Sensory Modulation: Over-Responding, Under-Responding, and Seeking

What is sensory modulation?

Sensory modulation is the way the nervous system regulates its response to sensation, so that the strength and length of a reaction fit what is happening. Researchers describe it in terms of the duration, intensity and type of a person’s response to everyday sensory experiences, and its difficulties as responses that do not match the demands of the stimulus.⁠^2,18 People differ in how strongly and how quickly they respond to sensation; some have difficulty regulating those responses to a degree that interferes with daily activities.⁠¹⁰

That interference is measurable. In a study of 78 children, the 44 with sensory modulation disorder scored lower than their classmates on how well they performed everyday activities, how much they enjoyed them and how often they did them.⁠¹⁹

How is sensory modulation disorder defined?

In the proposed nosology, sensory modulation disorder means difficulty regulating responses to sensory stimulation: responding too much, too little, or by searching for more and stronger input.⁠¹ Ben-Sasson and colleagues define its best-studied form, over-responsivity, as responses that are rapid in onset, prolonged and greater in intensity than those of peers.⁠¹⁰ Lane and Reynolds describe sensory modulation disorders as an inability to respond to the environment in a way that matches the demands of the stimulus.⁠¹⁸

Sensory modulation dysfunction vs disorder: are they the same?

In practice, yes. The same research group wrote of sensory-modulation disruption in 1999 and sensory modulation dysfunction in 2001 for the pattern later set out as sensory modulation disorder.⁠^1,11,20 Terms keep shifting: the STAR Institute for Sensory Integration now writes of sensory modulation differences and suggests heightened responsivity and lowered responsivity as more neutral names for the two main patterns.⁠²¹

Where does sensory modulation disorder fit within SPD?

Sensory modulation disorder is one of three proposed categories in a nosology that Lucy Jane Miller and colleagues set out in 2006 and 2007: sensory modulation disorder, sensory discrimination disorder and sensory-based motor disorder.⁠¹ The scheme grew out of the sensory integration theory of the occupational therapist and researcher A. Jean Ayres, and its authors describe sensory processing disorder as a heterogeneous condition whose subtypes a person may combine.⁠^1,16

How do clinicians describe sensory modulation today?

Not always in the same words. The STAR Institute’s current table lists two modulation patterns, over-responsive and under-responsive, and calls them differences rather than a disorder.⁠²¹ Questionnaires built on Dunn’s model sort similar behaviors differently, into four quadrants: registration, seeking, sensitivity and avoidance.⁠¹⁶ The Cleveland Clinic still lists three types, including sensory craving.⁠¹⁵

What are the three types of sensory modulation disorder?

The proposed subtypes describe the direction of the mismatch: too much response, too little, or a drive for more input.⁠¹

• Over-responsivity: responding too much, for too long, or to weak input, so that ordinary sensations feel irritating, unpleasant or even painful.⁠^1,22
• Under-responsivity: responding too little, or needing very strong input to notice it; a child may seem quiet and passive, or not notice pain from bumps and scrapes.⁠^1,21
• Sensory seeking and craving: an intense search for more or stronger stimulation, which in the craving form leaves a person disorganized rather than satisfied.⁠^1,15

For the first two side by side, see over-responsivity vs under-responsivity.

What does the research show about sensory over-responsivity?

It is the most studied subtype.⁠¹ Children with over-responsivity may react with fear, avoidance, distraction, over-vigilance or aggression, especially when they did not start the sensation themselves.⁠¹⁰ In a representative birth cohort of 925 children aged 7 to 11, parents of 16.5% reported at least four touch or sound sensations that bothered their child; tags in clothing (39%), nail cutting (19%) and hair brushing (16%) were the most often named. Those children had more early and current social and emotional problems, by their parents’ report.⁠¹⁰

Over-responsivity often comes with other conditions: rates of 56% in autism and 69% in ADHD have been reported, and children with ADHD and over-responsivity more often had clinically significant anxiety than children with ADHD alone.⁠^10,18 It can extend to pain. Children with sensory modulation disorder rated pricking stimuli as more painful and felt the pain for longer, and a study comparing 91 adults with sensory modulation disorder with 60 without found heightened pain too.⁠^23,24

Measurement is still developing. The Sensory Over-Responsivity Scales pair an examiner-run assessment with a caregiver inventory across seven sensory domains, and in a pilot study they separated over-responsive from typical groups aged 3 to 55.⁠²⁵

What does the research show about sensory under-responsivity?

Under-responsivity means responding too little, or needing extremely strong input before noticing it.⁠¹ The STAR Institute describes people who seem quiet and passive or oblivious to ordinary input, who may not notice pain from bumps, falls or scrapes, and whose low response to touch and deep pressure may leave them clumsy, with poor body awareness.⁠²¹

Much of the research on it comes from autism. A meta-analysis of 14 studies found the largest difference between autistic and typical groups in under-responsivity, ahead of over-responsivity and seeking, and in a direct comparison, autistic children showed more under-responsivity than children with sensory modulation disorder.⁠^2,26 In fragile X syndrome too, under-responsivity has been reported more often than over-responsivity.⁠¹⁰

What does the research show about sensory seeking?

Sensory seeking describes an intense search for more or stronger stimulation.⁠¹ The Cleveland Clinic describes sensory craving as a need for stimulation that leaves a person disorganized and does not satisfy the craving.⁠¹⁵ When 40 autistic children were compared with 31 children with sensory modulation disorder, the children with sensory modulation disorder showed more atypical seeking.⁠²

Descriptions of seeking vary. A 2019 meta-analysis of 55 studies found large differences in all three subtypes between autistic and typical groups, but how large the difference in seeking was depended on age, IQ and whether people rated themselves; the STAR Institute’s current table lists only over- and under-responsivity as modulation patterns.⁠^21,27

Do the three patterns overlap?

