The two most commonly diagnosed neurodevelopmental conditions in childhood share enough surface features that families — and sometimes clinicians — struggle to tell them apart. Inattention, social difficulties, emotional dysregulation, sensory sensitivity, intense focus on specific interests. Both autism and ADHD can produce all of these. Both are more common than most people realize. And both can exist in the same child at the same time.

The distinction matters — not because one diagnosis is better or worse, but because autism and ADHD have different core features, different diagnostic criteria, and different intervention needs. Understanding the difference between autism or ADHD, where they overlap, and how sensory issues fit into both pictures helps families advocate more effectively for accurate evaluation and appropriate support.

 

Autism spectrum disorder (ASD) is defined by two core domains: persistent differences in social communication and interaction, plus restricted or repetitive patterns of behavior, interests, or activities. Sensory differences are included in the diagnostic criteria as part of the restricted/repetitive behavior domain.

Attention deficit/hyperactivity disorder (ADHD) is defined by patterns of inattention and/or hyperactivity-impulsivity that impair functioning across settings. Sensory issues are not part of the formal diagnostic criteria for ADHD, but sensory sensitivities are observed in a significant portion of people with ADHD.

Co-occurrence is common and diagnosable. Before DSM-5 (2013), clinicians had to choose between an autism or ADHD diagnosis — both could not be given to the same person. DSM-5 eliminated this restriction. Research estimates 22–83% of autistic children also meet criteria for ADHD, and 30–75% of children with ASD show ADHD symptoms.

 

The DSM-5 Diagnostic Criteria: What Makes Each Condition Distinct

Both autism and ADHD are diagnosed using the DSM-5, the American Psychiatric Association’s diagnostic manual. Their core criteria are distinct — even where symptoms overlap on the surface.

Autism Spectrum Disorder Criteria (DSM-5)

Autism requires persistent deficits across two domains:

Domain A — Social communication and interaction:

  • Difficulty with social-emotional reciprocity (initiating or responding to social interaction)
  • Deficits in nonverbal communication (reduced eye contact, limited facial expressions, difficulty reading body language)
  • Challenges developing and maintaining relationships

Domain B — Restricted, repetitive behaviors (at least two required):

  • Stereotyped or repetitive motor movements, speech, or use of objects
  • Insistence on sameness, inflexible adherence to routines
  • Highly restricted, fixated interests of unusual intensity or focus
  • Hyper- or hyporeactivity to sensory input, or unusual interest in sensory aspects of the environment

Both domains must have been present in early development and cause clinically significant impairment.

 

ADHD Criteria (DSM-5)

ADHD requires a persistent pattern of inattention and/or hyperactivity-impulsivity:

Inattentive presentation: Difficulty sustaining attention, following through on tasks, organizing activities, avoiding tasks requiring sustained mental effort, and losing things. Easily distracted, frequently forgetful.

Hyperactive-impulsive presentation: Fidgeting, leaving seat when expected to remain seated, running or climbing in inappropriate situations, difficulty engaging in quiet activities, talking excessively, blurting answers, difficulty waiting, interrupting others.

Combined presentation: Features of both.

Symptoms must be present in multiple settings, have been present before age 12, and cause functional impairment.

Crucially: sensory processing differences are not part of the formal ADHD diagnostic criteria — unlike autism, where sensory reactivity is explicitly included in Domain B.

 

Side-by-Side: Autism vs ADHD Symptoms

Feature Autism (ASD) ADHD
Social communication Core deficit — difficulty with reciprocity, nonverbal cues, relationships Not a core deficit — social difficulties often secondary to impulsivity/inattention
Repetitive behaviors Core criteria (stimming, routines, restricted interests) Not core criteria — but some overlap in hyperfocus
Attention Can be impaired; often hyperfocused on specific interests Core deficit — inattention and/or hyperactivity-impulsivity
Sensory processing Formally included in diagnostic criteria Common but not part of formal diagnosis
Routine preference Strong preference for sameness; distress with change Generally novelty-seeking; may become bored with routine
Emotional regulation Often impaired; connected to sensory and social demands Often impaired; connected to impulsivity
Executive function Commonly impaired Core impairment
Special interests Intense, narrow, persistent Intense but often shifting over time
Language development May be delayed or atypical Typically age-appropriate, though word retrieval challenges can occur
Co-occurrence 22–83% also meet ADHD criteria 20–60% show ASD-like social difficulties

 

Where Autism and ADHD Overlap

The conditions share a significant number of features — which is why misdiagnosis, missed diagnosis, and diagnostic delay are all common in both populations.

What is the difference between Sensory Processing Disorder ADHD & Autism Denver Brain Health Expert

Executive Function Deficits

Executive function — the cognitive processes that manage planning, organization, flexible thinking, impulse control, and working memory — is commonly impaired in both autism and ADHD. This is one of the most documented areas of overlap. A child with executive function deficits may struggle with transitions, starting tasks, following multi-step instructions, and managing time — regardless of which diagnosis is primary.

