How autism presents in small children

For the past twelve years, Terje Falck-Ytter has been studying autism in children using a variety of experiments. A diagnosis of autism can only be made when children are around two to three years old, but he has been able to show that there are differences in how they interpret their environment long before this. However, these are subtle deviations, not something anyone would be able to identify in everyday interactions.

“People might initially think that it would be easy to see which babies will go on to develop autism, but it is not. They follow the gaze of others and look at faces much like other children do. However, we have discovered a number of clear differences in the groups when examining non-social traits, such as how people react to and interpret sounds and visual impressions more generally,” explains Falck-Ytter, Professor of Psychology and leader of the Development and Neurodiversity Lab research team.

Difference in brain activity in babies

In March, Falck-Ytter published an article in collaboration with researchers at KIND (Center of Neurodevelopmental Disorders at Karolinska Institutet), showing that children who are later found to meet the criteria for autism interpret visual information differently as early as at the age of five months. The babies had to look at a screen with dots moving around chaotically and then forming different patterns. Meanwhile, they wore a cap that measured their brain activity. When the infants looked at complex patterns, the researchers could see that the brain activity was different in those who were later found to have symptoms of autism.

“The notion that we could see this difference several years before the symptoms of autism developed is completely new, and it indicates that there is a certain type of visual stimuli to which they react differently,” continues Falck-Ytter:

“Facial movements are complex, which could mean that there are also fundamental differences in how they interpret facial expressions at this age. This is something we now want to look at more closely.”

Several studies confirm differences in brain development

In previous studies, researchers have also observed differences by examining children’s eye movements and pupils. For example, they have studied how ten-month-old babies react when a light starts flashing next to a person opposite, without the person appearing to see it. Most children tried to attract the adult’s attention with their eyes, but the babies who were later diagnosed seemed less interested in this communication.

“We wanted to study how they tried to initiate interaction with the other person, which is thought to reflect their social motivation. What we could see was that they looked back and forth less compared to the children who did not go on to develop autism.” 

In another experiment, they also noted certain differences in how children were interested in background noise. 

“Children who were later found to have autism reacted more to non-social background noises. The pupils became more dilated, showing that they react to this kind of background noise, such as sounds heard in a kitchen.”

Autistic children good at seeing details

The ability to focus on details can also be a strength. When the research team asked three-year-olds diagnosed with autism to find a cross in a complex picture, they were able to locate it faster than the children without autistic traits.

Studies have also disproved their assumptions. Falck-Ytter explains how they thought children with autism would have more difficulty with motor skills as babies. However, when they studied how good babies at ten months were at catching a ball, they could not see any differences compared to the control group.

Studying siblings

Around one to two percent of the population has autism. Falck-Ytter explains that there are probably several hundred genes that can combine to lead to a diagnosis, but that each gene usually has only a small effect. It is clear that there is an obvious hereditary factor, which is why the studies have recruited families with a child who has already been diagnosed with autism. The likelihood of the next child being diagnosed is then between ten and twenty percent. There is also a gender bias, with autism more prevalent in boys.

“It is not clear why it is more common in boys than girls, but one hypothesis is that it is linked to sex hormones that affect the likelihood of autistic development differently in boys and girls.”

The studies conducted over these years are part of Project EASE (Early Autism Sweden), a collaboration between Uppsala University and KIND. The researchers followed around 300 children from five or ten months of age until the age of three. The participants came from all over Sweden and travelled with their families to both KIND and Uppsala several times to take part in the various visitor days. 

“Long-term funding is needed to carry out this type of study. It took almost ten years from when we started to when the articles began to be published,” adds Falck-Ytter.

The research team has now completed the data collection and is entering an analysis phase, during which they will also compare their results with European partners.

Eliminating autism not the goal

Although the project has been extremely resource-intensive, Falck-Ytter sees major benefits in studying young children. Trying to define autism in adults is a challenge because, after living with the symptoms for many years, people may have characteristics that should be seen as the consequences of autism rather than 'autism itself'.

“It is easier to understand what lies at the core of autism by examining infants and children before all these layers of complexity arise.”

Knowing more about how autistic children perceive and interact with their environment will help to adapt the environment and provide individualised support.

“The goal is not to eliminate autism, as it reflects general differences in the population linked to both strengths and weaknesses, rather it is about finding ways to support children. We want to help stimulate development so that the person can communicate and participate in society in the future in the way he or she wants.”