Research out of Weill Cornell Medical College that was published in the journal Cell discusses a discovery regarding the part of the brain that helps guide the development of neural circuits. The findings may have implications for understanding of how disorders such as autism or other developmental disorders arise.
A major piece of brain development is the process of neurons becoming interconnected—creating what is commonly referred to as “neural circuitry.” In order to do this, neurons extend axons, which are like internet cables for neurons; they allow neurons to transmit information to each other. Axons figure out where to connect using “growth cones” located at the axon’s tip. The growth cones sense the surrounding environment and then determine the course the axon takes. This research discovered that the growth cones are able to conduct axon growth using embedded RNA molecules that tell the axon to move up, down, left, or right.
This particular study investigated neurons that follow the spinal cord and connect to the brain, which is a critical section of the nervous system.
The researchers found that the RNA found in the growth cones is “mostly silent,” and is only read at certain stages in the axon’s development. Once the axon’s growth is complete and the neural connection is finished, the RNA degrades and disappears. It is only when the RNA does not degrade that there are problems for neural connectivity because they continue to give movement instructions when none are required.
When the RNA does not degrade at the correct time, the result is faulty neural wiring. If the RNA’s signal remains active after it should have stopped, it can impede the delivery of new, critical instructions to the axons. According the study’s senior author, Dr. Samie Jaffery, professor in the Department of Pharmacology, “Understanding the basis of brain miswiring can help scientists come up with new therapies and strategies to correct the problem.”
Since children’s brains in particular have a high degree of neuroplasticity, it may be possible to reconfigure the miswired circuits, correcting the neural pathways and eliminating developmental disorders. This could have implications for treating disorders like autism, movement disorders, and more.