Lab-Grown Neocortex Models Mimic Early Brain Organization

During brain development, specific areas form with unique functions like movement, vision, memory, and language. Scientists believe that chemical signals guide these cells in determining where they should be located, contributing to the differences between areas at the front and back of the cerebral cortex. This process, called arealization, is crucial for understanding brain function and disorders.

Traditionally, creating lab-grown human brain tissue with a defined regional identity has been challenging. However, researchers at the University of California, Irvine, have developed a novel method to engineer human brain tissue in the lab with characteristics of either the front or back of the developing cerebral cortex. This breakthrough allows for studying neurodevelopmental disorders in greater detail.

The team used human stem cells to create neocortical organoids that adopt the identity of either the front or back region by introducing specific chemical signals. By analyzing more than 200,000 cells, the scientists found that the organoids replicated molecular characteristics associated with different prenatal human regions. For instance, they examined how fragile X syndrome, a genetic condition, affected brain development.

In organoids derived from individuals without the condition, the distinct molecular differences between front and back regions were evident. Conversely, in organoids modeling fragile X syndrome, these differences were diminished. This finding aligns with other research on donated tissue from people with autism, suggesting a potential developmental process to investigate further.

The new approach could help researchers explore how neurological and neurodevelopmental disorders impact different brain regions during development. The platform also contributes to the broader efforts to develop human tissue-based models that can complement animal studies.