Understanding the Neurobiological Components of Neurodevelopmental Disorders

In this chapter, we focus on the neurobiology of intellectual and developmental disabilities. We first approach the topic by providing the reader with a broad understanding of neurobiology and neurodevelopment. While it is well known that the cellular and molecular components underlying development are complex and tedious, so too are the complex circuit formations that develop and continue to refine through a product of intrinsic signaling as well as by way of additional external exposures and experiences across development. To better understand how unique exposures may differentially impact developmental processes and skew system development, we first tackle how neurobiological processes typically develop across time. In this chapter we give a broad overview of typical neurodevelopment, highlight key neurobiological components that are involved in neurodevelopment, and then turn to how atypical trajectories may arise. Additionally, an overview is provided of the tools at our current disposal that allow us to measure neurobiological processes, giving insight at the cellular, circuit, and ultimately, behavioral level. Wrapping up the chapter, we explore in depth our current understanding of two specific neurodevelopmental disorders associated with intellectual disability.