As a researcher, one thing I have always been fascinated with, is how the autistic brain differs from the neurotypical brain. How specific environmental stimuli in the brain of an autistic child compares to the response occurring in a neurotypically-developing child. Last week, I had the wonderful opportunity to meet with Dr. Geraldine Dawson, the William Cleland Distinguished Professor of Psychiatry and Behavioral Sciences at Duke University. She is the director of the Duke Center for Autism and Brain Development, a research clinic whose goal is to improve the quality of lives of individuals with autism through research and other services. She has published over 300 scholarly articles and 12 books on autism and brain development. We talked about new techniques in autism screening, early intervention strategies and some of the research she is conducting.
The Real Spectrum: How did you get involved in autism research?
Dr. Geraldine Dawson: My first experience with autism was as a high school student. I was a babysitter for this family who had two twins with autism and who lived across the street. Unfortunately, the father was very ill and had to travel often to receive medical treatment. So, I took care of the kids in the family, including six-year-old autistic twins. I very much enjoyed being with them and learning all about their unique ways of being in the world, their idiosyncrasies, and the things that they enjoyed – we spent a lot of time playing pool together. I definitely felt really drawn to wanting to understand more and to get more involved with people that were neurodevelopmentally disabled. Then, in graduate school, I was being trained as a clinician, a clinical psychologist, and a developmental psychologist. My first case clinically was a young child who was diagnosed with autism. At that point, we knew very little about the causes of autism and we knew very little about the treatments and therapies to help the child and their family. I am very interested from a scientific point of view to understand what are the reasons for their differences, the way that the brain works, and how we can develop therapies and support systems that will help the child fulfill his or her potential. I decided to devote my career to autism.
What are the goals of your intervention strategy, the Early Start Denver Model?
There are several basic principles of Early Start Denver Model, or ESDM. First of all, it’s based on developmental science and what we know about how infants and children learn. As you may be aware, when you think about a baby or a young child learning, they learn through interaction with other people and also mainly through play. It would be very unusual to sit down with a baby and teach them to make eye contact or even how to play with an object. What happens is that we have these very natural interactions with infants and toddlers and through that interaction, they learn about the world. We wanted the teaching to occur in natural play based interactions. The second thing is to have the interaction be very enjoyable and motivating for the child to give them more of an opportunity to make choices and initiate what they were interested in doing. Some of the previous interventions have been very structured, very didactic, and wouldn’t allow the child to choose what they were interested in. The reason that it is so important is because people learn about things that they care about and when they are emotionally engaged in an activity that they find activity, they are more likely to pay attention. We are interested in following the child’s lead and embed teaching into those activities they prefer.
You have found that in infants with ASD, they undergo aberrant development of white matter pathways indicated by higher fractional anisotropy values. What do you think is the underlying mechanism for this and how does this connect to characteristics of ASD?
That’s more of the work that is being led by Joe Piven, a psychologist at University of North Carolina Chapel Hill. I was a part of their initial work but they have continued to do that work which has been phenomenal. When we think about how it would be at this early age – between 6 and 12 months – that the brain is developing differently, we believe that it is most likely genetic factors. In particular, in the studies that Joe Piven has led, where they have been following infants perspectively in doing brain imaging, these are infants who have an older sibling with autism. If there is one child in a family with autism, the next child to be born has a higher risk of developing autism. So overall, I think this phenomenon of aberrant development of white matter pathways is simply due to genetic factors and heritable neurological characteristics.
I haven’t seen many studies on hemispheric asymmetry. You did a study on hemispheric specialization and how it relates to the language skills of children with ASD. You found that the majority of autistic participants found reversed patterns of this asymmetry where the right hemisphere is more dominant in language abilities. What could be the mechanism for this but also what led you to research this aspect of the disorder?
That finding of differences in how the brain is specialized in autistic individuals, that is really held up over the years and has been studied in a lot of different ways. For example, Eric Krushein at UC San Diego did a study where he studied 2-year-old toddlers who were on the spectrum while they slept in an MRI machine. They told the toddlers bedtime stories and with a neurotypical toddler, you’d see the left hemisphere lighting up while listening whereas in autistic toddlers, the pattern was different and didn’t show this strong left hemisphere specialization. One theory is that the brain actually becomes specialized through experience with information in the world. So, a good example would be that when babies are born, they can perceive all of the phonemic units of all of the languages in the world. Of course, the babies are then later only exposed to certain languages. It turns out that individual languages only have certain phonemic contrasts. Over the first year of your life, the brain is listening and responding to this information which stimulates neural circuits that get retained. The synapses not utilized end up dying away. When you think about an autistic infant or toddler, they are not paying as much attention to the world of language nor faces whereas they’re paying much more attention to objects around them and music. They’re changing the way that their brain is organized and studies have shown that the autistic brain is highly specialized in the areas that autistic individuals excel in, but for language, since they don’t pay much attention to it during the early years, it likely changed the way in which it was organized. In another study, we used EEG to look at how the brains of autistic preschoolers were responding to social information. Some of the kids were provided with an early intervention, whether they were much more engaged with people, and other toddlers were not provided with the intervention. You could really see the changes in brain activity and were the result of different experiences they had. It could also be due to genetic factors driving that but it is mainly due to attention patterns and how that affects how their brain is wired.
What is some of the current research going on at the Duke Center for Autism and Brain Development?
We do a wide range of studies. We have been very interested in developing better ways for screening for autism. Currently, the way we screen is to give a parent or caregiver a questionnaire where they are asked about certain behaviors and if their child shares these behaviors. This is done usually in primary care by a pediatrician and we are very happy that this questionnaire is used – it helps a lot. We also know there are definitely limitations to a questionnaire. Oftentimes there may be language barriers. So, you would have to have the questionnaire in all different languages or use an interpreter which may cause some issues. Additionally, different cultures interpret the questions differently or the parents may not have a good understanding of child development. We are interested in developing new technologies where we can directly observe the child’s behavior and measure differences that may indicate that the child may have an autism diagnosis. We have actually developed an app that has a set of brief movies that are shown on an iPhone or an iPad. The child watches these movies that are designed to elicit different behaviors, such as smiling or looking at certain things. The camera in the device records the child’s responses to the movies and then the videos are uploaded and analyzed automatically by using computer vision analysis, measuring behaviors and vocalizations. We can really detect early signs of autism and have implemented it in Duke primary care. More recently, we received funding to administer an infant version of the app – to start at 6 months of age – and see if we could pick up on early signs of autism before you could even make a diagnosis.
What advice would you have for young females, wanting to start a career in STEM fields?
My advice is to follow your passion. Be a good observer. It is those direct observations that will help you come up with new ideas. Take risks with those new ideas. Have faith in them. Understand that some of those ideas may not pan out but you have to have faith in that creative process and your own thoughts. Don’t be reticent to test and evaluate them.