Autism vs ADHD: what's the difference?

Autism spectrum disorder (ASD) is characterized by social communication challenges (e.g., difficulty reading social cues) and restricted/repetitive behaviors (e.g., intense interests or sensory sensitivities) [1]. ADHD primarily involves inattention (e.g., distractibility), hyperactivity (e.g., fidgeting), and impulsivity (e.g., interrupting) [11]. While both are neurodevelopmental, autism relates more to how information is processed, whereas ADHD relates to regulating attention and impulses [9].

Symptom overlap includes executive dysfunction (e.g., planning difficulties) and sensory sensitivities [6]. Up to 40.2% of autistic people also meet ADHD criteria [12]. The term AuDHD describes this co-occurrence, where traits interact uniquely—for example, ADHD impulsivity may clash with autism’s need for routine [2,4]. Misdiagnosis is common, especially in girls who mask symptoms [10].

Yes. AuDHD is recognized clinically, though diagnostic criteria historically discouraged dual diagnoses [7]. Studies suggest shared genetic and neurological factors, but the conditions manifest differently: ADHD may drive novelty-seeking, while autism often involves routine preference [3,11]. The National Geographic notes brain structure differences in co-occurring cases [3].