Brain Scans Detect Autism In Six Month Olds

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A brain scan of a 6-month old with autism showing abnormal neuron pathways (red and yellow).

Autism is normally diagnosed in children at around 18 months to 2 years of age, when parents see odd behavior and take their child to the doctor. Unfortunately, by the time outward symptoms are apparent much of the faulty brain architecture underlying autism has already taken form. Corrective therapies that last a lifetime are all too often powerless to reverse the damage that occurred in those first two years. But a new study offers hope that autism could be detected in children as young as 6 months old and give treatments that much more of a head start.

Researchers at University of North Carolina’s Institute for Developmental Disabilities imaged the brains of 92 children who were at high risk for autism. Scans were performed when the children were 6 months, 1-year, and 2-years old. At 2 years, the age when children are typically diagnosed, 30 percent of the children were found to have autism. The researchers then compared the brain images of the autistic children with the others. They saw differences in the brain’s white matter, the axon-laden pathways that transmit electrical signals to distant parts of the brain. Of the 15 pathways analyzed, 12 were significantly different between autistic and non-autistic children.

Autism remains a poorly understood disorder even after a century since it was first diagnosed.

Other researchers have performed an analogous experiment in which they monitored the growing infants’ behaviors in an attempt to identify tell-tale behavioral abnormalities, but as far as the UNC researchers are aware, they are the first to uncover brain imaging differences at such an early age. The study, which was published recently in the American Journal of Psychiatry, extends other brain imaging research that has shown that toddlers 2- and 3-years old have larger than normal brains and post-mortem measurements that show autistic adults have larger brains as well.

Autism is a complex disorder the biological cause of which continues to elude scientists. It’s main symptoms include impaired social interaction and restricted and repetitive body movements. We know it has a genetic component because two identical twins are more likely to share the disease than two fraternal twins. Although autism affects one in 110 children on average, children born into families with a history of autism have an almost one in five chance of being autistic. The children in the current study were considered high risk because they had older siblings who’d already been diagnosed with the disorder.

Treating autism, understandably, is a work in progress. Behavioral strategies such as placing the child in visually stimulating surroundings, speech-language therapy, physical therapy, medications and other therapies are used but no silver bullet has been found as yet. What is well established, however, is that beginning treatment early and intensively greatly improves the child’s chances of making progress. The promise of the current study is the possibility of beginning therapy long before outward behavioral symptoms begin to manifest themselves.

Not all are as hopeful. An issue being raised by some is the subject-to-subject variability in the study’s brain images. They question whether or not the differences in white matter between autistic and normal children will be robust enough in future diagnoses to overcome that variability. The study’s lead author, postdoctoral fellow Jason J. Wolff, acknowledged that the study is “preliminary” in a UNC news report. He also called it a “great first step” in uncovering a new indicator that could be used to diagnose even younger children.

Whether or not differences in white matter tracts will prove a useful to future diagnoses, it stands on its own as a discovery of the autistic brain. If clinicians don’t find the study useful, researchers surely will.

[image credits: UNC, Topnews]
image 1: brain scan
image 2: autism

Discussion — 14 Responses

  • arpad February 24, 2012 on 7:37 am

    It’s good that there’s a cautious tone to the article. Autism is still diagnosed by observation with a good deal of ambiguity as part of every diagnosis. The problem is that the underlying mechanism of autism isn’t understood so it’s only the “ripples” of the condition that can be observed and not the “pebble” that causes them.

    Puts me in mind of an article I read about how genetic science advances had resulted in an explanation for why some breast cancer was responsive to chemotherapy and progressed relatively slowly and other breast cancer was inherently resistant to treatment and much more aggressive.

    Turns out they were two, genetically distinct forms of cancer that had a similar diagnostic presentation – as breast cancer. Treatment developed for the majority of cases, the less invasive variety, would only have impacted the other variety by accident. It didn’t but now researchers understand why. So treatments can be developed to combat the other variety of breast cancer.

    My point? Autism is a bag of symptoms. We don’t have any idea whether we’re dealing with a single, underlying cause that presents differently due to subtle differences in brain chemistry or several distinct conditions that have a degree of overlap in symptomology.

    The reason why that distinction’s important is embodied in the lesson of the different types of breast cancer. The brain scan that purports to detect autism is only verified by the development of autism-spectrum symptoms which means that the observation of one symptom, the development of autism-spectrum behaviors, is used to verify another symptom, the results of the scan.

    From a treatment perspective though this development could be very important although that remains to be seen. Beginning ameliorative treament as early as possible seems to help some autism patients and, as always, knowing more is better then knowing less.

    • turtles_allthewaydown arpad March 15, 2012 on 2:15 pm

      It’s things like this that make me question the inevitability of total singularity. There’s a lot to the body yet, and we don’t even know the questions we should ask in many cases, let alone what the answers are or what to do once we get the answers.

      In the face of that, the singularity, trans-human folks make me think back to the Titanic. One hundred years ago, we had recently tamed electricity and developed electric lights to overcome the darkness, we had developed the wireless telegraph, railroads, germ theory. Science was tackling every obstacle nature had in our way, and if engineers had built an unsinkable ship, then there was no need for lifeboats, it was lucky they put any on it.

      I think our imagination and hubris is getting in our way here, and the future isn’t going to unfold nearly as quickly as some people think. There’s a lot to our body that we aren’t even close to understanding.

      • PRiME turtles_allthewaydown March 31, 2012 on 2:25 am

        I think science and technology is unfolding at a rate that which our society is unable to handle in its current structure.

        We are heading towards a cross-roads in other words where people may segregate from those who want to move forward in thinking with technology ‘that is changing the way we see ourselves in the universe’ and those that wish to hold onto old pretentious ideas. (Its obvious which I choose from my tone)

        Some of those old ideas have very good moral grounds, but chaotic as us humans are, we are unlikely to choose wisely.

        Basically our backward thinking in society WILL and IS holding us back, so progress is going to be slow, for now.

  • Lisa Woods November 29, 2012 on 7:38 am

    I think this is an excellent approach that could be complemented with biochemical measurements. For example, we are working on a project examining mass spectrometry analysis of autism biomaterials:

    http://www.rockethub.com/projects/11806-autism-and-protein-markers