ASD or ADHD? Understanding the Differences to Better Support
Practical guide to distinguish autism spectrum disorder from ADHD and manage comorbidity
Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD): two neurodevelopmental conditions that may seem similar at first glance, but which present fundamental differences. However, it is not uncommon for a child to have both diagnoses, making understanding and support more complex. How to distinguish them? What are the common points? How to adapt support when ASD and ADHD coexist? This guide provides clear and practical answers.
ASD and ADHD: two distinct neurodevelopmental disorders
Both ASD and ADHD belong to neurodevelopmental disorders, meaning they appear in childhood and result from atypical brain development. However, the areas of the brain involved and the characteristic symptoms differ significantly.
of the global population has ASD
of children have ADHD
of autistic children also have ADHD
What is ASD?
Autism spectrum disorder is characterized by two main dimensions: persistent difficulties in communication and social interactions, and restricted and repetitive behaviors, interests, or activities. Autism is called a "spectrum" because it encompasses a vast diversity of profiles, ranging from non-verbal individuals requiring constant support to highly autonomous individuals with subtle differences.
🧩 Main characteristics of ASD
- Atypical communication: difficulty understanding nuances, sarcasm, facial expressions, and body language
- Different social interactions: preference for solitude or awkward social interactions, difficulty making friendships
- Intense specific interests: absorbing passions in restricted areas (trains, dinosaurs, mathematics...)
- Need for routine and predictability: anxiety in the face of unexpected events and changes
- Sensorial peculiarities: hypersensitivity or hyposensitivity to sounds, lights, textures, smells
- Repetitive behaviors: motor stereotypies (rocking, hand-flapping), unchanging rituals
What is ADHD?
ADHD manifests through three main symptoms: inattention (difficulty maintaining focus), motor hyperactivity (constant fidgeting, difficulty staying seated), and impulsivity (acting without considering consequences). These symptoms must be present in multiple contexts (home, school, leisure) to make the diagnosis.
⚡ Main characteristics of ADHD
- Sustained inattention: difficulty concentrating on long tasks, frequent forgetfulness, distractibility
- Motor hyperactivity: constant need to move, difficulty remaining seated, persistent restlessness
- Impulsivity: hasty responses, interrupting others, difficulty waiting for one's turn
- Disorganization: loss of items, chaotic time management, forgetting appointments
- Procrastination: difficulty starting boring tasks, need for immediate stimulation
- Fragile emotional regulation: rapid mood swings, low tolerance for frustration
Comparison Table ASD vs ADHD
To better visualize the differences and similarities, here is a summary table of the main characteristics.
| Domain | ASD | ADHD |
|---|---|---|
| Attention | Hyperfocus on specific interests, can concentrate for hours on what fascinates them | General difficulty concentrating, except for temporary hyperfocus on stimulating activities |
| Hyperactivity | Repetitive stereotyped movements (rocking, hand-flapping) to self-regulate | Constant fidgeting, need for overall movement, difficulty staying still |
| Social interactions | Difficulty understanding implicit social codes and forming connections | Understands social codes but violates them due to impulsivity |
| Communication | Sometimes atypical language (very formal or very literal), difficulty with non-verbal communication | Tends to talk a lot and quickly, interrupts due to impulsivity |
| Routine | Strong need for routine, anxiety in the face of even minor changes | Seeks novelty, quickly becomes bored with routine |
| Sensoriality | Marked hyper or hyposensitivity (textures, sounds, lights) | Less frequent, but can exist to a lesser degree |
| Organization | Can be very organized in their areas of interest, ritualized | Global disorganization, frequent loss of items, chaotic management |
| Empathy | Empathy present but expressed differently, difficulty communicating it | Empathy present, but impulsive reactions may seem insensitive |
| Neurological origin | Atypical brain connectivity, altered processing of social information | Dysfunction of attention and inhibitory control circuits |
Similarities that Complicate Diagnosis
ASD and ADHD share some seemingly similar symptoms, making differential diagnosis difficult, especially in young children. Here are common points of confusion.
🎯 Attention Difficulty
In ASD: The autistic child may seem not to listen when spoken to, but this is often because they are intensely absorbed in their activity of interest. They can remain focused for hours on a subject they are passionate about (always building the same puzzle, aligning objects).
