Sensory sensitivity: understanding the test and better supporting your child with autism

Understanding sensory sensitivity: definition and neurological mechanisms

Sensory sensitivity refers to how the central nervous system processes, filters, and integrates information from the sensory organs. When this integration functions atypically — processing too much information (hyperreactivity), not enough (hyporeactivity), or inconsistently — it is referred to as sensory processing peculiarities or sensory integration disorder. These peculiarities can affect any of the seven sensory systems recognized today: vision, hearing, touch (tactile system), taste (gustatory), smell (olfactory), proprioception (awareness of body position in space), and the vestibular system (balance and movement).

Neurologically, sensory processing involves complex brain networks organized hierarchically. The sensory organs capture stimuli. Afferent pathways transmit them to specialized cortical regions (visual, auditory, somatosensory cortex...). The thalamus plays a central role as a "filter" or "doorman" — it regulates what proportion of sensory information accesses the cortex. The prefrontal cortex and other associative regions integrate this information into a coherent perception and link it with past experiences and expectations. The amygdala evaluates the emotional valence of sensory stimuli — it can trigger a stress response to a sensory stimulus perceived as threatening, even if that stimulus is not objectively dangerous.

Hypersensitivity and hyposensitivity: the two faces of sensory peculiarity

Hypersensitivity (or sensory hyperreactivity) is characterized by a lowered perception threshold — stimuli that seem neutral or harmless to most people trigger an intense, uncomfortable, or even painful response. A moderate sound perceived as deafening, a clothing label felt as a persistent scratch, the fluorescent light of a classroom experienced as blinding — these experiences are real, not exaggerated. Hyposensitivity (or sensory hyporeactivity) is the opposite: a high perception threshold that requires intense stimulation to be reached. A child who bumps against walls without seeming to feel it, who constantly needs intense movements, who compulsively chews on all objects within reach — often seeks sensory stimulation that is intense enough to "calibrate" their nervous system.

The same child can be hypersensitive in certain modalities (auditory, tactile) and hyposensitive in others (proprioceptive, vestibular) — this mixed profile is actually very common in ASD. Situational fluctuation adds an additional layer of complexity: the same child may be more or less sensitive depending on their level of fatigue, anxiety, stress, or the background level of the sensory environment. A child who tolerates music well in a quiet room may be in sensory overload in a busy restaurant even if the music is quieter there.

The Winnie Dunn model: four quadrants of sensory processing

The sensory processing model developed by neuropsychologist Winnie Dunn (1997) is one of the most influential theoretical frameworks in this field. It organizes sensory processing patterns according to two axes: the neurological threshold (high or low) and the behavioral response (passive or active). The intersection of these two axes generates four profiles: sensory seeking (high threshold, active response: the child seeks intense stimulation), sensory avoiding (low threshold, active response: the child actively flees or controls stimuli), sensory sensitivity (low threshold, passive response: the child is easily disturbed without seeking to avoid), and low sensory registration (high threshold, passive response: the child does not react to ordinary stimuli). This model allows for a nuanced description that goes beyond the simple hypersensitive/hyposensitive dichotomy.

The DYNSEO Sensory Sensitivity Test

What the test measures and how to interpret it

The DYNSEO Sensory Sensitivity Test explores each of the main sensory systems through questions about behaviors and reactions observed in daily life. For each sensory modality, the test identifies whether the profile leans towards hypersensitivity, statistical norm, or hyposensitivity. The resulting profile outlines a sensory map that can guide environmental adaptations, support strategies, and conversations with specialized therapists. The results should be interpreted in context — an auditory hypersensitivity score does not automatically indicate a pathology, but points towards specific adaptations and possibly an evaluation by an occupational therapist or a specialized psychomotor therapist.

Sensory sensitivity and autism (ASD): a fundamental and central link

Sensory peculiarities are so common and constitutive of the autistic experience that they were integrated into the official diagnostic criteria of the DSM-5 in 2013 — thus recognizing what autistic individuals and their families have long known. Criterion B4 of the DSM-5 describes: "Hyper- or hyporeactivity to sensory stimuli or unusual interest in sensory aspects of the environment." They are not a secondary or ancillary symptom — they are often at the heart of the daily experience of the autistic person, influencing their food choices, clothing preferences, environmental preferences, and social reactions.

Understanding sensory overload: crises and distress

Sensory overload (or sensory meltdown) occurs when sensory stimuli exceed the nervous system's capacity to integrate them. The supermarket with its flashing neon lights, multiple fresh product smells, crowded aisles, and loud background music can provoke a neural response in a hypersensitive autistic child equivalent to an extreme danger situation — with massive activation of the sympathetic nervous system, cortisol rise, behavioral disorganization, and sometimes a crisis that looks from the outside like an "anger outburst" but is actually a survival response to intolerable sensory overload.

Understanding that the crisis is not a tantrum or a behavioral choice but a neurological response to real and painful sensory overload changes everything in the approach to support. One cannot punish an overloaded nervous system — instead, one can reduce stimuli, create a safe retreat space, and gradually, over time and with the right tools, increase sensory tolerance.

The DYNSEO Alert Signals Map helps parents, teachers, and professionals identify precursor behaviors to sensory overload — before it reaches crisis point. Spotting early signals (increasing agitation, covering ears, withdrawing from contact, intensified stereotypical behaviors) allows for proactive intervention, at a time when regulation strategies are still accessible. The DYNSEO ASD Crisis Management Plan provides a structured intervention protocol for situations of intense overload — with clear steps that all stakeholders can apply consistently.

