Brain organoids: a new tool to understand the human brain


Let us agree on this: we do not know how the human brain is formed. Thus, we do not understand how it works. For years, the early stages of human brain development were challenging to investigate. Due to limited access to the human brain in utero, scientists have relied on indirect techniques, such as ultrasound imaging, abortus material, and animal models. Most of the neuroscience research was (and continues to be) done in animal models. However, it is a mistake to think that a rodent brain is a smaller version of our own. Each species has evolved unique brains to cope with individual physiology and lifestyle. Consequently, we know more about the mouse brain than ours, and we collect evidence of translational failures of treatments for neurologic conditions. In addition, none of the other models (eg, ultrasound, postmortem tissues) allow scientists to experimentally study the human brain. Our knowledge of human neurodevelopment is therefore incomplete, with limited information on the stages of its creation and especially of pathologic conditions. Fortunately, new possibilities emerged when scientists first created human brain organoids in a dish1. These miniaturized versions of the human brain can complement traditional models and improve our understanding of the brain.