British scientists have shown for the first time how our brain wiring develops in the first few months of life and say their findings will help in the understanding of a range of brain and psychiatric disorders.
Using a new imaging technique, researchers from the Institute of Psychiatry at King's College London scanned babies brains to monitor the formation of insulating layers around nerve cells.
They found that by the age of nine months, the process -- known as myelination and vital for normal brain function -- was visible in all brain areas and in some regions had developed to a near adult-like level.
We already know that insulating myelin sheaths form the cornerstone of our neurodevelopment. Without them, messages to and from the brain would be in disarray, said Sean Deoni, who led the study, published by the Journal of Neuroscience.
By understanding exactly how myelin develops and when this process breaks down, we hope to be able to tailor treatments for vulnerable patients, such as premature babies, and understand what differentiates those that develop normally from those who have some delay or disability.
Damage to the myelination process is thought to contribute to a range of neurological and psychiatric illnesses, including autism and mental disability.
In very premature babies, myelination can be particularly prone to damage, and the researchers said they hoped their new imaging technique would in future allow doctors to directly measure whether the treatments given to premature babies are able to help normal brain development.
Deoni's team scanned 14 healthy babies who were born at full term. They were scanned while they were asleep using a specially-modified, quiet, baby-friendly MRI scanner.
To build up a picture of their myelin development, the scientists scanned the infants monthly between 3 and 11 months and found that by 9 months, they could see that myelination had taken place in all areas of the brain.
Until now, we've not been able to show how myelination develops in babies but this new MRI technique allows us to do just that, said Declan Murphy, also from King's College London, who oversaw the research.
He said the technique could now be used to understand how differences in the way brains are wired up relate to neurological and mental disorders that may not become obvious until later in life.
The next step to scan premature babies and see how their myelin development differs from babies born full term, and how connections in the brains of babies who are at greater risk for developing autism differ from others, he said.