Autism Spectrum Disorder vs. ADHD

Key Differences

Difficulty concentrating
Autism Spectrum Disorder: Associated
ADHD: Core
Explanation: In ADHD, concentration problems are more central and persistent across tasks, while in autism they are more likely to appear as a secondary difficulty rather than the main issue.
Impulsivity
Autism Spectrum Disorder: Associated
ADHD: Core
Explanation: Impulsive actions or speaking before thinking are much more central to ADHD, while they are less defining in autism.
Difficulty understanding social cues
Autism Spectrum Disorder: Core
ADHD: Common
Explanation: In autism, missing facial expressions, tone, or unspoken social rules is more central and persistent, while in ADHD social difficulties may come more from attention, timing, or impulsive responding.
Being Extremely Sensitive to Bright Lights
Autism Spectrum Disorder: Core
ADHD: Associated
Explanation: Strong, ongoing sensitivity to bright light is more characteristic of autism, while in ADHD it is less central and usually not as defining.
Risk-taking behaviour
Autism Spectrum Disorder: Uncommon
ADHD: Core
Explanation: Risk-taking is much more typical of ADHD, especially when driven by impulsivity or stimulation-seeking, and is not a defining feature of autism.

Key Similarities

Symptom How it is similar
Hyperfocus Both autism and ADHD can involve becoming deeply absorbed in an activity or interest, making it hard to shift attention away.
Difficulty starting or finishing tasks Both can make task initiation and follow-through difficult, even when the person wants to complete the task.
Feeling emotionally overwhelmed Both can involve intense emotional overwhelm, especially when demands, stress, or stimulation feel difficult to manage.
Difficulty making or keeping friends Both can affect friendships and social connection, even when the person wants relationships.
Restless or poor-quality sleep Both can be associated with ongoing sleep difficulties that leave the person feeling unrested.
1 of 14