Social Media Sidebar

Announcement

Please sign up, comment on articles and bring your friends!

Current poll

PlanetTech is asking:

What do you think about our new web site?

Love it, indeed
Really good solution
Same as old one
The old one was better
This is a new option

Quote of the day

When seen through the lens of technology, few resources are truly scarce; they’re mainly inaccessible. 

 

Peter Diamandis

Study finds altered brain chemistry in people with autism

RATE THIS! +50
Posted in Science on 18th Dec, 2015 05:02 PM by AlexMuller

Neuroscientists have found a link between a behavioral symptom of autism and reduced activity of a neurotransmitter whose job is to dampen neuron excitation. The findings suggest that drugs that boost the action of theneurotransmitter GABA, may improve some of the symptoms of autism, researchers say.

 

Brain activity is controlled by a constant interplay of inhibition and excitation, which is mediated by different neurotransmitters. GABA is one of the most important inhibitory neurotransmitters, and studies of animals with autism-like symptoms have found reduced GABA activity in the brain. However, until now, there has been no direct evidence for such a link in humans.
 
“This is the first connection in humans between a neurotransmitter in the brain and an autistic behavioral symptom,” says Caroline Robertson, a postdoc at MIT’s McGovern Institute for Brain Research and a junior fellow of the Harvard Society of Fellows. “It’s possible that increasing GABA would help to ameliorate some of the symptoms of autism, but more work needs to be done.”
 
Many symptoms of autism arise from hypersensitivity to sensory input. For example, children with autism are often very sensitive to things that wouldn’t bother other children as much, such as someone talking elsewhere in the room, or a scratchy sweater. Scientists have speculated that reduced brain inhibition might underlie this hypersensitivity by making it harder to tune out distracting sensations.
 
In this study, the researchers explored a visual task known as binocular rivalry, which requires brain inhibition and has been shown to be more difficult for people with autism. During the task, researchers show each participant two different images, one to each eye. To see the images, the brain must switch back and forth between input from the right and left eyes.
 
For the participant, it looks as though the two images are fading in and out, as input from each eye takes its turn inhibiting the input coming in from the other eye.
 
“Everybody has a different rate at which the brain naturally oscillates between these two images, and that rate is thought to map onto the strength of the inhibitory circuitry between these two populations of cells,” Robertson says.
 
She found that nonautistic adults switched back and forth between the images nine times per minute, on average, and one of the images fully suppressed the other about 70 percent of the time. However, autistic adults switched back and forth only half as often as nonautistic subjects, and one of the images fully suppressed the other only about 50 percent of the time.
 
Performance on this task was also linked to patients’ scores on a clinical evaluation of communication and social interaction used to diagnose autism: Worse symptoms correlated with weaker inhibition during the visual task.
 
The researchers then measured GABA activity using a technique known as magnetic resonance spectroscopy, as autistic and typical subjects performed the binocular rivalry task. In nonautistic participants, higher levels of GABA correlated with a better ability to suppress the nondominant image.
 
But in autistic subjects, there was no relationship between performance and GABA levels. This suggests that GABA is present in the brain but is not performing its usual function in autistic individuals, Robertson says.
 
“GABA is not reduced in the autistic brain, but the action of this inhibitory pathway is reduced,” she says. “The next step is figuring out which part of the pathway is disrupted.”
 
“This is a really great piece of work,” says Richard Edden, an associate professor of radiology at the Johns Hopkins University School of Medicine. “The role of inhibitory dysfunction in autism is strongly debated, with different camps arguing for elevated and reduced inhibition. This kind of study, which seeks to relate measures of inhibition directly to quantitative measures of function, is what we really to need to tease things out.”

Tags: brainautismneuroscienceneuronsmedicineresearchpsychology

Read original article » Back to category

Comments

Author: Guest
Posted: 2015-12-19
+1
I agree, this is really great piece of work. The findings that GABA is not working and there is no suppression support many previous behavioural observation. The big question is why Reply
Author: Guest
Posted: 2015-12-19
+0
Autism is a spectrum of diseases and more has to be done to analyse people across this spectrum. It would be important to find is deregulation of GABA pathway a common molecular feature Reply


 

Recent headlines

  • Posted in Medicine on 2017-11-21 09:01:15
    High Incidence of PTSD Among Cancer Patients..read more
    Posted in Science on 2017-11-21 08:56:02
    Human Memory Enhanced With a Brain Implant For the First.....read more
    Posted in Hardware on 2017-11-21 08:51:13
    MIT Reveals a Battery That Stores Solar Energy to Make.....read more
    Posted in Science on 2017-11-21 08:45:29
    Japan discovers new 50km cave in moon, raises hope for.....read more
    Posted in Software on 2017-11-20 17:24:02
    The 3 biggest threats to your Bitcoin (and 10 tips to.....read more
Posted in Business on 2013-10-10 01:33
China is working towards a manned lunar mission in about.....read more
Posted in Business on 2013-10-20 07:17
Spacex says China is their main competitor for commercial.....read more
Posted in Software on 2013-10-20 06:43
Pirate Bay Browser Clocks 1,000,000 Downloads..read more
Posted in Medicine on 2013-10-10 02:10
Google reportedly investing hundreds of millions into new.....read more
Posted in Medicine on 2013-10-14 03:13
Endothelial Cells Can Repair and Regenerate Organs,.....read more
Posted in Science on 01.01.2010
Spacex says China is their main competitor for commercial.....read more
Posted in Science on 01.01.2010
Staring at Your Phone Could Be Making You Short Sighted..read more
Posted in Science on 01.01.2010
Oculus Rift virtual reality headset coming to mobile, but.....read more
Posted in Science on 01.01.2010
China is working towards a manned lunar mission in about.....read more
Posted in Science on 01.01.2010
Delivering drugs via nanoparticles to target mitochondria..read more

Recent Blog Posts

  • Posted by AlexMuller
    Martian landscapes formed from sand 'levitating' on a little.....read more
    Posted by AlexMuller
    Scientists detect comets outside our solar system..read more
    Posted by AlexMuller
    Advanced artificial limbs mapped in the brain..read more
    Posted by AlexMuller
    Bacteria have a sense of touch..read more
    Posted by AlexMuller
    Recurrent brain cancer: New hope with phase 1 clinical trial.....read more

Login to your Account

Login to your PlanetTech Account here

Username:
Password:
Remember me
or

Create a New Account

You just need username and password

The following errors occured:
Username:
Email:
Password:
Verify password:
Remember me