Often. The authors of the nosology say a person may present with a combination of subtypes, and both clinical groups in the autism comparison included children with over-responsivity, under-responsivity and seeking.⁠^1,2 When one team analyzed 39 children with sensory modulation disorder statistically, the children grouped best by severity rather than by type.⁠²⁸ Most children with high over-responsivity in the birth cohort were bothered by touch alone; few were bothered by sound alone.⁠¹⁰

How common is sensory modulation disorder?

Estimates depend on the questionnaire and the cut-off. In a kindergarten survey, 13.7% of the 703 children whose parents responded met screening criteria for sensory processing disorders, or 5.3% of the 1,796 enrolled if every family that did not respond is counted as negative.⁠²⁹ One research team puts sensory modulation disorder at about 5% of children, and the Cleveland Clinic cites 1 to 3 in every 20 people for sensory processing disorder.⁠^15,23

Single assessments may overstate it. Among 978 twins assessed at 2 and 7 years, 75 had high over-responsivity only at age 2, 112 only at age 7, and 24, or 2.5%, at both ages; the authors call the single-time rates in the literature unrealistically high and propose 2.5% as an upper limit for the over-responsive subtype.⁠⁴

Is sensory modulation disorder an official diagnosis?

No. Sensory processing disorder and its subtypes are not recognized in the DSM-5-TR or the ICD-11.⁠³ In 2009 the DSM revision committee was considering sensory processing disorder for its next edition; it was left out of DSM-5, with all its subtypes, because of questions about the validity of the disorder.⁠^1,4 The American Academy of Pediatrics advises that sensory processing disorder generally should not be diagnosed, because there is no universally accepted framework for diagnosis.⁠⁹

Two classifications for young children do include it. The DC:0-5 manual recognizes sensory processing disorder as a diagnosable condition in children up to age 5, and the 2005 classification of the Interdisciplinary Council of Developmental and Learning Disorders listed over-responsivity as a subtype of sensory modulation disorder.⁠^3,10 In the DSM-5-TR and ICD-11, sensory reactivity appears only inside the autism criteria, as hyper- or hyporeactivity to sensory input.⁠^3,7,8

Why is sensory modulation disorder not in the DSM-5-TR?

Researchers on both sides name the same gaps. Ben-Sasson and colleagues list four: no formal diagnostic criteria, high rates in children with conditions such as autism, an unknown cause, and too little population data.⁠¹⁰ The American Academy of Pediatrics adds that it is unclear whether children’s sensory problems reflect a disorder of the sensory pathways or are characteristics of other developmental and behavioral conditions.⁠⁹ Proponents agree that an objective way to diagnose it, and to tell it apart from other conditions, is still needed.⁠¹

What does physiological research show about sensory modulation?

Since 1995, a network of researchers has tested whether children with sensory modulation difficulties respond differently in the body, not only in behavior, starting with the autonomic nervous system.⁠¹

What do skin conductance (electrodermal) studies show?

Electrodermal activity, small changes in skin conductance, reflects the sympathetic nervous system’s reaction to sensation.⁠¹⁸ In 1999, 19 children with sensory modulation disruption and 19 matched controls were given five kinds of stimulus ten times each. Four of the children with sensory modulation disruption did not respond at all; the rest showed more and larger responses than controls and habituated more slowly, and children with atypical responses had more unusual sensory behavior by their parents’ report.⁠¹¹

Later studies compared clinical groups. Children with ADHD showed more atypical sensory modulation than typical children on both skin conductance and parent report, and autistic children showed lower arousal and reactivity than children with sensory modulation disorder, who reacted more after each stimulus.⁠^2,20 Proponents point to a difference in pattern: children with ADHD reacted strongly to the first stimulus and then habituated, while children with over-responsivity kept reacting to every stimulus.⁠¹

What do heart rhythm and brain studies show?

Vagal tone, a heart-rhythm marker of parasympathetic activity, was lower in the 9 children with sensory processing difficulties than in the 6 typical children of a 15-child pilot study.⁠^12,28 A larger follow-up found only a trend for the whole group and a significant difference in the most severe subgroup.⁠²⁸ In EEG work with 28 children with sensory processing disorders and 25 typical children, the clinical group filtered out repeated sounds less well, and brain activity sorted the two groups with 86% accuracy.⁠¹³ An imaging study of 16 boys with sensory processing disorders found differences in posterior white matter.⁠¹⁴

What are the limits of the physiological evidence?

• Small samples. Groups of 19, 9 and 16 children are typical, and the imaging authors call their study exploratory and in need of replication.⁠^11,12,14
• One network, one clinic. Much of the work comes from one scientific work group, and the children with sensory modulation disorder in the autism comparison came from one private clinic near Denver.⁠^1,2
• Body and behavior do not always match. That comparison found no association between children’s physiological responses and their parent-reported sensory behavior in either group.⁠²
• Questionnaires overlap with other conditions. Many items on sensory modulation parent questionnaires overlap with the features of ADHD.⁠¹⁸
• Groups, not individuals. Group differences do not make a test for one child; there is no gold-standard assessment, and proponents still call for an objective diagnostic method.⁠^1,4

Proponents read the findings as support for the over- and under-responsive subtypes; the American Academy of Pediatrics’ view is that it remains unclear whether these problems reflect a disorder of the sensory pathways.⁠^1,9

How is sensory modulation disorder assessed?

