to understand response inhibition are almost never found in fMRI research. I argue that due to a unique combination of factors - the temporal resolution of BOLD-fMRI, the fundamental behavioral dynamics of laboratory response inhibition tasks, and the specific properties of the underlying neural circuits - the study of response inhibition presents a greater challenge for fMRI than other fields. I will then outline two potential avenues through which the method can remain valuable despite these limitations.