Yale Study Uncovers How Brain Wiring Begins Before Birth

Researchers at Yale say they have uncovered how the brain begins to wire itself during early development, long before experiences or sensory inputs like sight come into play. The study, published this month in Science, reveals that brain cells start forming networks based on spontaneous cellular activity, following the same principles observed in later development stages, where cells that fire together wire together.

"One of the fundamental questions we are pursuing is how the brain gets wired during development,” Michael Crair, co-senior author of the study and the William Ziegler III Professor of Neuroscience at Yale School of Medicine, said in an article posted on Yale's webiste. “What are the rules and mechanisms that govern brain wiring? These findings help answer that question.”

To explore this process, the researchers focused on mouse retinal ganglion cells, which extend from the retina to the superior colliculus, a region in the brain responsible for processing visual information. The study involved measuring the activity of a single retinal ganglion cell, observing the anatomical changes it underwent during development, and monitoring the activity of surrounding cells. These experiments were conducted on neonatal mice that had not yet opened their eyes, ensuring that sensory experience did not influence the results. The researchers found that in the absence of visual experience, the cells began to coordinate their activity spontaneously. This spontaneous activity led to the formation of neural circuits, effectively wiring the brain before external stimuli could guide the process.

Read the full article.