By an occupational therapist, often after a pediatrician’s referral. The therapist watches the child respond to sensory experiences and asks about symptoms, behavior and medical history.⁠¹⁵ Researchers describe identification as resting on an expert’s overall clinical impression, informed by observation and by parent or teacher questionnaires; how sensory processing disorder is tested in children walks through the steps.⁠¹

Which questionnaires are used to assess sensory modulation?

The two most widely used questionnaires rest on different theories and agree only moderately to strongly: in 116 children, matching subscales correlated between 0.40 and 0.67. Both are meant to be one part of a fuller evaluation that includes observation and the family’s account.⁠¹⁶ No gold-standard assessment exists.⁠⁴

Why does an assessment look at other conditions?

Because sensory difficulties appear in many conditions. The American Academy of Pediatrics names autism, ADHD, developmental coordination disorder and childhood anxiety, and advises that other developmental and behavioral disorders always be considered in a thorough evaluation.⁠⁹ Sensory reactivity is part of the autism criteria, and over-responsivity is common in ADHD; see sensory processing and autism and ADHD vs sensory processing disorder.⁠^7,18

What is sensory modulation in occupational therapy?

The phrase has two uses. In pediatric occupational therapy it names a pattern a therapist assesses and treats, often with a sensory integration approach: goal-directed play in a multisensory setting, with swinging, jumping, pushing, pulling and deep pressure built into activities designed to tap the child’s own drive.⁠¹ More on that approach is in sensory integration therapy and SPD therapy and treatment.

In mental health care, sensory modulation names an intervention: sensory approaches that help people regulate physiological and emotional arousal. A scoping review of 17 studies found that people reported less distress, with mixed effects on seclusion and restraint and methodological limits throughout.⁠³⁰ In a case-control study of two psychiatric units, the unit that introduced sensory modulation used belts 38% less and forced medication 46% less than the comparison unit.⁠³¹

What helps with sensory modulation difficulties?

Support starts from what the child is trying to do: take part in class, get through a haircut, sit for a meal. Trials of occupational therapy judge success against goals set for each child, and children with sensory modulation disorder take part less in everyday activities than their peers.⁠^5,6,19 The aim is a better fit between the child and the surroundings, through sensory activities and practical changes such as headphones and planned movement breaks.⁠¹⁵

1. Notice what comes before a reaction. Over-responsive reactions are often strongest when a sensation is unexpected or one the child did not start.⁠¹⁰
2. Cut the input that overwhelms. Headphones for background noise and planned breaks for movement help some children at school.⁠¹⁵
3. Give sought-after input a safe outlet. Occupational therapists build swinging, jumping, pushing, pulling and deep pressure into play.⁠¹
4. Look twice at the quiet child. A child who seems passive and does not notice bumps or scrapes may be under-responsive rather than unbothered.⁠²¹
5. Ask about anxiety and mood as well. Over-responsivity goes with more anxiety in children with ADHD and more social and emotional problems by parents’ report.⁠^10,18
6. Agree on how progress is judged. The American Academy of Pediatrics suggests a trial period of therapy and teaching families how to evaluate whether it works.⁠⁹

What does OT research show for sensory modulation disorder?

A randomized pilot trial targeted sensory modulation disorder directly. Twenty-four children were assigned to occupational therapy with a sensory integration approach, an activity protocol or no treatment; the therapy group made significant gains on individual goals and on attention and cognitive and social measures, while changes on sensory questionnaires, behavior checklists and skin conductance were only trends. The authors used it to estimate the size of a larger multisite trial.⁠⁵

Most other trials studied autistic children. A 2018 systematic review found strong evidence that Ayres Sensory Integration improves individually set goals in autistic children, drawing on three randomized trials and two smaller studies.⁠⁶ A 2015 review separated that clinic-based therapy from classroom sensory-based strategies such as weighted vests, where few positive effects were found.⁠³²

What does the research not show?

It does not yet show that therapy changes the underlying sensory response: in the sensory modulation trial, questionnaire and physiological measures moved only as trends.⁠⁵ The strong evidence for individual goals comes from autistic children, not from sensory modulation disorder on its own.⁠⁶ The American Academy of Pediatrics describes research on sensory integration therapy as limited and inconclusive and suggests treating it as one part of a broader plan, with a defined trial period.⁠⁹ Larger trials with manualized protocols are still called for.⁠³²

Can adults have sensory modulation difficulties?

Yes. A sensory testing study compared 91 adults with sensory modulation disorder with 60 without and found heightened pain to prickling stimuli, in line with earlier findings in children; the Sensory Over-Responsivity Scales were piloted with people aged 3 to 55.⁠^24,25 See sensory processing in adults.

Sensory modulation disorder vs ADHD, autism and anxiety

It overlaps with all three, which is the center of the debate about whether it is a separate condition.⁠^9,10 In laboratory comparisons, children with ADHD habituated after a strong first reaction while children with over-responsivity kept reacting, and autistic children showed lower arousal and more under-responsivity while children with sensory modulation disorder reacted more and sought more input.⁠^1,2 Imaging researchers note that sensory processing difficulties often occur without another diagnosis.⁠¹⁴

Anxiety often comes with it. Children with ADHD and over-responsivity more often had clinically significant anxiety, and at a child mental health center, children with severe sensory processing alteration scored in the clinical range for anxious and depressed symptoms and for attention problems.⁠^3,18

Does sensory modulation disorder go away?

For many children, high over-responsivity does not last. In the twin study, scores correlated only modestly between ages 2 and 7, and far more children screened high at one age than at both.⁠⁴ Symptoms persisted more often in children born prematurely or with low birth weight, or with more fearful, less soothable temperaments, and the authors conclude that a valid diagnosis may need assessment over time; prematurity is among the causes and risk factors studied.⁠⁴ Adults can still have sensory modulation difficulties.⁠²⁴

When should you seek an assessment for sensory modulation?

