Understanding the Autism Brain (for teachers & parents)
You might already be aware that people with autism experience the world differently. This has a lot to do with how their brains are wired.
In this blog post, we’ll explore what makes the autistic brain function differently from the neurotypical brain, and what this means for kids, teens, and adults who are disabled by autism.
Is autism a brain disorder?
Differences in the brains of people with Autism Spectrum Disorder (ASD) affect communication, interaction, and motor development.
Brain differences associated with autism vary from person to person. As a result, the exact cause of autism is not yet understood. It may be that there are different causes in different people.
Studies have shown that kids with autism are more likely than other kids to have neurological disorders such as epilepsy, macrocephaly (an abnormally large head), hydrocephalus (a build-up of fluid in the cavities of the brain), cerebral palsy, headaches, migraines, and congenital abnormalities of the nervous system. Many people who have autism also have other comorbid conditions such as ADHD, dyspraxia, allergies, sleep disorders, and gut disorders. A new study using PET scans has revealed that autistic individuals have fewer brain synapses, and a lower synapse counts correlated with more pronounced autistic traits.
How does autism affect the brain?
Autism affects the brain in various ways, some of which researchers don’t yet fully understand. For example, there are several different theories of over or underconnectivity between certain parts of it. But before we get into any scientific theory, let’s first look at how autism affects the brain on a practical level.
Stimming
Stimming occurs because the brain requires the body to give it predictable, repetitive sensory feedback. An example of one common type of stimming is vocal stimming. Check out my blog post on vocal stimming to find out more.
Sensory processing differences
The autistic brain processes sensory input (or stimuli) in such a way that it is difficult for many individuals to tune out the minor sounds, noises, smells, and sensations that other people can easily get used to.
Imagine a school setting, for example. In neurotypical kids, unimportant sounds such as the air conditioner or the sound of pencils on paper will initially trigger brain activity as they process the noise. After a short time, the brain will react less to these stimuli, allowing it to focus on processing new sensory input. However, in a child with autism, the brain might not get used to these stimuli; instead continuing to process them at the same time as taking in new information. This can lead to the brain becoming overwhelmed with too many sounds, smells, and sensations to process all at once, causing sensory overload.
During sensory overload, the brain tells the body that it is in danger. This causes a person to respond as if they are being attacked, by fleeing, freezing, or fighting. When this happens, an overloaded person with autism might leave somewhere without warning, become very withdrawn, or experience a meltdown/autonomic storm.
In order to reduce the sensory input it receives and avoid becoming overloaded, the autistic brain sometimes shuts down one or more senses. When this happens, an individual might retreat into a pattern of repetitive behaviors. To anyone watching, it can seem like the child is under responsive to sensory input when their brain is actually overwhelmed. Dr. Temple Grandin (who herself has autism) writes:
“My hearing is like having a sound amplifier set on maximum loudness. My ears are like a microphone that picks up and amplifies sound. I have two choices: 1) turn my ears on and get deluged with sound or 2) shut my ears off… I discovered that I could shut out painful sounds by engaging in rhythmic stereotypical autistic behavior.”
A more stressed brain can cause more distressed and aggressive behaviors. Reducing sensory stress on the brain will help an individual with autism to have a more relaxed brain, which will in turn make them more able to pay attention to and interact with others.
How do people with autism think?
As people with autism are all individuals, they all think differently. However, people with autism are generally more likely to be logical and literal.
They may also:
find it difficult to see things from another person’s perspective.
Replay thoughts, ideas, and conversations over and over in their head.
Remember lots of details about something but find it hard to filter out what’s not important.
What does an autistic person see?
Autism can affect how an individual experiences and reacts to visual input. Some people with autism are sensitive to bright lights, busy patterns, and strong sunlight. Others, however, seek additional visual stimuli and may, for example, like to keep lights on all the time.
Understanding what visual inputs they can cope with and what ones they find overwhelming can help individuals with autism avoid their triggers and therefore help them to feel less anxious. Resources like my Create Your Own Visual Support Cut and Paste Activity can be really useful for helping many kids, teens, and young adults become more aware of, and communicate to other people, what their visual triggers are.
Additionally, there is some evidence to suggest that there may be a link between autism and vision problems. Autism appears to be more common in children with visual impairments than in the general population, and visual impairments appear to be more common in children with autism than in the general population. The reasons for this possible link are not yet clear, but some researchers think that vision problems in children with autism may stem from differences in the brain rather than in the eyes.
How does an autistic person hear?
Many children with autism have hypersensitive hearing, meaning that they are extremely sensitive to volume and/or certain frequencies. In these individuals, everyday noises that don’t particularly bother most people — such as a phone ringing or the noise of a hair dryer— can be frightening, distressing, and painful. Check out this blog post for some strategies you can try to help your child/student cope with noise.
An individual may be able to cope with some noises but not others. For example, they might enjoy listening to loud rock music but be distressed by the unpredictable and high-pitched sound of a baby crying. Some people with autism will vocal stim to block out noises that they dislike.
Many people with autism have difficulty processing and organizing sounds and noticing a change in tone of voice.
How do kids with autism learn?
