PAGE 6 OF 6
Studies such as these are revealing new clues about how normal brains and nervous systems develop as an embryo matures. But the research may also illuminate causes of disease. Problems in wiring can crop up, resulting from genetic miscues or other causes, as an embryo develops. Growing evidence suggests that this kind of faulty wiring may underlie neurological disorders such as schizophrenia. Understanding how and why wiring gets fouled up during development might lead to ways to correct the problem before it's too late.
In addition, some of the strategies that help an embryo set up a working nervous system might also keep the nervous system in proper order during adulthood; defects that develop later in life could contribute to neurodegeneration. Finally, one way to fix a damaged nervous system might be to reactivate the processes an embryo uses and spur the body to regrow parts of the system.
The new insights about how neurons find their path, avoid themselves, and establish appropriate connections reveal many of the instructions for weaving the intricate tapestry of the nervous system. “We already know a lot of the molecules that are involved,” says Tessier-Lavigne, “but these studies highlight the fact that many additional players remain to be discovered.” Many of the overarching navigation strategies likely remain undiscovered as well, he suggests. Further efforts will provide even more nuanced views, not only of the journey that each neuron takes to create a working nervous system but also of ways to preserve the wiring's integrity and to keep brains healthy.