When sensory reactions get in the way of daily life: school, friendships, self-care or family routines. Children with sensory modulation disorder take part in everyday activities less, and enjoy them less, than their peers.⁠¹⁹ The CDC’s advice to parents with any developmental concern is not to wait: share the concern with the child’s doctor and ask about screening.⁠³³ A pediatrician can refer to an occupational therapist, and occupational therapy providers are listed in the directory.⁠¹⁵

Relatedsensory processing overviewtypes of SPDinteroceptionstimming

Frequently Asked Questions

Sources

1. Miller LJ, Nielsen DM, Schoen SA, Brett-Green BA. Perspectives on sensory processing disorder: a call for translational research. Frontiers in Integrative Neuroscience. 2009;3:22. PMID 19826493. Checked October 11, 2026.
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   “The new nosology proposes three main categories within SPD: sensory modulation disorder (SMD), sensory discrimination disorder and sensory-based motor disorder. SMD refers to difficulty regulating responses to sensory stimulation and three subtypes are proposed: Sensory over-responsive (responds too much, for too long, or to stimuli of weak intensity); Sensory under-responsive (responds too little, or needs extremely strong stimulation to become aware of the stimulus); and sensory seeking/craving (responds with intense searching for more or stronger stimulation).” The nosology is attributed to “Miller, 2006; Miller et al., 2007a”, and “individuals may present with a combination of subtypes”. “Much of the new research is derived from a SPD Scientific Work Group (SWG)”; “The subtype that has been most studied by the SPD-SWG is SMD, particularly sensory over-responsivity (SOR) and sensory under-responsivity (SUR) subtypes.” In 2009, “the Diagnostic and Statistical Manual (DSM)-V revision committee is currently considering the inclusion of SPD into the ‘novel diagnoses’ section”. “Currently, identification of SPD is based on the global clinical impression of experts, who use information from observation or from screening tools that rely on parent or teacher report-measures such as the Sensory Profile ... and the Sensory Processing Measure”. “children with ADHD displayed atypically large reactions to the initial presentation of a sensory stimulus, but habituated following subsequent presentations of the stimuli ... This finding differentiated children with ADHD from children with SPD-SOR who had larger reactions to all stimuli and did not habituate to recurring sensory stimulation”. Treatment: “multisensory environments where challenging goal-directed activities are designed to provide specific sensory input”, such as “swinging (vestibular), jumping, pulling, pushing (proprioceptive) and deep pressure touch (tactile)”. “These studies support Ayres’ theories ... and validates the SOR and SUR subtypes in the current clinical nosology groupings”. “Activities are designed to be ‘fun’ and tap the inner drive of the child”. “Ayres was an occupational therapist and researcher”; “Sensory processing disorder is a heterogeneous condition that includes a variety of subtypes”; “Within sensory-based motor disorder two subtypes are proposed: Postural disorder, which reflects problems in balance and core stability, and dyspraxia, which encompasses difficulties in motor planning and sequencing movements. Sensory discrimination disorder refers to difficulty interpreting the specific characteristics of sensory stimuli (e.g., the intensity, the duration, the spatial, and the temporal elements of sensations”). “The first line of this phase of research, which started in 1995, examined physiologic mechanisms of autonomic nervous system regulation in response to sensory stimulation in children with SPD-SOR.” “Development of an objective method to diagnosis SPD and to differentiate it from other neurodevelopmental and neurobehavioral conditions is essential.”
2. Schoen SA, Miller LJ, Brett-Green BA, Nielsen DM. Physiological and behavioral differences in sensory processing: a comparison of children with autism spectrum disorder and sensory modulation disorder. Frontiers in Integrative Neuroscience. 2009;3:29. PMID 19915733. Checked October 11, 2026.
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   “Sensory Modulation Disorder, which is characterized by difficulty regulating one’s responses (i.e. duration, intensity, and/or type of response) in a flexible and adaptive manner to sensory experiences that occur in daily life”. Forty autistic children and “Thirty-one children with Sensory Modulation Disorder (SMD), ages 5–13 years”, the latter “recruited from the Sensory Therapies And Research (STAR) Center, a multi-disciplinary private clinic near Denver, CO”. “Physiological arousal and sensory reactivity were lower in children with ASD whereas reactivity after each sensory stimulus was higher in SMD”; “The ASD group had more taste/smell sensitivity and sensory under-responsivity while the SMD group had more atypical sensory seeking behavior.” “This study found no association between behavioral and physiologic measures of sensory processing for either the ASD or SMD groups.” “both clinical groups consisted of individuals with Sensory Over-Responsivity, Sensory Under-Responsivity and Sensory Seeking/Craving”; “the lack of a larger sample size in this study did not allow for exploration of differences by subtype”.
3. Valencia M, D’Ocon A, Plata R, Simo S, Cantero MJ. Internalizing/externalizing problems and sensory processing alteration in children referred to child mental health centers. Children (Basel). 2025;12(6):664. PMID 40564622. Checked October 11, 2026.
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   “children with severe SP alteration scored within the clinical range on the Anxious/Depressed and Attention Problems scales”. “Despite this body of evidence, SPD is not recognized in diagnostic classification systems such as the DSM-5-TR or ICD-11. SP alteration is only included as one of the criteria for restrictive and repetitive patterns of behavior, interests, or activities in the diagnosis of ASD (DSM-5-TR).” “An exception is the DC: 0–5 manual ..., which explicitly recognizes SPD as a diagnosable condition in children aged 0–5 years.”
4. Van Hulle C, Lemery-Chalfant K, Goldsmith HH. Trajectories of sensory over-responsivity from early to middle childhood: birth and temperament risk factors. PLoS One. 2015;10(6):e0129968. PMID 26107259. Checked October 11, 2026.