The Sensory Needs Map: personalizing support

The DYNSEO ASD Sensory Needs Map is a tool co-constructed with the child, their family, and professionals to precisely identify sources of sensory overload (stimuli to reduce or adapt in the environment) and preferred regulation strategies (soothing stimuli, calming rituals, safe spaces). This map can be shared with all stakeholders — teachers, speech therapists, specialized educators, doctors — to ensure consistency of adaptations across the child's different living environments.

Sensorial integration therapy: principles and evidence

Sensorial integration therapy, developed by neuropsychologist A. Jean Ayres in the 1960s-1970s and formalized in her foundational works ("Sensory Integration and the Child," 1979), aims to improve how the brain processes and organizes sensory information. It takes place in a specially equipped environment — sensory room with various types of swings, tunnels, trampolines, materials of varied textures, ball pits, inclined surfaces — which allows for graded and engaging sensory experiences.

The fundamental principle is that the therapist (occupational therapist or specialized psychomotor therapist) proposes sensory-motor activities tailored to the child's sensory profile — neither too stimulating (to avoid triggering overload) nor insufficient (to not miss the opportunity to train the system). The goal is to develop more flexible adaptive responses — not by forcing habituation to aversive stimuli, but by building a more robust sensory architecture through progressively enriched experiences.

Evidence and limitations

Sensorial integration therapy is the subject of debate in the scientific community regarding the robustness of its evidence base. Recent meta-analyses show significant positive effects on participation in daily activities, sensory tolerance, and certain aspects of overall functioning — but with variable effect sizes depending on studies and populations. The French HAS (Haute Autorité de Santé) recommends not offering sensorimotor integration therapy as an exclusive intervention, but incorporating it into a personalized comprehensive support plan. This nuance does not call into question the usefulness of the sensory approach — it invites rigorous and evaluated implementation.

Adapting the daily environment: a comprehensive practical guide for families

While waiting for or in addition to specialized therapeutic follow-up, families can implement environmental adaptations that significantly reduce sensory overload in daily life. These adaptations, based on the child's specific sensory profile, can transform daily crisis scenes into manageable situations.

At home: bedroom and living spaces

For children with auditory hypersensitivity: reduce background noise (television, continuous radio), use noise-canceling headphones during high-sound activities (vacuuming, cooking), choose textile floor coverings that absorb sound. For tactile hypersensitivities: choose clothing made from soft natural materials without tags and with flat seams (specialized brands available), wash new clothes before first use to soften fibers, create a "cozy space" with weighted blankets. For intense proprioceptive stimulation needs: provide a simplified "motor room" with a trampoline, an inflatable cushion, thick cushions for impacts — give legitimate alternatives to intense sensory seeking.

At the dining table

Restrictive eating is one of the most frequent and exhausting manifestations of sensory peculiarities in autism — and often the subject of misunderstandings "he is difficult," "he lacks good will." In reality, the refusal of certain foods is often linked to real gustatory, olfactory, or tactile hypersensitivities. The texture of a food (lumpy, stringy, slimy) can be perceived as deeply aversive — it is not a whimsical preference but a sensory reality. Gradual approaches (progressive exposure, food chaining) with the support of a speech therapist or an occupational therapist specialized in oral feeding often allow for gradual expansion of the diet.

At school

School is often the most challenging environment for children with sensory peculiarities — large room, intense and sometimes flashing artificial lights, constant background noise (multiple voices, chair noises, bells), unanticipated physical contact in the playground. Often simple adjustments can make a big difference: a noise-canceling headset allowed for individual work, a seat near a window for natural light, permission to discreetly get up for a few minutes of motor break, prior notification of schedule changes, a safe retreat space accessible during overload moments.

The MY DICTIONARY DYNSEO app allows non-verbal or minimally verbal children to express their level of sensory comfort and needs in the moment — without having to find words in a moment of overload that often deprives them of linguistic resources. For adapted cognitive activities, COCO offers exercises accessible to 5-10 year-olds in a predictable and stimulating interface without being overwhelming.

Sensory sensitivity in adults: late recognition and adaptations

Sensory peculiarities do not disappear in adulthood. Many adults have developed often unconscious compensation strategies — avoiding crowded restaurants, wearing earplugs on public transport, systematically choosing soft cotton clothing, working in quiet spaces, avoiding strong perfumes. These spontaneous adaptations are intelligent and legitimate — but they sometimes come with silent shame or misunderstanding from those around them who do not see the "reasons" for these seemingly rigid preferences.

Recognizing one's own sensory peculiarities in adulthood — often during a late ASD diagnosis, a journey of self-discovery, or the diagnostic process of a child revealing familiar traits — can be profoundly liberating. It gives meaning to experiences that seemed inexplicable, validates needs that were denied or minimized, and opens the way to intentional and accepted adaptations that significantly reduce chronic sensory fatigue. The Emotion Thermometer and the Choice Wheel DYNSEO are useful tools for adults learning to identify and manage their emotional and sensory state in daily life.

The diagnosis: when and how to consult

When sensory peculiarities are pronounced enough to significantly impact daily life — eating, sleeping, relationships, schooling — a professional evaluation is recommended. The DYNSEO Sensory Sensitivity Test can serve as an initial exploration and prepare for this consultation by identifying the most affected modalities.

In France, professionals specialized in the evaluation and support of sensory peculiarities are mainly occupational therapists (who use validated tools like the Sensory Processing Measure or the Short Sensory Profile), psychomotor therapists specialized in sensory integration, and neuropsychologists who incorporate these peculiarities into the overall cognitive functioning assessment. The medical reference remains the child psychiatrist or pediatric neurologist for the diagnosis of associated ASDs. The DYNSEO cognitive tests and DYNSEO training for professionals complete this evaluation and support ecosystem.

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