Insight into the rapidly developing brain in utero is scarce. Fetal functional magnetic resonance imaging (fMRI) is a technique used to gain awareness into the developmental process. Previous auditory task-based fMRI studies employed an external sound stimulus directly on the maternal abdomen. However, there has since been recommendation to cease doing so. We sought to investigate a reliable paradigm to study the development of fetal brain networks and postulate that by using an internal stimulus, such as the mother singing, it would result in activation of the fetal primary auditory cortex. Volunteers carrying singleton fetuses with a gestational age of 33-38 weeks underwent two stimulus-based block design BOLD fMRI series. All of the nine fetal subjects analyzed had activation in the right Heschl’s gyrus, and seven out of the nine fetal subjects had activation in the left Heschl’s gyrus when exposed to the internal acoustic stimulus. Ultimately, this internal auditory stimulus can be used to analyze the developing fetal brain