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   Twins “(N=978)” assessed at two and seven years: “low symptom (N=768), remitted (N=75), late-onset (N=112), and chronic (N=24)”; “Sensory over-responsivity was modestly correlated across ages ”; “symptoms were more stable among children born prematurely or who had more fearful and less soothable temperaments”; “Children in the chronic group had a younger gestational age and were more likely to be low birth-weight than the low symptom group.” “A clear implication is that assessment over development may be necessary for a valid sensory processing disorder diagnosis”. “SPD (and all subtypes) was ultimately excluded from the most recent edition of the DSM ... due to questions over the validity of the disorder”; “No ‘gold standard’ assessment for sensory processing disorders exists”; “the prevalence rates cited above appear unrealistically high”; “We think that the 2.5% estimate for the percentage of children who experience high levels of symptoms across development is a better benchmark for upper-limit prevalence of a SOR subtype of SMD than the higher estimates in the literature that are based on single age assessments.”
5. Miller LJ, Coll JR, Schoen SA. A randomized controlled pilot study of the effectiveness of occupational therapy for children with sensory modulation disorder. American Journal of Occupational Therapy. 2007;61(2):228-238. PMID 17436845. Checked October 11, 2026.
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   The abstract: “Twenty-four children with SMD were randomly assigned to one of three treatment conditions; OT-SI, Activity Protocol, and No Treatment.” “The OT-SI group, compared to the other two groups, made significant gains on goal attainment scaling and on the Attention subtest and the Cognitive/Social composite of the Leiter International Performance Scale-Revised. Compared to the control groups, OT-SI improvement trends on the Short Sensory Profile, Child Behavior Checklist, and electrodermal reactivity were in the hypothesized direction.” “In addition, sample size estimates for a large scale, multisite RCT were calculated.”
6. Schaaf RC, Dumont RL, Arbesman M, May-Benson TA. Efficacy of occupational therapy using Ayres Sensory Integration: a systematic review. American Journal of Occupational Therapy. 2018;72(1):7201190010p1-7201190010p10. PMID 29280711. Checked October 11, 2026.
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   The abstract: “Three randomized controlled trials, 1 retroactive analysis, and 1 single-subject ABA design published from 2007 to 2015, all of which happened to study children with autism, met inclusion criteria. The evidence is strong that ASI intervention demonstrates positive outcomes for improving individually generated goals of functioning and participation as measured by Goal Attainment Scaling for children with autism.”
7. Centers for Disease Control and Prevention. Clinical Testing and Diagnosis for Autism Spectrum Disorder. Page dated May 8, 2025, reproducing the DSM-5 criteria. Checked October 11, 2026.
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   Criterion B.4: “Hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment (e.g. apparent indifference to pain/temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement).”
8. World Health Organization. 6A02 Autism spectrum disorder. ICD-11 for Mortality and Morbidity Statistics, release 2026-01, with the clinical descriptions and diagnostic requirements. Checked October 11, 2026.
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   Essential features include “Lifelong excessive and persistent hypersensitivity or hyposensitivity to sensory stimuli or unusual interest in a sensory stimulus, which may include actual or anticipated sounds, light, textures (especially clothing and food), odors and tastes, heat, cold, or pain.” Boundary with Oppositional Defiant Disorder: “oppositional or ‘demand avoidant’ behaviour may be prominent in some children with Autism Spectrum Disorder, whether or not they have accompanying intellectual or functional language impairments and may sometimes be the presenting feature in school-aged children with Autism Spectrum Disorder.” Outbursts “are often associated with a specific trigger (e.g., a change in routine, aversive sensory stimulation, anxiety, or rigidity ...), rather than reflecting an intention to be defiant, provocative, or spiteful”.
9. Zimmer M, Desch L; Section on Complementary and Integrative Medicine; Council on Children with Disabilities; American Academy of Pediatrics. Sensory integration therapies for children with developmental and behavioral disorders. Pediatrics. 2012;129(6):1186-1189. PMID 22641765. Checked October 11, 2026.
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   The abstract: “it is unclear whether children who present with sensory-based problems have an actual ‘disorder’ of the sensory pathways of the brain or whether these deficits are characteristics associated with other developmental and behavioral disorders. Because there is no universally accepted framework for diagnosis, sensory processing disorder generally should not be diagnosed. Other developmental and behavioral disorders must always be considered, and a thorough evaluation should be completed. Difficulty tolerating or processing sensory information is a characteristic that may be seen in many developmental behavioral disorders, including autism spectrum disorders, attention-deficit/hyperactivity disorder, developmental coordination disorders, and childhood anxiety disorders.” “Occupational therapy with the use of sensory-based therapies may be acceptable as one of the components of a comprehensive treatment plan. However, parents should be informed that the amount of research regarding the effectiveness of sensory integration therapy is limited and inconclusive.” Clinicians may talk “with families about a trial period of sensory integration therapy, and teaching families how to evaluate the effectiveness of a therapy”.
10. Ben-Sasson A, Carter AS, Briggs-Gowan MJ. Sensory over-responsivity in elementary school: prevalence and social-emotional correlates. Journal of Abnormal Child Psychology. 2009;37(5):705-716. PMID 19153827. Checked October 11, 2026.
