Australian scientists are studying the brain to gain new insights
into "wiring defects" suspected of causing Parkinson's disease, autism
and other disorders.
Professor Geoffrey Goodhill says the brain's wiring -
billions of tiny nerve fibres known as axons - are steered into position
by a gene-based signal and this process could go awry.
"During the brain's development, billions of nerve cells
send out nerve fibres which have to find the appropriate target to form
the right connection," said Prof Goodhill of the Queensland Brain
Institute, based at the University of Queensland.
"If there are problems with some of genes coding for the
proteins which set off these guidance cues, sometimes they can head off
in the wrong direction."
Earlier research has shown how these axons could turn
left or right in response to a strong signal, but questions remained as
to what occurred when the signal was weak.
Prof Goodhill's research has shown how the axons could
slow down their rate of growth in response to a weak signal and then
speed up again when they confirmed they were on the right path.
"We're continually generating new neurons throughout our
life and they have to make connections with other neurons ... they send
out axons and they have to all, somehow, get wired up in the right way,"
he said.
"What we're suggesting in addition to turning, under some
circumstances, there is another speeding up or slowing down-type
mechanism.
"Speeding up or slowing down is a way that can help them
get to where they are going."
Prof Goodhill said the research had uncovered "another
piece of the puzzle" of how the brain was built and a new avenue for
research into causes of cognitive disorders.
There was increasing evidence that the same genes which
control the brain's wiring process were also implicated in disorders
including autism and Parkinson's disease, he said.
"Wiring defects seem to underlie a lot of cognitive
disorders, and therefore we need to understand what the basic rules
are," Prof Goodhill said.
"This new discovery is helping us to do that."
The research is to be published by the journal
Proceedings of the National Academy of Sciences.
Source: Sydney Morning Herald - http://tinyurl.com/yf6l558