Every individual with autism is different, and so each will learn in their own way. The widely held assumption that everyone with autism is a visual learner is not accurate. Some individuals prefer hands-on learning (learning by doing), while other individuals learn best by listening or reading.
Similarly, it is important to remember that not all kids with autism learn at the same pace. Some kids will learn quickly, while others may need more time.
Here are a few other things to keep in mind when teaching kids or young people with autism:
Use their individual strengths and interests
Use clear directions
Many learners with autism will be distracted by too much stimuli, such as busy pages in workbooks. (This is why I create activities and worksheets with low-distraction pages. Click here to shop my pdf download printable teaching resources.
Other resources to check out
What part of the brain does autism affect?
Hippocampus
The hippocampus is a part of the brain that plays an important role in memory and spatial reasoning. Recent research suggests that it is also involved in social interaction. Studies have found structural differences in the hippocampus in the brains of individuals who have autism. In particular, in some children with autism, the right hippocampus has been found to be unusually large.
Cerebellum
The cerebellum is a part of the brain that helps control motor coordination, something many people with autism have difficulties with. The cerebellum is also important to cognition and social skills. There is research to suggest that differences in the cerebellum play a significant role in autism.
Amygdala
The amygdala is a part of the brain that houses many emotional functions and is important to social behaviors. Research has shown that kids with autism often have an unusually large amygdala. In adults with autism, however, the amygdala can be smaller than normal. This is because in the brains of people with autism, the amygdala grows unusually quickly in early childhood but then slows down, and can even become smaller in size, after the age of 12. Research has also shown differences in amygdala activity in people with autism, as well as differences in how it is connected to other parts of the brain.
Brain’s visual areas
In a study by University of North Carolina School of Medicine, differences in the visual processing areas of the brain in infants diagnosed with autism at two years old were found to be visible at just six months of age. These differences may affect how infants with autism visually perceive their surroundings and therefore the way in which they interact with people and the environment. This could then impact on brain development.
In the study, brain scans of kids who developed autism and also had older siblings with severe autism showed that the cerebrum (a part of the brain which is in charge of speech, thought, emotions, among other important functions) was larger. The scans also showed greater surface area in the section of the visual cortex that plays a key role in object recognition, and less mature connections in the splenium, which joins the left and right visual cortices of the brain and contributes to visual attention.
Can you see autism on a brain scan?
At present, autism isn’t measured by a medical test, it’s assessed by observation of behaviors. However, magnetic resonance imaging (MRI) brain scans used in numerous studies have shown structural differences in the brains of people with autism. In the future, it may be the case that biomarkers such as rapid brain growth could be used to detect autism in children before behavioral signs are noticed, potentially allowing for early intervention.
According to research presented by neurologist Dr. Evdokia Anagnostou at the International Society for Autism Research 2022 annual meeting, brain differences in individuals diagnosed with conditions such as Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD), Obsessive Compulsive Disorder (OCD), and intellectual disability don’t necessarily match up with what they are diagnosed with. Importantly, neuroimaging shows that in kids with mild autism, the brain looks almost exactly the same as in kids with ADHD or OCD, but different to how it looks in kids with severe autism. This means that, based on the current diagnostic framework, two kids could both have the same diagnosis of autism yet their brains are actually structurally different.
Autism brain vs normal/neurotypical brain
As we have seen, the autistic brain is in many ways different to the normal/neurotypical brain.
For some time, it was thought that the mirror neuron system in people with autism might not function correctly, and that this could be a significant basis for why many individuals with autism find it difficult to read people. But work by Ilan Dinstein, a neuroscientist at the Weizmann Institute in Israel, appears to contradict this popular theory. A study carried out by Dinstein and his team suggests that the mirror neuron system functions normally in people with autism. However, the study looked at only 13 individuals with autism and 10 without. For this reason, it has been argued that the study was too small to draw reliable conclusions from. Moreover, Mirella Dapretto, a neuroscientist at the University of California, Los Angeles, says that even if the findings are accurate, it is still possible that mirror neurons function abnormally in the autism brain. It may be that the mirror neuron system is more dysfunctional the more profound an individual's autism is.
Autism brain differences
Autism brain connectivity
Autism may be characterized by underconnectivity between some regions of the brain, and overconnectivity between others. However, the findings of research into functional connectivity in the autistic brain have been inconsistent.
Autism brain size
One common characteristic in kids with autism is an unusually large head. According to Spectrum News, unpublished research presented at the 2022 International Society for Autism Research annual meeting points to why this might be. Researchers from the University of North Carolina at Chapel Hill found that brain organoids — artificial models of the brain — developed from the cells of kids who have autism are often bigger than those grown from the cells of kids who don’t have autism, suggesting that dissimilar brain sizes could be linked to the activity of a type of cell known as neural progenitors.
As the model brains used for the research grew and developed, neural progenitors were less likely to differentiate in the organoids derived from kids with autism than they were in the organoids from neurotypical kids. Researchers think that this could be the reason behind brain overgrowth in some individuals with autism.
Other parts of the brain that may be enlarged in autism include the fusiform gyrus, which plays a key role in processing facial information, and the primary visual cortex.
I hope you’ve found this helpful!
Kirsten