Extra brain cells may be key to autism

2011-11-09 10:08

kalahari.com

Chicago - Children with autism appear to have too many cells in a key area of the brain needed for communication and emotional development, helping to explain why young children with autism often develop brains that are larger than normal, US researchers said on Tuesday.

Their study suggests the condition starts in the womb because brain cells in this area known as the prefrontal cortex typically develop during the second trimester of pregnancy.

The findings could help narrow the search for a cause of autism, which affects one in every 150 children born today in the US, or about 1% of the population.

"We found a really remarkable 67% increase in the total number of brain cells in the prefrontal cortex," said Dr Eric Courchesne of the University of California San Diego Autism Centre of Excellence, whose study appears in the Journal of the American Medical Association.

Courchesne and colleagues carefully counted the number of brain cells in tissue from seven boys with autism who had died and six boys who did not have autism at the time of their deaths.

Brain overgrowth

They focused on the prefrontal cortex, a part of the brain which is thought to grow too large and too fast in children with autism.

"It's a part of the brain that's important for social, emotional and communication functions, and it composes about 25% to 30% of the cerebral cortex," Courchesne said in a telephone interview.

His team was first in 2003 to link rapid growth in head circumference in the first year of birth with autism.

He said the finding of excess brain cells in the prefrontal cortex explains brain overgrowth in autism, and hints at why brain function in this area is disrupted.

"This isn't just a simple increase in neurons. It means a huge increase in potential connections and, therefore, a potential for mis-wiring which would lead to abnormal function," Courchesne said.

Autism is a spectrum of disorders ranging from a profound inability to communicate and mental retardation to relatively mild symptoms such as with Asperger's syndrome.

Scientists have found dozens of genes that may raise the risk of autism. But genetic causes only explain 10% to 20% of cases, and recent studies have pointed to environmental factors, possibly in the womb, as a potential trigger.

'Something solid'

"For years, it's been a big puzzle from the standpoint of evidence. Where is the evidence that autism has a prenatal origin?" Courchesne said.

"For the first time, we have something really solid," he said.

The team found excess brain cells in each child with autism they studied, Courchesne said. And the brains of the autistic children also weighed more than those of typically developing children of the same age.

Lizabeth Romanski of the University of Rochester Medical Centre said the findings show that the origins of autism occur very early.

"The generation of new neurons, what we call proliferation, occurs prenatally during the second trimester," said Romanski, who was not involved in the study. "That is when these neurons are being born."

She said the finding of a large number of these neurons in children with autism suggests something occurred during this period to change the way the brain develops.

The researchers acknowledge that their study is small.

Courchesne said it is difficult to find brain samples from young people with autism, and his study included some from very young children, ranging from ages 2 to 16.

"This really says prenatal life is a very important time to study and mechanisms there will eventually lead to our understanding of how autism comes about," he said.

Read more on:    health  |  research
NEXT ON NEWS24X

Read News24’s Comments Policy

24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
1 comment
Add your comment
Comment 0 characters remaining
 

Inside News24

 
 

Zuma: Pray for peaceful polls

President Jacob Zuma has asked members of the Universal Church of the Kingdom of God to pray for peaceful elections on 7 May.

 
 

Latest elections multimedia

Why Jack Parow wants you to vote on 7 May
The ad the SABC doesn't want to air
Elections 2014 in one cartoon
This year's election posters
 
Traffic
Lottery
 
  • Friday Grabouw - 11:32 AM
    Road name: N2 Eastbound
    DELAYS between Sir Lowrys Pass and Grabouw
  • Friday Cape Town - 10:14 AM
    Road name: M3 Inbound
    EVENT - left lane closed between Rhodes Avenue and UCT
 
More traffic reports...
 

Jobs in Cape Town [change area]

Property [change area]

Travel - Look, Book, Go!

Escape winter, head to Mauritius

Escape winter by spending 7 nights in Mauritius' tropical bliss from R13 215 per person sharing. Includes return flights, airport transfers and accommodation. Book now!

Kalahari.com - shop online today

Get many eggs in one basket!

Gaming bundles: 2 Super Hits games for R99, 3 Disney games for R99 and more + exclusive accessory bundles only available on kalahari.com. While stocks last. Shop now!

25% off bestselling books!

The Real Meal Revolution by Tim Noakes, Jeffrey Archer’s Be Careful What You Wish for, Man’s Search for Meaning by Victor E. Frank and many more titles. Shop now!

Up to 25% off electronics

Buy top electronics and save up to 25%. Such as kalahari.com’s 1# selling product the gobii eReader, Patriot X Porter flash drive, Asus Nexus 7” 3G tablet, Samsung Galaxy SIII, Lenovo G580 Notebook and many more. Shop now!

DStv HD PVR Decoder now R949

The DStv HD PVR Decoder has further revolutionised the television experience with lifelike viewing, sharper images, more vibrant colours and precision picture quality. Now R949, save R550. Offer valid while stocks last. Shop now!

Up to 30% off appliances & homeware

Save up to 30% on appliances and homeware this Easter! Offer valid while stocks last. Shop now.

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

BlackBerry Bold 9790

Bold Design The BlackBerry Bold 9790 smartphone combines the iconic BlackBerry...

From R2979.00

I'm shopping for:

Horoscopes
Aquarius
Aquarius

Self-indulgence may be strong today. You may want to enjoy yourself to the fullest and share it with those that make you feel...read more

There are new stories on the homepage. Click here to see them.
 
English
Afrikaans
isiZulu

Hello 

Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.


Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.

Settings

Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.








Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.