Brain Function of Individuals with Autistic Spectrum Disorder

ASD (autistic spectrum disorder) is a condition that modifies the way people interact socially; how they communicate with one another, their interests and their behaviour. Common disorders on this scale are Asperger's syndrome and high functioning autism. ASD usually begins in childhood but the effects cannot be seen until a major change takes place, such as the changing of schools or moving to a different house.


There is no apparent cure for ASD but some effective treatments have been found to help minimise its effects. Unlike most disorders, autism is a spectrum disorder meaning that an individual can be anywhere from mildly autistic to extremely autistic. There is a saying that strongly relates to this, that is once you’ve seen one person with autism, you’ve seen one person with autism; that is to say: autism can beseen as unique to each person.Albert 1 There are, however, differences between people with and without ASD which are to do with the structure of the brain.

In the UK alone, there are around 700,000 reported cases of autism: that’s around 1 in every 100 people. The most recent study, conducted in 2011, shows that 1.1% of the population was diagnosed with autism, which means (more explicitly) there were 695,000 reported cases. Breaking these data down, it can be seen that 1 in every 68 children have been identified with ASD, with boys being 5 times more likely to have it, compared to girls. In the USA (reported 2008), 1 in 6 children was diagnosed with developmental disorders ranging from speech difficulties to cerebral palsy and autism.

The structure of the brain is specific to the way humans function every day and any modifications to the brain result in different outcomes. Most behavioural differences are due to chemical imbalances (i.e. Parkinson’s disorder, depression) but sometimes are caused by physical changes

Brain 1 (i.e. in autism).

In individuals without autism, there is a structure called the corpus callosum: this is a bundle of tracts connecting one hemisphere (side) of the brain to the other hemisphere. Interestingly, despite the fact that there is no corpus callosum in adults with autism, children still have one - albeit smaller than normal. The difference in corpus callosum size and its presence could be due to genetics: it has been found that afflicted individuals tend to have larger and more copy number variants (CNVs), which are deletions or duplications of DNA. With large chunks of DNA missing, the gene that codes for the corpus callosum doesn’t work effectively, which results in a small or even no callosum. 

People with Asperger's syndrome also have structures that are different compared to individuals without affliction. In individuals with Aspergers, there was a significant amount of grey matter missing. Grey matter is made up of unmyelinated cell bodies of neurons, which results in the grey colour. There was also impairment in sensorimotor gating, which in turn leads to people having difficulty controlling repetitive thoughts, speech and actions.

There are several tell-tale signs that show whether or not someone has ASD:

1) Language

Speech development tends to be delayed in affected individuals (for example, not speaking many words by a certain age or even not speaking at all). The speech also tends to sound monotonous and particular words are often repeated.


2) Responding and Interacting

Children with ASD have a habit of not replying when their name is called, despite having normal hearing. Some types of intimacy, such as hugging, can be rejected by children if initiated by others but can occur if initiate by the individual child. They tend to be unaware of personal space and it is common for them not to interact with other children at young ages.

Boy 2

3) Behaviour

Rocking back and forth tends to be commonplace in children with ASD, as is flicking of fingers and fidgeting. They prefer working around a familiar routine and become upset if it is changed. Another behaviour seen in ASD individuals is the intense disliking of certain foods, solely based on their colour or texture.

Albert 2