The IQ of Autistic Children: Understanding Cognitive Diversity on the Spectrum. Dr Nadeem Ghayas
April 14, 2025
Autism spectrum disorder is a neurological and developmental disorder that affects how people interact with others, communicate, learn, and behave. Although autism can be diagnosed at any
age, it is described as a “developmental disorder” because symptoms generally appear in the first two years of life. People with autism have a wide range of symptoms, which can include
differences in social and communication behaviors, intellectual disabilities, and other physical and mental health conditions.
People with autism also have a wide range of health care and basic service needs. Research shows that access to needed services and supports early in life can promote people’s health and well-being over the long term.
Intelligence Quotient(IQ), is defined as a score that measures how a person’s thinking and problem-solving
skills compare to others of the same age. IQ tests usually look at skills such as understanding language, memory, reasoning, and visual thinking. Some of the common IQ tests include the
Wechsler Intelligence Scale for Children (WISC), the Stanford-Binet Intelligence Scales, and Raven’s Progressive Matrices. These tests were originally are for people without developmental conditions, so they may not fully capture the thinking
styles of autistic children.
In the past, autism was often linked to intellectual disability. In the 1960s and 1970s, studies such as one by Rutter (1970) reported that up to 75% of autistic children had IQ scores below 70, which is considered to show an intellectual disability. This led many professionals, teachers, and families to believe that all autistic children had low intelligence. But this idea was based on tests that didn’t consider the unique ways autistic children learn and communicate. For example, nonverbal children couldn’t answer questions that relied on spoken words, and sensory issues like noise or bright lights often made it hard for them to focus. These tests also ignored areas
where many autistic children are strong, like visual thinking or pattern recognition. As a result, many children were misjudged and misunderstood.
Today, research gives much clearer picture. A study conducted by Charman et al. (2011) found that only about 31% of autistic children have an intellectual disability. In contrast, 45% have average or even above-average IQ scores. Similar results were reported by the Centers for
Disease Control and Prevention (CDC, 2020), showing that more and more autistic children are being identified without having intellectual disabilities. These changes are likely due to better
testing tools and more awareness of the diversity within autism.
One of the most important things to understand is that autistic children often have uneven abilities. This is called a “spiky profile,” meaning they might be very strong in one area and struggle in another. For example, some children may have a low verbal IQ (trouble with
language) but a high performance IQ, doing well on tasks that involve solving puzzles or recognizing patterns. Research using nonverbal tests like Raven’s Progressive Matrices has
shown that many autistic children who score low on verbal tasks actually perform very well on visual tasks (Dawson et al., 2007). This highlights the importance of using a variety of tests to
understand a child’s true potential.
Many factors can affect how well an autistic child does on an IQ test. One important factor is communication. Some children are nonverbal or speak very little, so they may not be able to
respond to questions that require spoken answers. This doesn’t mean they don’t understand—it just means they may not be able to show what they know in that moment or in that format. Another important factor is sensory sensitivity. Testing rooms with bright lights, background noise, or unfamiliar people can be overwhelming for autistic children, causing stress or distraction during the test. When a child is uncomfortable or anxious, their test scores may not reflect their true abilities.
Traditional IQ tests also include tasks based on social and language skills, like understanding a short story or identifying feelings from facial expressions. These tasks may not match how autistic children process information. Even if a child is very good at problem-solving or logical
thinking, they might score low on these social-based questions. This can give a false impression of their overall intelligence. That’s why many experts recommend using flexible and
personalized approaches to testing, so that each child’s strengths and needs are fairly considered.
Another fascinating part of autism is the presence of splinter skills or savant abilities in some children. These are rare but amazing talents in areas like math, memory, music, or art. A child
might struggle with everyday tasks but have an incredible memory or be able to play music by ear. Some can read at a very young age (a skill known as hyperlexia) or remember calendar
dates for years into the future. These skills remind us that intelligence comes in many forms and can’t always be measured by a standard test (Treffert, 2009). Understanding the different ways that autistic children think and learn has big implications for education and therapy. It’s important for schools to create Individualized Education Plans
(IEPs) that reflect each child’s specific abilities. Teaching strategies should focus on what a child can do, not just what they find hard. For example, using visual aids, assistive technology, or alternative communication tools can help children succeed in the classroom. A strength-
based approach can build confidence and help children reach their full potential. It’s also important to move beyond just using IQ as the main measure of ability. While IQ can
provide useful information, it should not be the only factor when making decisions about diagnosis, support, or school placement. Instead, looking at a child’s adaptive functioning—how they manage daily life, interact socially, and solve real-world problems—can give a better picture of their abilities and needs.
References
1. Charman, T., Pickles, A., Simonoff, E., Chandler, S., Loucas, T., & Baird, G. (2011). IQ
in children with autism spectrum disorders: Data from the Special Needs and Autism
Project (SNAP). Psychological Medicine, 41(3), 619–627.
2. Dawson, M., Soulieres, I., Gernsbacher, M. A., & Mottron, L. (2007). The Level and
Nature of Autistic Intelligence. Psychological Science, 18(8), 657–662.
Lord, C., Brugha, T. S., Charman, T., Cusack, J., Dumas, G., Frazier, T., et al. (2020).
Autism spectrum disorder. Nature Reviews Disease Primers, 6(1), 1–23.
3. Rutter, M. (1970). Autistic children: Infancy to adulthood. Seminars in Psychiatry, 2(4),
435–450.
4. Treffert, D. A. (2009). The savant syndrome: An extraordinary condition. A synopsis:
past, present, future. Philosophical Transactions of the Royal Society B: Biological
Sciences, 364(1522), 1351–1357.
5. Centers for Disease Control and Prevention (CDC). (2020). Data & Statistics on Autism
Spectrum Disorder.