In ADHD: The ADHD child has fluctuating and distractible attention in almost all contexts, except during very stimulating activities (video games, sports). Their concentration quickly wanes on monotonous tasks.
🏃 Motor Restlessness
In ASD: Repetitive movements (flapping, rocking, spinning) are stereotyped, ritualized, and serve to self-regulate in the face of intense emotion or sensory overload.
In ADHD: Restlessness is global, disordered, without a specific purpose: the child fidgets, gets up, fiddles with everything within reach because they need to expend overflowing energy.
💬 Verbal Impulsivity
In ASD: The child may abruptly interrupt a conversation because they are following their internal thought process without understanding that they need to wait their turn to speak. They may also monopolize the conversation on their topic of interest.
In ADHD: The child interrupts purely out of impulsivity: the thought bursts into their head and immediately comes out of their mouth, without filter or inhibitory control.
🤝 Social Difficulties
In ASD: The child does not understand implicit social rules (physical distance, eye contact, tone of voice). They may seem indifferent to others or awkward in their attempts to interact.
In ADHD: The child understands social rules but violates them due to impulsivity (talks too loudly, moves too much, makes jokes at inappropriate times). They may be rejected by peers due to their intrusive behavior.
⚠️ Caution in Differential Diagnosis
Only a qualified professional (child psychiatrist, specialized neuropsychologist) can diagnose ASD or ADHD. A comprehensive assessment includes standardized tests, observations in natural situations, questionnaires for parents and teachers, and sometimes additional examinations. Do not rely on self-diagnosis or symptom lists found on the internet: each child is unique and requires individualized evaluation.
Comorbidity of ASD + ADHD
For a long time, the DSM-IV diagnostic manual prohibited simultaneously diagnosing ASD and ADHD. This rule was abandoned in the DSM-5 (2013) as research has shown that 30 to 80% of autistic children also present with ADHD. This comorbidity is now recognized and taken into account in care pathways.
Why is this comorbidity so frequent?
Several hypotheses exist to explain this high co-occurrence. First, ASD and ADHD share common genetic bases: certain genes simultaneously increase the risk of developing either disorder. Second, similar brain anomalies (notably in the frontal areas responsible for executive control and attention) are observed in both conditions. Finally, autistic children, due to their constant cognitive overload in navigating an incomprehensible social world, may secondarily develop attention difficulties.
"My son Leo was first diagnosed with ADHD at age 6. We implemented a medication treatment that improved his attention, but his social difficulties persisted. It was only at 9 years old that a new assessment revealed he was also an Asperger autistic. Everything became clear: his need for routines, his obsessive interests in planets, his difficulty understanding jokes. Today, we adapt support to both diagnoses and he is doing much better."
How to support a child with ASD + ADHD?
When both diagnoses coexist, support must be specifically adapted and cannot simply add the usual strategies for ASD and ADHD. Some approaches may even contradict each other and require adjustments.
🎯 Specific adaptations for ASD + ADHD
- Flexible routine: The ASD child needs predictability, but the ADHD child quickly gets bored. Solution: create a reassuring basic structure with defined "novelty zones" (structured free time)
- Sensory AND motor management: Offer regular active breaks (ADHD need) in a calming sensory environment (ASD need)
- Dynamic visual supports: Use visual schedules (ASD need) with modifiable elements and possible choices (ADHD need)
- Targeted medication: Stimulants (methylphenidate) can be effective for ADHD but must be prescribed cautiously as they can increase anxiety in some autistic children
- Social skills AND impulsivity: Work on both understanding social codes (ASD) and inhibitory control (ADHD) through role-playing and social scenarios
Adapted Support Strategies
At Home
🏠 Daily Arrangements
- Create dedicated spaces: calm zone for self-regulation (ASD), active zone to let off steam (ADHD)
- Use visual timers to materialize the remaining time before a transition
- Offer limited choices: "Would you prefer to shower now or in 10 minutes?" (ADHD autonomy + ASD predictability)
- Anticipate changes with visual supports and social scenarios
- Allow sensory objects (fidgets, weighted items) to channel restlessness
- Value strengths: visual memory, creativity, passion for certain subjects
- Maintain a regular rhythm of meals and sleep to stabilize mood
At School
Educational Adaptations
Written + oral instructions, extra time, breaking down long tasks, use of computers
Spatial Arrangement
Seat near the board, away from distractions, access to a calm space for breaks
Time Management
Visual timetable, warning of activity changes, use of timers
Social Support
Explicit teaching of social skills, peer tutoring, social skills groups
COCO: Cognitive Stimulation for Children with ASD and ADHD
The COCO program from DYNSEO is particularly suited for children with ASD, ADHD, or both. The cognitive games work on attention, memory, reasoning, and executive functions in a playful and progressive manner. The clear interface without visual overload is suitable for autistic children sensitive to stimuli. Mandatory sports breaks every 15 minutes meet the movement needs of ADHD children. No time pressure, no possible failure: the child progresses at their own pace with confidence.
