The brain remains one of the most mysterious parts of our anatomy. It’s still fresh territory. Scientists make new discoveries about how we process information almost every day. One area of recent focus in the brain has been with Autism Spectrum Disorder. Characterized as a complex neurodevelopmental condition, autism influences how the brain grows and processes information. Having an understanding of its impact on brain development provides insight into the unique strengths and challenges faced by children with autism in Markham.

Below are ten key ways brain development is affected by autism.

1. Altered Sensory Processing

There’s a reason that children with autism are more sensitive to light and sound. The way a brain with ASD accesses and processes information is simply different. For instance, it has been shown that neurodivergent children sometimes have more difficulty with the automatic processing of information. Because of this, they may rely more heavily on attention and working-memory based networks (which are often overloaded). The way the mind is wired, when stimuli reach and exceed capacity, the processing system fails. This is a problem for autistic individuals. Children with ASD often process sensory input in a unique way due to atypical development in sensory areas of the brain. These specific differences can lead to heightened sensitivity to sounds, textures, or lights, or, conversely, reduced sensitivity, affecting their interaction with the environment.

2. Atypical Mirror Neuron Activity

An observable characteristic of children with autism is that they often engage in solo or parallel play as opposed to interactive play with others. This is due to differences on a neural level. Mirror neurons have a part in the imitation and understanding of other people’s actions. They often function differently in children with neurodivergence. It can be harder for children to learn through observation and empathize with the emotions of others as a result of this atypical activity. Researchers have found that there is a definite neural interaction between mirror neurons, action perception, empathy, imitative behaviour, and their impact on social decision making in children with autism. 

3. Reduced Corpus Callosum Connectivity

The firing of neurons between the two sides of the brain is affected in children with autism. The strip along the middle of the brain is called the corpus callosum. It connects the brain’s left and right hemispheres. It is the essential piece of our anatomy that enables communication between the two separate, highly specialized sections. The corpus callosum is smaller in older children and adults with autism spectrum disorder. This has been shown through numerous brain imaging studies. Additionally, studies show that children with ASD may have reduced connectivity in this structure. This leads to challenges in integrating sensory information or coordinating complex tasks.

4. Impaired Neural Migration

There are specified areas of the brain where certain neurons should be. With autism sometimes they find themselves lost in the wrong section. For neurotypical children, neurons migrate to their proper locations during early brain development. In children with ASD, this process may be disrupted, resulting in atypical organization of brain structures. These neural disruptions can affect social, cognitive, and sensory processing. Scientists have found that most, if not all, individuals with ASD have defects in neuronal migration in certain regions of the brain. However, in most children with autism, neuronal migration deficits are mild.

5. Differences in the Amygdala

There may be a link to autism-related anxiety and the way it shapes the brain. The amygdala, a region critical for processing emotions and social cues, often shows atypical development in children with ASD. Neuropathological findings support the notion that overgrowth during early childhood followed by slowed growth can contribute to difficulties with emotional regulation and interpreting social interactions.

6. Hyperplasticity

It has been shown that children with autism have brain growth that occurs at a different speed. Many children with neurodivergence show increased brain volume during early development, especially in the frontal cortex. This rapid growth, known as hyperplasticity, can lead to overstimulation. Researchers have found that this creates challenges in processing sensory or social information. Plasticity is essential. We need it for the establishment and maintenance of brain circuitry. There are limits to it however. Too much plasticity can lead to a destabilization of structural connections. Excess growth can compromise functional systems necessary for cognition and behaviour.

7. Altered Synaptic Connectivity

Children with autism often exhibit differences in the formation and pruning of synapses, which are the connections between neurons. These changes may result in either an overabundance or a lack of neural connections. These alterations affect how efficiently the brain communicates across regions and within those regions. There is actually a drug that can restore normal synaptic pruning. It has been shown to improve autistic-like behaviours in mice. Scientists have found that this occurs even when the drug is given after the behaviours have appeared.

7. Abnormalities in the Cerebellum

The cerebellum in the area of the brain primarily associated with balance and complex motor functions. However it also has links to language processing and memory. It has recently been discovered that the cerebellum contributes to cognitive functions and the social brain. Accordingly, its involvement in the autistic brain has become unmistakable. In children with ASD. Structural or functional differences in the cerebellum can contribute to challenges with motor skills, focus, and adaptability to new situations.

9. Imbalanced Excitatory and Inhibitory Neural Activity

The brain has a way of self-regulating itself, but sometimes this internal system doesn’t work the way it was intended. For example, the brain relies on a balance of excitatory (stimulating) and inhibitory (calming) neural signals. In children with autism, this balance is sometimes disrupted. This imbalance leads to either heightened excitability or reduced inhibition. This can affect learning, behaviour, and sensory regulation. Distinct genetic forms of autism are believed to share a recurring increase in excitation-inhibition balance in the cerebral cortex. This can cause instances of hyperexcitability and excess spiking. 

10. Challenges in Default Mode Network (DMN) Functioning

There are many areas of the brain that are affected by autism spectrum disorder. Recent work has signified that certain functioning processes are also affected as well. For example, the DMN is a network of brain regions active during self-reflection and rest. Scientists have been able to consistently demonstrate that the DMN is among the most disrupted functional networks in the brains of those with autism. In children with neurodivergence, the DMN often shows reduced connectivity, impacting their ability to engage in introspection, plan future actions, or understand the perspectives of others.

No two children with autism spectrum disorder are alike. The condition manifests itself differently from child to child. In fact, the unique brain development patterns in children with ASD highlight the diversity of the spectrum. This emphasizes the importance of individualized support strategies. It’s important to nurture each child’s particular strengths while addressing their challenges. At Monarch House we have a professional, interdisciplinary staff of occupational therapists, behavioural therapists, psychotherapists, and speech pathologists that are here to help by fostering understanding and embracing neurodiversity. Working together with parents, educators, and caregivers, we can help children with autism in Markham thrive.