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    “Individuals differ in their response to sensation in aspects such as the type, intensity, affective tone of response, and the onset and offset of response. Further, some individuals evidence clinically significant difficulties regulating their response to sensation to a degree that sensory responses interfere with participation in daily activities.” “A pattern of extreme sensory over-responsivity (SOR) is defined as a type of sensory modulation disorder (SMD) manifested by behavioral responses to sensory input that are rapid in onset, prolonged, and greater in intensity compared to peers”; children “may show negative responses to specific sensations, in the form of fear, avoidance, distraction, over-vigilance, and/or aggression especially when the stimulus is not self-initiated”. A birth-cohort sample “(n=925, 50% boys, ages 7–11 years)”: “16.5% (n= 148) of children in this study had SOR scores that were above this cutoff (i.e., at least four bothering sensations)”; “tags in clothing (39%), cutting finger or toe nails (19%), hair brushing (16%)”; of those above the cutoff, “76.4% (n=113) had only elevated tactile scores, 6.8% (n=10) had only elevated auditory scores, and 16.9% (n=25) had both”. “The controversy surrounding the diagnosis of SOR is influenced by (1) an absence of formal diagnostic criteria, (2) high prevalence among children with developmental disorders such as autism spectrum disorders ..., (3) unknown etiology, and (4) lack of epidemiological evidence”; “SOR was included as a subtype of SMD under the umbrella of Sensory Processing Disorders (SPD) in the classification of the Interdisciplinary Council of Developmental and Learning disorders (ICDL 2005)”. Clinical groups: “(e.g., 56% Ben-Sasson et al. 2007)” in autism and “ADHD (e.g., 69%; Parush et al. 2007)”; “In certain disorders such as ASD ... and Fragile-X ... sensory under-responsivity, which is another type of SMD, was even more prevalent than SOR.” “parents of children with versus without elevated SOR at school age reported more early and concurrent social-emotional problems”; the measure was “limited by relying upon a single parent informant and focusing on only two sensory modalities”.
11. McIntosh DN, Miller LJ, Shyu V, Hagerman RJ. Sensory-modulation disruption, electrodermal responses, and functional behaviors. Developmental Medicine and Child Neurology. 1999;41(9):608-615. PMID 10503919. Checked October 11, 2026.
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    The abstract: “Nineteen children with clinically identified disruptions, aged 3 to 9 years, mean 6.0 years, and 19 age- and sex-matched healthy (control) children”; “Four children with SMD did not show electrodermal responses (EDR) to stimulation; all control children responded. Excluding non-responders, children with SMD showed more and larger EDR than control children. Participants with disruptions habituated more slowly to repeated stimulation”; “Children with atypical EDR had more parent-reported abnormal behavioral responses to sensation.”
12. Schaaf RC, Miller LJ, Seawell D, O’Keefe S. Children with disturbances in sensory processing: a pilot study examining the role of the parasympathetic nervous system. American Journal of Occupational Therapy. 2003;57(4):442-449. PMID 12911086. Checked October 11, 2026.
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    The abstract: “Participants were 15 children, nine with disturbances in sensory processing and six typically developing children.” “Children with disturbances in sensory processing had significantly lower vagal tone than the typically developing sample”; “Although the number of subjects in this pilot study is small”.
13. Davies PL, Gavin WJ. Validating the diagnosis of sensory processing disorders using EEG technology. American Journal of Occupational Therapy. 2007;61(2):176-189. PMID 17436840. Checked October 11, 2026.
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    The abstract: “28 children with sensory processing disorders (SPD) and 25 children who were typically developing, ages 5-12 years”; “Children with SPD demonstrated less sensory gating than children who were typically developing. A significant relationship between sensory gating and age was found in children who were typically developing but not in children with SPD. Brain activity correctly distinguished children with SPD from children who were typically developing with 86% accuracy.”
14. Owen JP, Marco EJ, Desai S, et al. Abnormal white matter microstructure in children with sensory processing disorders. NeuroImage: Clinical. 2013;2:844-853. PMID 24179836. Checked October 11, 2026.
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    “DTI was acquired in 16 boys, 8–11 years old, with SPD and 24 age-, gender-, handedness- and IQ-matched neurotypical controls.” “Significant decreases in FA and increases in MD and RD were found in the SPD cohort compared to controls, primarily involving posterior white matter”. “This exploratory investigation of white matter microstructure in SPD is limited by small sample size and needs to be replicated in larger cohorts.” “assessments of sensory processing, MSI and inattention were based on the Sensory Profile, a parent questionnaire”; “There is co-morbidity with attention deficit hyperactivity disorder (ADHD), autism and other psychopathology, but SPD often exists in isolation”.
15. Cleveland Clinic. Sensory Processing Disorder (SPD). Health Library, last updated March 20, 2025. Checked October 11, 2026.
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    “Currently, SPD isn’t an official medical diagnosis.” “Researchers estimate that about 1 to 3 out of every 20 people in the general U.S. population have sensory processing disorder.” “Sensory craving (SC). In this type, you need and seek out sensory information for stimulation. But getting the stimulation results in disorganization and doesn’t satisfy the craving.” “your child’s pediatrician may refer you to an occupational therapist. These professionals can assess your child for SPD by watching them interact with certain sensory experiences. They’ll also ask about your child’s symptoms, behavior and medical history”; at school a child may need “Access to headphones to block out background noises while they work” and “A designated break to do a sensory activity, like walking, spinning or swinging”.
16. Gandara-Gafo B, Beaudry-Bellefeuille I. Convergent validity of two sensory questionnaires in Spain: Sensory Profile-2 and Sensory Processing Measure. Children (Basel). 2023;10(9):1516. PMID 37761476. Checked October 11, 2026.