Emotional Dysregulation

Both autistic children and children with ADHD frequently experience intense emotional responses that are difficult to regulate. In autism, this is often connected to sensory overload, social confusion, or disruption of routines. In ADHD, it is more closely linked to impulsivity and low frustration tolerance. The behavioral result — meltdowns, shutdowns, intense emotional outbursts — can look similar from the outside.

Hyperfocus

Both conditions can produce states of intense, sustained focus on specific activities or interests. In autism, special interests are typically narrow, persistent over long periods, and not particularly novelty-driven. In ADHD, hyperfocus tends to be more variable — shifting to new interests when novelty fades. The distinction between the two is clinically useful but not always immediately apparent.

Stimming and Repetitive Behaviors

Stimming — self-stimulatory repetitive behaviors like rocking, hand-flapping, pacing, or tapping — is formally associated with autism. However, people with ADHD also engage in repetitive movement, often as a regulatory tool for managing inattention and energy. The function is similar; the formal diagnostic attribution differs.

Social Difficulties

Social challenges appear in both conditions but for different reasons. In autism, social differences are often rooted in differences in social cognition — difficulty reading nonverbal cues, understanding social reciprocity, or navigating unwritten social rules. In ADHD, social difficulties more often stem from impulsivity (speaking before thinking, difficulty taking turns in conversation) and inattention (missing social cues because attention is elsewhere). The behavioral output can look similar; the underlying mechanism differs.

 

Are Sensory Issues Autism or ADHD?

This is one of the most commonly asked questions by families who are trying to make sense of a child’s sensory reactivity in the context of a diagnostic question.

The direct answer: Sensory processing differences are formally part of the autism diagnostic criteria (DSM-5, Domain B4). They are not formally part of the ADHD diagnostic criteria. However, sensory sensitivities are frequently observed in people with ADHD and are documented in the research literature as a commonly co-occurring feature — they are simply not required for a diagnosis.

What sensory issues look like in each condition:

In autism, sensory responses tend to be consistent, specific, and functionally significant. A child may be reliably hypersensitive to certain sounds (covering ears in specific situations), tactile inputs (distress about specific fabrics or food textures), or visual stimuli (reacting strongly to fluorescent lighting). Sensory-seeking behaviors — seeking vestibular input through spinning, or proprioceptive input through crashing and jumping — are also common. These sensory responses are typically stable across settings and have a clearly predictable pattern.

In ADHD, sensory sensitivity tends to be more variable and less predictably patterned. Children with ADHD may seek out sensory stimulation as a way of managing inattention — fidgeting, touching everything in the environment, difficulty staying still. They may also show some hypersensitivity, but it is less consistent than the sensory profiles typically seen in autism.

When sensory issues warrant evaluation: Any child who shows consistent, functionally impairing sensory responses — responses that affect their ability to participate in daily activities, educational settings, or social environments — deserves evaluation regardless of whether the eventual diagnosis is autism, ADHD, sensory processing disorder, or some combination. An occupational therapy evaluation and a comprehensive developmental assessment together provide the most complete picture.

The Dual Diagnosis: When It’s Both Autism and ADHD

Before 2013, clinicians could not diagnose both autism and ADHD in the same individual. The DSM-IV-TR explicitly excluded ADHD as a diagnosis when autism was present. The DSM-5 removed that exclusion — and the research since then has confirmed what many families and clinicians had already observed: co-occurrence is common, measurable, and clinically meaningful.

Research estimates 22–83% of autistic children also meet diagnostic criteria for ADHD. A 2016 population-based study found that 30–75% of children with ASD have ADHD symptoms. The range is wide because methodologies and sample populations vary — but the direction of the evidence is consistent.

Why the dual diagnosis matters for treatment:

A child with both autism and ADHD has a different support profile than a child with either condition alone. Executive function deficits are more pronounced. Emotional regulation challenges are compounded. The child may need both behavioral support through ABA — addressing the autism-related components of communication, behavior, and daily living — and additional ADHD-specific support, which may include behavioral strategies focused on attention and impulse management, environmental accommodations, and in some cases medication.

Missing the ADHD component in a child who has both conditions means missing a significant driver of their behavioral and educational challenges. Missing the autism component means providing inadequate support for the social, communicative, and sensory dimensions of their experience.

 

Getting an Accurate Diagnosis: What It Involves

An accurate differential diagnosis of autism or ADHD — or both — requires a comprehensive evaluation, not a questionnaire or brief office visit.