Discover COCOThe Role of Health Professionals
Supporting a child with ASD and/or ADHD involves a multidisciplinary team. Each professional brings their specific expertise.
👨⚕️ Professionals to Consult
- Child Psychiatrist: diagnoses, prescribes medication if necessary, coordinates care
- Neuropsychologist: conducts a complete cognitive assessment, identifies strengths and weaknesses
- Specialized Psychologist: works on social skills (CBT, TEACCH for ASD, cognitive remediation for ADHD)
- Speech Therapist: rehabilitates pragmatic language (ASD) and reading (often associated dys disorders)
- Psychomotor Therapist: works on sensory regulation, motor coordination, body awareness
- Occupational Therapist: proposes practical adaptations, organizational tools, school adaptations
- Specialized Educator: supports the child in daily and social activities
Medication: What You Need to Know
The question of medication often divides families. It is important to understand that while no medication "cures" ASD or ADHD, some treatments can significantly improve quality of life by reducing certain symptoms.
For ADHD
Psychostimulants (methylphenidate: Ritalin, Concerta, Quasym) are the first-line treatment for ADHD. They improve attention and reduce impulsivity in about 70-80% of children. Contrary to popular belief, these medications do not "drug" the child or change their personality: they correct a neurochemical imbalance (deficit in dopamine and norepinephrine) that prevents the brain from regulating attention normally.
For children who cannot tolerate stimulants or in case of contraindications, atomoxetine (Strattera) or guanfacine may be proposed. The decision to medicate should always result from a thorough discussion between parents, the child (if age-appropriate), and the doctor, weighing benefits and possible side effects.
For ASD
There is no specific medication for autism. However, some treatments can target associated symptoms such as intense anxiety (SSRIs), aggression, or severe self-injurious behaviors (atypical antipsychotics like risperidone), or sleep disorders (melatonin).
These medications are only prescribed if the targeted symptoms significantly impair the child's and family's quality of life, and always in addition (never as a replacement) to psycho-educational support.
"Medication is neither mandatory nor miraculous. It is a tool among others. What matters is to respect the child's pace, to value their unique strengths, and to create an environment that allows them to thrive as they are."
Prognosis and Evolution
ASD and ADHD are permanent conditions that accompany the person throughout their life. However, with early diagnosis and appropriate support, the evolution can be very favorable.
For ADHD, symptoms of motor hyperactivity generally diminish in adolescence, but inattention and impulsivity often persist into adulthood. Many adults with ADHD develop effective compensatory strategies and lead fulfilling lives, particularly in creative or dynamic professions that value their fast and innovative thinking.
For ASD, the prognosis heavily depends on language level, cognitive abilities, and the timeliness of intervention. Verbal autistic children with normal or high IQ (formerly Asperger syndrome) generally have a good social and professional prognosis, even if some peculiarities persist. Intensive early intervention programs (ABA, TEACCH, Denver) significantly improve the social and adaptive skills of young children.
Every Child is Unique
ASD and ADHD are not rigid labels, but frameworks for understanding a child's functioning. Behind these diagnoses lies a unique person, with their strengths, challenges, and distinct personality. No autistic child is like another autistic child. No ADHD child is identical to another.
The goal of support is not to "normalize" the child to make them resemble others, but to give them the tools to navigate a world designed for neurotypical brains, while celebrating what makes them unique. Children with ASD and ADHD have extraordinary abilities: overflowing creativity, exceptional visual memory, original thinking, and contagious passion for their subjects of interest.
As parents, teachers, or professionals, our role is to adapt the environment to their specific needs, to value their successes, and to support them with patience and kindness towards autonomy and flourishing.