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    “Sensory integration theory was developed by A. Jean Ayres”. “Sensory reactivity is assessed mostly by using sensory questionnaires; the most widely used in Spain are the Sensory Profile-2 (SP-2) ... and the Sensory Processing Measure (SPM)”; “Both questionnaires are designed to be used together with other evaluation tools, personal narratives as well as clinical observations, as part of a comprehensive evaluation”; “the SP-2 is built on the sensory processing model of Dunn ..., whereas the SPM is closely aligned with the constructs and pattens identified within ASI”; SP-2 items fall in “four sensory quadrants (registration, seeking, sensitivity, and avoidance)”; the SPM home version “includes 75 items designed to assess behavioral responses related to vision, hearing, touch, taste & smell, body awareness, and balance & motion, as well as praxis (planning & ideas)” and “a section on social participation”; “The SP-2 ... and the SPM ... have a home and school version.” In 116 children, matching subscales correlated from “moderate (r = 0.401, p < 0.001)” to “strong (r = 0.674, p < 0.001)”.
17. World Health Organization. ICD-11 2022 release. News item, February 11, 2022. “ICD-11 is now officially in effect for the national and international recording and reporting of causes of illness, death - and more.” Checked October 11, 2026.
18. Lane SJ, Reynolds S. Sensory over-responsivity as an added dimension in ADHD. Frontiers in Integrative Neuroscience. 2019;13:40. PMID 31555103. Checked October 11, 2026.
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    “SMDs are characterized by an inability to respond to environmental stimuli in a way that matches the demands of the stimulus”; “many of the questions on the SMD parent-report tools include behaviors that overlap with the diagnostic features associated with ADHD (e.g., emotional and social responses, activity levels)”; “children with ADHDs more frequently exhibited anxiety within a clinically significant range than did children with ADHDt” (ADHD with and without sensory over-responsivity); “we suggest sensory over-responsivity as a dimension in the diagnostic process for children with ADHD”; “EDR reflects the sympathetic nervous system reaction to sensation”.
19. Bar-Shalita T, Vatine JJ, Parush S. Sensory modulation disorder: a risk factor for participation in daily life activities. Developmental Medicine and Child Neurology. 2008;50(12):932-937. PMID 19046186. Checked October 11, 2026.
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    The abstract: “Participation in childhood daily functional performance was examined in 78 children: 44 with sensory modulation disorder (SMD)”; “Children with SMD scored significantly lower on all three participation scales than the control group.” The scales: “level of activity performance, level of enjoyment of the activity, and frequency of performance of the activity”
20. Mangeot SD, Miller LJ, McIntosh DN, McGrath-Clarke J, Simon J, Hagerman RJ, Goldson E. Sensory modulation dysfunction in children with attention-deficit-hyperactivity disorder. Developmental Medicine and Child Neurology. 2001;43(6):399-406. PMID 11409829. Checked October 11, 2026.
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    The abstract: “Twenty-six children with ADHD ... and 30 typically developing children”; “Compared to the typical sample, the children with ADHD displayed greater abnormalities in sensory modulation on both physiological and parent-report measures. The children with ADHD also displayed more variability in responses. Within the group with ADHD, levels of SMD were highly correlated with measures of psychopathology on the CBCL.”
21. STAR Institute for Sensory Integration. Patterns or Subtypes of Differences in Sensory Integration & Processing. Patterns page. Checked October 11, 2026.
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    Its table lists, under “Sensory Modulation Differences” (“Neural level processes that modulate/regulate responses to sensory stimuli”), two patterns: “Sensory Over-Responsive”, “Predisposition to respond more intensely, quicker, and/or longer to sensory stimuli”, and “Sensory Under-Responsive”, “Predisposition to respond less intensely to sensory stimuli, to have a delay before responding, and/or responses are muted.” “A more neutral term might be heightened responsivity”; “A more neutral term might be lowered responsivity.” Over-responsive people “often have a ‘fight or flight’ response to sensation”; under-responsive people “may appear quiet and passive, oblivious or not responding to stimuli of the usual intensity” and “may not notice pain in response to bumps, falls, cuts, or scrapes”; “Their under-responsivity to tactile and deep pressure input may lead to poor body awareness, clumsiness or movements that are not graded appropriately.”
22. Bar-Shalita T, Granovsky Y, Parush S, Weissman-Fogel I. Sensory modulation disorder (SMD) and pain: a new perspective. Frontiers in Integrative Neuroscience. 2019;13:27. PMID 31379526. Checked October 11, 2026.
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    “The sensory over-responsivity (SOR) subtype of SMD is manifested clinically as a condition in which non-painful stimuli are perceived as abnormally irritating, unpleasant, or even painful.” “such brain responses to sensory stimuli have correctly distinguished children with SMD from typically developing children and adults with 77%–96% accuracy”; pain is “a sensory modality not yet part of the official SMD realm”.
23. Bar-Shalita T, Vatine JJ, Seltzer Z, Parush S. Psychophysical correlates in children with sensory modulation disorder (SMD). Physiology & Behavior. 2009;98(5):631-639. PMID 19815022. Checked October 11, 2026.
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    The abstract: “Sensory modulation disorder (SMD), affecting approximately 5% of children”; “Seventy eight children aged 6-10 years (44 SMD children and 34 classmate controls)”; “These results indicate, for the first time, that children with SMD perceive more pain, and that their pain lasts longer.”
24. Bar-Shalita T, Vatine JJ, Parush S, Deutsch L, Seltzer Z. Psychophysical correlates in adults with sensory modulation disorder. Disability and Rehabilitation. 2012;34(11):943-950. PMID 22149534. Checked October 11, 2026.
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    The abstract: “One hundred and fifty one adults (68 males and 83 females) were tested comparing 91 SMD to 60 SMD-free, control individuals.” “individuals with SMD showed significantly higher pain intensity to prickle stimuli”; “These results are in line with our previous study that investigated children with SMD using the same stimuli, and found similar results.”