Components of a thorough evaluation:

  • Developmental history — detailed information about early development, language milestones, social development, and behavioral patterns from birth
  • Behavioral observations — direct observation of the child in structured and unstructured settings
  • Standardized assessment tools — for autism: ADOS-2 (Autism Diagnostic Observation Schedule), ADI-R (Autism Diagnostic Interview-Revised), or similar validated instruments; for ADHD: Conners Rating Scales, NICHQ Vanderbilt scales, or equivalent
  • Cognitive and adaptive assessments — measuring intellectual functioning and real-world adaptive behavior
  • Multi-informant reporting — parents, teachers, and other caregivers all provide behavioral information, as presentations can differ significantly across settings
  • Occupational therapy evaluation — for sensory processing assessment

A diagnosis of autism or ADHD from a single clinical visit without standardized assessment is incomplete. Families who have concerns about whether a diagnosis is accurate or complete can seek a second opinion from a developmental pediatrician, child neuropsychologist, or autism diagnostic specialist.

How ABA Therapy Supports Children With Autism (and Co-occurring ADHD)

ABA therapy is specifically designed for children with autism — addressing the behavioral, communicative, social, and adaptive skill dimensions of ASD. When a child has both autism and ADHD, ABA addresses the autism-related components of their profile directly.

In practice, this means:

  • Building functional communication skills — reducing reliance on challenging behavior to meet needs
  • Developing daily living skills and adaptive routines that accommodate both autism-related rigidity and ADHD-related executive function challenges
  • Implementing environmental supports — visual schedules, first-then boards, and structured routines that reduce cognitive load across both conditions
  • Parent training — equipping families with strategies that address the specific combination of autism and ADHD in their child’s profile
  • Generalization planning — ensuring skills transfer across home, school, and community settings

Children with a dual diagnosis of autism and ADHD often benefit from coordinated care between their ABA team, a behavioral pediatrician or psychiatrist (who may address the ADHD component with behavioral strategies or medication evaluation), and the school’s special education team.

Move Up ABA’s services include in-home ABA therapy, parent training, and school coordination — all structured around each child’s individual assessment, including their specific behavioral profile regardless of whether they carry one or two diagnoses.

 

Maryland and Virginia: Where the Research Meets Real Families

From the research-intensive communities surrounding the National Institutes of Health in Bethesda to the diverse school districts of Charles County and Harford County in Maryland — and from Arlington County through the outer commuter communities of Loudoun and Stafford counties in Virginia — families navigating autism or ADHD diagnoses, or both, live throughout the region Move Up ABA serves.

Our BCBAs are trained in the specific clinical picture that autism presents — and in how ADHD co-occurrence changes the intervention landscape. Programs are built on comprehensive assessment, individualized to the specific child’s profile, and adjusted continuously based on data.

Most major insurance plans cover ABA therapy for children with an autism diagnosis in both states. Coverage is verified before services begin.

 

Conclusion: The Diagnosis Is the Starting Point, Not the Destination

Autism or ADHD — the answer to that question shapes where a family looks for support, what services they access, and what expectations they bring to intervention. Getting it right matters.

What the research makes clear: these two conditions share significant features, frequently co-occur, and both require comprehensive evaluation to diagnose accurately. The DSM-5’s removal of the exclusionary criterion in 2013 was a significant clinical advance — it meant children with both conditions could finally receive support for both.

For families still waiting on evaluation, navigating a partial diagnosis, or wondering whether the picture has been fully assessed: pushing for completeness is always appropriate. A child who is autistic and has ADHD deserves support for both — not just the one that got named first.

If your child has an autism diagnosis and you’re building a behavioral support program, Move Up ABA starts with your child’s specific profile. Contact our team to discuss how we assess each child individually, design programs that reflect the full complexity of their needs, and work alongside families at every step.

Frequently Asked Questions

What is the difference between autism and ADHD? 

Autism’s core features are deficits in social communication/interaction and restricted or repetitive behaviors/interests. ADHD’s core features are inattention and/or hyperactivity-impulsivity. Both can produce social difficulties, attention challenges, emotional dysregulation, and sensory sensitivity — but through different underlying mechanisms.

Are sensory issues autism or ADHD? 

Sensory processing differences are formally included in autism’s diagnostic criteria (DSM-5). They are not part of ADHD’s formal criteria but are commonly observed in people with ADHD. A child showing significant sensory sensitivities deserves comprehensive evaluation regardless of which diagnosis is ultimately given.

Can a child have both autism and ADHD? 

Yes. The DSM-5 (2013) eliminated the previous restriction that prevented both diagnoses from being given to the same person. Research estimates 22–83% of autistic children also meet ADHD criteria.

How is autism diagnosed differently from ADHD? 

Both diagnoses require comprehensive evaluation using standardized tools. Autism assessment typically uses instruments like the ADOS-2 and ADI-R alongside developmental history. ADHD assessment relies on behavioral rating scales, multi-informant reporting, and observation across settings. Different professionals conduct these evaluations, though developmental pediatricians and child neuropsychologists are trained to assess both.

Does ABA therapy work for children with both autism and ADHD? 

ABA therapy is designed for autism. For children with both conditions, ABA addresses the autism-related components — communication, behavior, adaptive skills, social development. ADHD-specific components may also be addressed within ABA programming, and coordination with other providers (behavioral pediatricians, psychiatrists) is often valuable.

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