ADHD, Sensory Sensitivities, and Rigidity in Routine - Often Confused with Autism
When most people think of ADHD (Attention-Deficit/Hyperactivity Disorder), images of fidgety children and distracted adults come to mind. But ADHD is far more complex than just hyperactivity or inattention. Many individuals with ADHD experience sensory sensitivities and a strong preference for routine, traits more commonly associated with Autism Spectrum Disorder (ASD).
This symptom overlap can lead to confusion, misdiagnosis, or missed diagnosis altogether, especially in those whose symptoms don't fit conventional stereotypes. In this blog, we’ll examine the growing evidence that supports sensory and behavioural rigidity as part of the ADHD profile, and explore how to differentiate it from autism.
1. ADHD and Sensory Sensitivities: What the Research Says
While sensory processing differences are well-established in autism, they're increasingly recognised in ADHD as well.
Evidence:
A 2013 study published in Frontiers in Human Neuroscience found that children with ADHD had significantly more sensory processing difficulties than their neurotypical peers, particularly in areas of auditory filtering and tactile sensitivity (Shimizu et al., 2013).
Ghanizadeh (2011), in a review published in Neurosciences, reported that up to 46% of children with ADHD exhibit atypical sensory processing patterns.
Mangeot et al. (2001) found that children with ADHD were over-responsive to sensory stimuli and had difficulty modulating their responses, which could lead to emotional outbursts or withdrawal.
These sensory needs may stem from dysregulation in the prefrontal cortex and sensory integration areas of the brain, where individuals with ADHD may struggle to filter and prioritise sensory input.
2. Rigidity in Routine: Executive Dysfunction or Neurodivergent Need?
A strong preference for routine or resistance to change is often seen as a pronounced trait associated with autism. However, individuals with ADHD may also rely heavily on routines, not due to a need for sameness per se, but as a compensatory strategy for executive dysfunction.
Clinical Insight:
Executive functions — like planning, sequencing, and flexibility are typically impaired in ADHD. As a result, minor disruptions can cause significant stress or disorientation.
Barkley’s executive function theory (1997) suggests that difficulties in self-regulation and time management in ADHD make routines essential for functioning. Without structure, individuals may experience mental overload and chaos.
In contrast, autistic rigidity is often rooted in sensory comfort, anxiety reduction, or neurological processing differences around change (APA, DSM-5-TR, 2022).
So while both ADHD and autism may present with “rigid” behaviours, the underlying mechanisms differ. One is a coping tool; the other is more intrinsic to neurodevelopment.
3. Social and Diagnostic Overlap: ADHD or Autism? Or Both?
ADHD and autism are distinct diagnoses, but they frequently co-occur, and their overlapping traits can muddy the diagnostic waters.
1. Sensory Sensitivities
ADHD: May be inconsistent; sensory overload can lead to irritability or distraction.
Autism: Often persistent and pervasive; tied to routines, comfort, and regulation.
2. Need for Routine / Resistance to Change
ADHD: Routines help manage executive dysfunction; change causes disorganization or stress.
Autism: Routines provide predictability and reduce anxiety; change can trigger distress or shutdowns.
3. Emotional Dysregulation
ADHD: Quick to anger or excitement; emotions can be intense and fast-moving.
Autism: May experience slow-building emotions or shutdowns; struggles identifying or expressing feelings.
4. Executive Functioning Difficulties
Both: Trouble with planning, time management, task initiation, and organization.
5. Social Differences
ADHD: May be impulsive, talk over others, or misread social cues due to distractibility.
Autism: May struggle with social reciprocity, eye contact, or understanding unwritten rules.
6. Hyperfocus / Intense Interests
ADHD: Can hyperfocus sporadically, especially on novel or stimulating activities.
Autism: Deep, long-term focus on specific topics or activities; often passion-driven.
7. Stimming or Repetitive Behaviours
ADHD: Often fidgeting, tapping, or moving to stay engaged.
Autism: Repetitive movements (rocking, hand-flapping) for regulation or expression.
8. Difficulty With Transitions
ADHD: Can forget or lose track of transitions; may procrastinate or resist abrupt changes.
Autism: Transitions may feel disruptive or distressing; benefit from preparation and support.
9. Sleep Challenges
Both: Common issues with falling asleep, staying asleep, or circadian rhythm dysregulation.
10. Anxiety and Stress Sensitivity
Both: Higher baseline anxiety, often due to sensory overload, unpredictability, or social pressure.
Facts:
According to the CDC (2023), around 30–50% of autistic individuals also meet criteria for ADHD, and vice versa.
A 2020 study published in European Child & Adolescent Psychiatry found that 28% of children diagnosed with ADHD met the criteria for autism spectrum disorder based on parent-report questionnaires.
Girls are often underdiagnosed in both conditions due to masking, compensatory behaviour, and non-stereotypical presentations (Lai et al., 2015).
4. Why This Distinction Matters
Correct diagnosis leads to more effective interventions, accommodations, and self-understanding. Mislabelling someone can result in inappropriate therapies or missed strategies that would actually work.
A child misdiagnosed with autism instead of ADHD may be placed in programs that focus too heavily on social scripting, neglecting executive function support.
An adult with ADHD might be told they're “too sensitive” or “too rigid” without anyone recognising these as neurodevelopmental traits.
Acknowledging that ADHD can include sensory challenges and routine dependence helps validate diverse experiences within the ADHD community.
5. Practical Support Strategies
If you or someone you support has ADHD with these traits, here are evidence-based strategies:
🔊 For Sensory Sensitivities:
Use noise-cancelling headphones or earplugs in overwhelming environments.
Offer tactile tools or fidget items to redirect sensory-seeking behaviours.
Allow movement breaks or alternative seating in classrooms or workspaces.
📅 For Routine & Structure:
Build visual schedules or consistent daily frameworks.
Introduce transition warnings (e.g., “5 minutes until we switch tasks”).
Use apps or timers to support time management and reduce unpredictability.
These strategies are helpful regardless of whether the individual is diagnosed with ADHD, autism, or both.
📚 References
Shimizu, V. T., Bueno, O. F. A., & Miranda, M. C. (2013). Sensory processing abilities of children with ADHD. Frontiers in Human Neuroscience, 7, 324. https://doi.org/10.3389/fnhum.2013.00324
Ghanizadeh, A. (2011). Sensory processing problems in children with ADHD, a systematic review. Psychiatry Investigation, 8(2), 89–94. https://doi.org/10.4306/pi.2011.8.2.89
Mangeot, S. D., Miller, L. J., McIntosh, D. N., et al. (2001). Sensory modulation dysfunction in children with ADHD. Developmental Medicine & Child Neurology, 43(6), 399–406.
Barkley, R. A. (1997). ADHD and the nature of self-control. Guilford Press.
American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text revision; DSM-5-TR).
Lai, M. C., Lombardo, M. V., & Baron-Cohen, S. (2015). Autism. The Lancet, 383(9920), 896–910.
CDC. (2023). Data and statistics on ADHD. https://www.cdc.gov/ncbddd/adhd/data.html
Final Thoughts
Neurodevelopmental conditions are rarely black and white. ADHD, much like autism, exists on a spectrum and sensory needs or rigidity aren’t exclusive to one diagnosis. Understanding the why behind these behaviours leads to better compassion, support, and advocacy.
Let’s move past labels and toward deeper insight, because when we see the full picture, we can truly support the person.