Identifying ADHD and Autism in Kids Using Online Tests
From birth to the second decade of life, the brain continues to develop and mature. However, even slight disturbances to this developmental process can result in alterations in the function of this complex organ, producing what are known as neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). ADHD can be defined by increased inattention and distractibility, increased hyperactivity and impulsivity, or a combination of these symptoms, while the two defining characteristics of ASD are impaired social interaction and communication, and persistently restrictive and inflexible behaviours or activities, such as repeatedly arranging toys in a row. Both ADHD and ASD are relatively common in Canada, with the prevalence of ADHD in children being almost 8 in 100, and the prevalence of ASD in children being 2 in 100.
Cognitive impairments are common in children with ADHD or ASD and can be found in 30–60% of children with ADHD and in 40% of children with ASD. Cognitive impairments can potentially lead to social, emotional, behavioural, and academic difficulties; however, since shortcomings in cognitive skills can be improved through interventions, identification of specific cognitive deficits is crucial as it can allow for more individualized support (e.g., in planning, organization, or self-regulation) at home or school. While some common cognitive deficits such as information processing speed and short-term memory have been observed in child populations of ADHD and ASD, it is unknown if there are also cognitive deficits that are unique to either ADHD and ASD—and if these deficits can be used to distinguish between these populations.
To address this question, a study by Hennessy and colleagues at Western University adapted a collection of online cognitive tests to determine differences in cognitive abilities between children with ADHD, children with ASD, and typically developing children. The original set of 13 cognitive tests assessed a range of skills such as short-term memory, attention, logical reasoning, and verbal abilities, making it possible to assess and identify specific cognitive deficits. Since these tests were originally developed for adults, the original written instructions were revised and additional voiceovers of instructions were added to make the tests appropriate for children. These modified cognitive tests were then tested in 11 neurodivergent children with various diagnoses including ADHD, ASD, Obsessive Compulsive Disorder (OCD), and learning disorders, and in 6 typically developing children—all of whom were aged 4–11 years. After verifying the cognitive tests could be completed by every child, the tests were administered online to a larger sample of children within the ages of 4–16, 83 of whom had ADHD, 37 of whom had ASD, and 86 of whom who were typically developing.
Example of the Double Trouble (DT) task. Participants must determine the font colour of the top word (red) and pick the correct colour from the bottom two choices in rectangles (red in the bottom left rectangle). Modified from Wild and colleagues.
What Hennessey and colleagues found was that compared to typically developing children, children with ADHD did worse on two attention tasks: Double Trouble (DT) and the Sustained Attention to Response Task (SART). In DT, participants were presented with colour words that were written in conflicting font colours; for example, “red” written in a green colour. Participants would use focused attention and inhibition to select the colour of the font rather than the word itself, which is difficult because the normal tendency is to read the word.
Example of the Odd One Out (OOO) task. The “odd one out” in this example is the object in the middle column and middle row. Modified from Creyos.
The Sustained Attention to Response Task (SART) in contrast required participants to use more sustained attention to overcome a trained response (pressing a key) when presented with one infrequently appearing number out of 9 number options. For example, a single number from 1 to 9 would be presented on the screen, and when any number except 3 appeared, participants would press a key. Children with ADHD also did worse on a short-term memory task called Digit Span (DS), where participants had to memorize and correctly enter strings of numbers of increasing digit length until a mistake was made. For example, a sequence of 3 digits such as 9 2 6 would be displayed one at a time on a screen, and participants had to remember and re-entered this sequence of numbers onto a keyboard. If the sequence was entered correctly, the task would be repeated with a sequence of 4 digits. Conversely, children with ASD did worse on the reasoning task Odd One Out (OOO), where participants were presented with 9 objects and had to deduce which object was the “odd one out” based on various characteristics (e.g., shape, colour).
Finally, performance on these specific tasks (DT, SART, DS, OOO) was able to correctly identify 53% of the typically developing children, 57% of the children with ADHD, and 60% of the children with ASD.
An important and novel implication of these findings is that children with ADHD and children with ASD have unique, distinguishable, and testable cognitive deficits that can be identified at an early age. These differences in cognitive deficits can potentially help in early identification of ADHD and ASD in children, which is especially important since these diagnoses are often found together and are often misdiagnosed. Knowing the specific cognitive deficits found in ADHD and ASD can also help in developing more targeted interventions that can strengthen specific cognitive skills.
The results from Hennessey and colleagues should be investigated further to verify the cognitive deficits specific to ADHD and ASD and determine if these cognitive tests can be used in larger populations. If these findings are supported, these cognitive tests could be administered accessibly online as a simple, easy to implement, and inexpensive early screening tool for ADHD and ASD specific cognitive deficits in children. Through early identification of deficits in cognitive skills, children with ADHD and ASD can receive individualized support to develop skills that will ultimately promote future success through childhood, adolescence, and adulthood.
Original Article: Hennessy A, Nichols ES, Al-Saoud S, Brossard-Racine M, Duerden EG. Identifying cognitive profiles in children with neurodevelopmental disorders using online cognitive testing. Clinical Child Psychology and Psychiatry. 2024;29(2):591-607. doi:10.1177/13591045241228889