25. Schoen SA, Miller LJ, Green KE. Pilot study of the Sensory Over-Responsivity Scales: assessment and inventory. American Journal of Occupational Therapy. 2008;62(4):393-406. PMID 18712002. Checked October 11, 2026.
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    The abstract: “The SensOR Scales include the SensOR Assessment, an examiner-administered performance evaluation, and the SensOR Inventory, a caregiver self-rating scale. Both scales measure sensory overresponsivity in 7 sensory domains.” Participants were “ages 3 to 55”; the research edition showed “significant discrimination between the overresponsive and the typically responsive groups”.
26. Ben-Sasson A, Hen L, Fluss R, Cermak SA, Engel-Yeger B, Gal E. A meta-analysis of sensory modulation symptoms in individuals with autism spectrum disorders. Journal of Autism and Developmental Disorders. 2009;39(1):1-11. PMID 18512135. Checked October 11, 2026.
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    The abstract: “Results from 14 studies indicated a significant high difference between ASD and typical groups in the presence/frequency of sensory symptoms, with the greatest difference in under-responsivity, followed by over-responsivity and sensation seeking.”
27. Ben-Sasson A, Gal E, Fluss R, Katz-Zetler N, Cermak SA. Update of a meta-analysis of sensory symptoms in ASD: a new decade of research. Journal of Autism and Developmental Disorders. 2019;49(12):4974-4996. PMID 31501953. Checked October 11, 2026.
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    The abstract: “Fifty-five questionnaire studies included 4606 individuals with ASD.” “Compared to typical controls, effect size was large and significant for SOR, SUR, and Seeking but heterogeneous. For Seeking, age, IQ and self-report were significant moderators.” “compared with other clinical groups, only SOR was significant.”
28. Schaaf RC, Benevides T, Blanche EI, et al. Parasympathetic functions in children with sensory processing disorder. Frontiers in Integrative Neuroscience. 2010;4:4. PMID 20300470. Checked October 11, 2026.
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    Vagal tone “is frequently used in the literature as a non-invasive marker of PsNS activity”. “as a total group the children with severe SMD demonstrated a trend for low baseline PsNS activity, compared to TYP children”; “the severe SMD group had significantly lower PsNS activity at baseline, tones and prolonged auditory”. “For this analysis 39 SMD subjects were included”; “The best statistical fit for the SMD group was a three class latent class model that grouped subjects by severity of sensory dysfunction”; “Miller grouped subjects by type (over-responsive, under-responsive and seeking) using cluster analysis methodology whereas our data grouped best by severity”. “the number of subjects in the subgroup analyses is small”; “this study utilized a convenience sample of children with SMD”.
29. Ahn RR, Miller LJ, Milberger S, McIntosh DN. Prevalence of parents’ perceptions of sensory processing disorders among kindergarten children. American Journal of Occupational Therapy. 2004;58(3):287-293. PMID 15202626. Checked October 11, 2026.
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    The abstract: “A total of 703 completed surveys were returned, which represents 39% of the kindergarten enrollment (n = 1,796)”; “96 children (13.7% of 703) met criteria for sensory processing disorders based upon parental perceptions”; a cautious estimate of “5.3% (96 of 1796)”; “Findings suggest a need for rigorous epidemiological studies of sensory processing disorders.”
30. Scanlan JN, Novak T. Sensory approaches in mental health: a scoping review. Australian Occupational Therapy Journal. 2015;62(5):277-285. PMID 26358506. Checked October 11, 2026.
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    The abstract: “Sensory approaches in mental health are designed to assist consumers to regulate physiological and emotional arousal.” “A total of 17 studies were included in the final review.” “In general, consumers reported reductions in distress associated with engaging in sensory interventions. Results in terms of reduction of seclusion and restraint were mixed”; “Methodological limitations in the studies reviewed mean that results should be interpreted with caution.”
31. Andersen C, Kolmos A, Andersen K, Sippel V, Stenager E. Applying sensory modulation to mental health inpatient care to reduce seclusion and restraint: a case control study. Nordic Journal of Psychiatry. 2017;71(7):525-528. PMID 28719249. Checked October 11, 2026.
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    The abstract: “Sensory-based interventions promote adaptive regulation of arousal and emotion.” “The study included two similar psychiatric units where one unit implemented SM and one unit served as the control group.” “The use of belts decreased with 38% compared to the control group. The use of forced medication decreased with 46% compared to the control group.”
32. Case-Smith J, Weaver LL, Fristad MA. A systematic review of sensory processing interventions for children with autism spectrum disorders. Autism. 2015;19(2):133-148. PMID 24477447. Checked October 11, 2026.
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    The abstract: “A total of 19 studies were reviewed: 5 examined the effects of sensory integration therapy and 14 sensory-based intervention.” “Sensory-based interventions are characterized as classroom-based interventions that use single-sensory strategies, for example, weighted vests or therapy balls, to influence a child’s state of arousal. Few positive effects were found in sensory-based intervention studies.” “additional rigorous trials using manualized protocols for sensory integration therapy are needed”.
33. Centers for Disease Control and Prevention. CDC’s Developmental Milestones. Learn the Signs. Act Early. Page dated February 17, 2026. Checked October 11, 2026.
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    “Don’t wait. If your child is not meeting one or more milestones, has lost skills he or she once had, or you have other concerns, act early. Talk with your child’s doctor, share your concerns, and ask about developmental screening.”

Medical disclaimer. This page is for general educational purposes and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider about your child. Sensory and motor concerns are best assessed by an occupational or physical therapist who can evaluate your individual child.