An analysis of how nerve fibers make vital connections during brain development could aid the understanding of how some cognitive disorders occur.
University of Queensland scientists at the Queensland Brain Institute, the School of Mathematics and Physics, and the School of Biomedical Sciences identified six key dimensions of the shapes that the tips of nerve fibers take on while navigating through the developing nervous system to make a connection.
Study leader Professor Geoff Goodhill from QBI said the relation between these shape dimensions and nerve fiber growth had been poorly understood.
“We’re trying to understand how nerve fibers are guided to their target,” Professor Goodhill said.
“The tips of nerve fibers have very complex shapes, but there previously hasn’t been much research into understanding them.
“There are believed to be an astonishing quadrillion nerve connections in the brain, and by understanding what’s involved in normal nerve fiber guidance, we can start to see what we can possibly do to prevent miswiring from occurring.”
Recent discoveries suggest that wiring problems may underpin a number of nervous system disorders including autism, dyslexia, Down syndrome, Tourette’s syndrome and Parkinson’s disease.
“Many cognitive disorders have been linked to the initial wiring of the brain during development, so by understanding the basic rules by which nerves find their targets, perhaps we could ultimately help prevent these disorders in the future,” Professor Goodhill said.
“Interestingly, rat nerve fibers growing in a culture dish, and zebrafish nerve fibers in the living brain, displayed the same growth cone shapes.
“That is good evidence to indicate that we have identified very basic biological properties that are transferrable across species.”
More than 50,000 images of nerve fibers were used in the study, using a mathematical analysis to assign 500 parameter points for the tip of each fiber to determine its shape.
A key finding of the study was that the tips of nerve fibers oscillate during navigation, and the stronger and more rapid the oscillations the faster the nerve fibers moved.
“Our next step is to study the role these shape dynamics play in nerve fiber navigation, and whether there are any behaviors we can influence,” he said.
The new analysis, published in the journal BMC Biology, was funded by grants from the Australian Research Council and National Health and Medical Research Council.
Contact: Darius Koreis – University of Queensland
Source: University of Queensland press release
Image Source: The image is credited to Zac Pujic and is adapted from the University of Queensland press release
Original Research: Abstract for “The dynamics of growth cone morphology” by Geoffrey J Goodhill, Richard A Faville, Daniel J Sutherland, Brendan A Bicknell, Andrew W Thompson, Zac Pujic, Biao Sun, Elizabeth M Kita and Ethan K Scott in BMC Biology. Published online February 11 2015 doi:10.1186/s12915-015-0115-7