Jack and Pelphrey provide a systematic review of neuroimaging studies in understudied populations within the autistic spectrum, focussing specifically on those with minimal verbal ability, intellectual disability and developmental regression. Despite accounting for nearly a third of the autistic spectrum, the number of studies focussing on these populations is extremely low. This review highlights a critical need for further neuroimaging research on these populations, and provides practical suggestions for overcoming the challenges posed by it. In this commentary, I discuss some of the theoretical questions that arise from the review, on the conceptualisation of the autistic spectrum as well as on optimising experimental design and analysis.