The big questions

Despite everything we know about the processes of brain development, neuroscientists are still trying to unravel the details of the biggest question of all: how exactly does a tiny collection of embryonic stem cells produce a functioning human brain containing around 100 billion correctly wired neurons?

We have come a long way from discovering how stem cells function. Neuroscientists now have a working knowledge of the fundamental processes underpinning brain development, including neuron birth, differentiation, migration and the wiring of complex circuitry. We also know that when these processes fail, devastating consequences may impact a person.

But we do not know how all the intricate and essential processes needed to build a functioning brain are precisely coordinated during development. What guides the integration of molecular and cellular activities – within genetic and environmental influences – to ensure each process occurs how, where and when it needs to?

We also have much to learn about why genetic and environmental risk factors can adversely affect development in some people and not others. For example, most babies exposed to prenatal maternal smoking experience no developmental problems, but in a small minority, it can cause growth retardation and later psychiatric conditions.

Similarly, we do not understand why exposure to the same environmental risk can produce different developmental outcomes, causing autism in some and not others. What makes some embryos resilient to adverse environments and others not? And why do the same risk factors produce different outcomes?

These are some of the questions QBI researchers are striving to answer.