News The latest developments in autism research.

Brain-wave patterns may flag babies with autism

by  /  12 May 2017
Brain blip: An electrical signal known as P150 might serve as an autism biomarker in infants.

dblight / iStock

Infants who are later diagnosed with autism show inconsistent patterns of brain waves in response to the same sound. The unpublished results, presented yesterday at the 2017 International Meeting for Autism Research in San Francisco, California, suggest that this inconsistency could serve as an early biological marker for autism.

“When we think about variability, we usually cringe, because we see variability as a problem or a nuisance, something that gets in the way of what we’re actually trying to measure,” says April Levin, instructor of neurology at Boston Children’s Hospital, who presented the findings. In this case, variability distinguishes children with the condition from those without.

Levin and her colleagues used electroencephalography (EEG) to record brain activity in 3-month-old babies. The study includes 25 ‘baby sibs’ — children who have an older sibling with autism and are thus at increased risk of the condition themselves — as well as 16 babies who have no family history of autism. Of the baby sibs, 11 were diagnosed with autism by age 3.

The researchers recorded brain activity as the infants listened to a recording of a person saying the syllable ‘da’ 100 times. They focused on a brain-wave signal called P150, a spike in neural activity that reflects the brain’s first response to hearing the syllable.

The team analyzed a parameter known as the inter-trial phase coherence, a measure of the timing of the P150 response each time a child hears the syllable. Low coherence indicates variable brain responses, whereas high coherence indicates consistent responses.

Babies later diagnosed with autism have more variable brain responses than do controls or baby sibs without the condition, the researchers found.

The findings jibe with those from previous studies showing that people with autism have inconsistent brain responses to other types of stimuli — such as moving images or puffs of air on the back of the hand. “We’re seeing the same trend at 3 months of age,” Levin says.

Magical thinking:

It’s unclear how the variability of the brain response relates to the core features of autism. But consistent brain responses are critical for learning. Babies with variable brain responses to the same syllable may never learn to recognize that sound, for example.

“If there’s a lot of variability, that could correlate with the inability to see some degree of consistency in the world,” says Charles Nelson, research director at Boston Children’s Hospital’s Developmental Medicine Center and one of the lead investigators of the project.

That premise is in line with the ‘magical world’ theory, which Pawan Sinha and his colleagues at the Massachusetts Institute of Technology proposed in 2014. According to this theory, children with autism have trouble learning to recognize patterns and make predictions about what might happen next — and, as a result, experience the world as magical and surprising.

Nelson’s team aims to explore whether this variable pattern exists in babies even younger than 3 months. The team is also studying children with mutations that put them at increased risk of autism and related conditions.

Even if this feature is not specific to autism, having markers “for any child who’s on a trajectory of atypical brain development — that’s still very valuable,” says Linda Copeland, a developmental pediatrician at the Center for Autism and Related Disorders in West Sacramento, California, who was not involved in the study. For example, the variability may serve to identify children who would benefit from behavioral therapy.

For more reports from the 2017 International Meeting for Autism Research, please click here.

One response to “Brain-wave patterns may flag babies with autism”

  1. C Stargazer says:

    This is quite expected and relates to how we experience sensory and dampening of said senses. There are previous studies that overlap with this. An NT brain may become used to an obnoxious sound to the point that it no longer bothers them. Not the case for some of us depending on whether the “signal” is too strong or too weak. Friendly reminder that strong senses can be experienced as physical pain or extreme discomfort.

    It’s the reason I could watch the same exact program as a toddler over and over for hours at a time, because each time I was noticing something different and making mental notes. We’re making distinctions that NT brains do not make due to their dampening abilities. It can take longer to “connect the dots” because of this. When dealing with simple subjects, it can be a hindrance, when dealing with complex subjects it can be very useful. A skill learned in one environment may not automatically translate to another environment even if it seems obvious.

    It’s also where my early childhood echololia came from. I was noticing so many different variables that it was impossible to communicate what I was thinking, so I stuck to phrases and gestures intended to communicate more context than they possibly could. I made the mistaken assumption that everyone would realize the different possible contexts of my selected phrases and would become upset when they didn’t. Using the same words and phrases to communicate different meanings, much in the way slang does. There is also the difficulty for a young mind of only having NTs as a source of context for communicating things that NTs do not experience.

    Imagine all the ways you can break down “da”. there’s the D, there’s the “ah”. There’s the timing in it, how long each part lasts. You might pay more attention to the middle, beginning or end even though it is very short. That comes before learning the meaning and context of the “word”. You might be busy replaying it in your mind while someone is trying to talk to you. Now imagine if different people are saying the same word, they might have different voice inflections or accents as well. If I was around someone with an accent for a day, I would start using it without consciously thinking of it(after I started speaking of course).

    It’s not that we’re having trouble recognizing simple patterns, it’s that we’re taking simple concepts and breaking them into complex variables while those trying to teach us are expecting us to respond in the same way they did. It actually requires more complex pattern recognition to process it. For a young brain functioning in this way, of course it’s going to delay communication if not make it nearly impossible.

    This does not call for behavioral modification or something more “intensive”, depending on which kind of behaviorism is being followed; it calls for different teaching methods and more patience.

    It’s more important to find direct literal meanings that don’t leave room for different contextual interpretations. It’s also important to identify which senses are strong or weak, as that will have an impact on learning too. If you’re using a sense that is more likely to experience pain, that’s where you’re more likely to cause PTSD. In that case you could consider how the deaf or blind learn/communicate or something entirely new that avoids causing physical discomfort for strong senses or avoids using senses that are too weak.

Leave a Reply

Your email address will not be published. Required fields are marked *