OVERVIEW

What is sensory integration in sensory integration dysfunction?

Sensory integration (SI) refers to the brain's ability to organize, analyze, and synthesize sensory information received from various sensory systems—such as vision, hearing, smell, touch, vestibular (balance), and proprioception (body awareness)—to make appropriate decisions, enabling the body to function harmoniously and effectively.

The "sensory integration theory" is a hypothesis proposed by Dr. Anna Jean Ayres in the 1970s during her treatment of children with cerebral palsy. Later, it gained attention and support among some rehabilitation therapists in the U.S., who believed that insufficient or inappropriate sensory development could be considered a disorder and could be improved through proper treatment.

What is sensory integration dysfunction?

Sensory integration dysfunction (SID) is a diagnosis derived from the "sensory integration theory." It refers to the brain's inability to effectively process sensory information, leading to a range of behavioral issues in children, manifesting as developmental and behavioral abnormalities in areas such as learning, concentration, posture control, fine motor coordination, emotions, social interactions, and self-care abilities, ultimately affecting the child's quality of life and learning capacity.

However, the American Academy of Pediatrics states that there is currently insufficient convincing evidence to prove that sensory integration deficits are the cause of related dysfunctions and does not recommend it as a standalone diagnosis. Below, we will also describe "sensory integration dysfunction" as a clinical phenomenon.

Is sensory integration dysfunction common?

It is estimated that the prevalence of sensory integration dysfunction is around 10% in the general population, while it rises to as high as 30% in children with developmental disorders.

Are sensory integration dysfunction and developmental coordination disorder the same condition?

They overlap but are not identical.

Developmental coordination disorder (DCD) refers to impaired ability in children to execute and learn age-appropriate motor skills—including fine and gross motor skills, balance, and daily activities—without any known medical or neurological conditions.

It primarily manifests as clumsiness, poor coordination, and significantly slower motor skill acquisition compared to peers, and this impairment affects daily functional activities and academic performance.

Some scholars believe that sensory integration dysfunction is one of the causes of developmental coordination disorder, where poorly integrated vestibular, proprioceptive, and tactile information leads to uncoordinated movements and insufficient motor skills.

SYMPTOMS

What are the common manifestations of sensory integration dysfunction?

SID primarily manifests as learning difficulties and social interaction challenges. Based on the relationship between sensory stimuli and SID, the main manifestations include:

• Vestibular balance disorder:
  • Hyperactivity, difficulty concentrating, poor coordination, weak balance, clumsiness, frequent falls, confusion between left and right, disorientation, reversed strokes or radicals in writing, inconsistent character sizes, and poor alignment.
  • Difficulty visually tracking moving objects or shifting focus smoothly. Eye movements may be unsteady, often jumping to locate new targets, leading to skipping words or lines while reading, reading difficulties, and calculation errors. These issues result in learning difficulties (not due to intellectual factors).
  • Poor vestibular sensation can impair visual-spatial judgment, making it hard to assess distances and directions. Some children show delayed reactions to heights, leading to excessive climbing without fear, while others are overly sensitive and afraid of any height.
  • Head position changes may cause tension, leading to fidgeting or self-talk to alleviate anxiety, which is one reason why children with poor balance tend to be hyperactive and talkative.
• Proprioceptive dysfunction:
  • Difficulty learning skills like tying shoelaces, riding a bike, jumping rope, or rolling. Prone to motion sickness and dizziness during vigorous movement.
• Tactile dysfunction:
  • Children with tactile defensiveness overreact to environmental changes, respond hastily to stimuli, and have restless minds, making it hard to focus or process learning information into the cerebral cortex. They may exhibit poor social skills, shyness, anxiety, irritability, aggression, picky eating, and possessiveness.
  • Children with underresponsive tactile systems often lack self-awareness, display poor motor skills, and show low motivation for learning.
• Auditory dysfunction:
  • Proper integration of auditory information is essential for language development in infants and toddlers. Poor auditory processing can lead to delayed language development.
  • Children with auditory integration issues may also appear impatient, struggle to focus, and have difficulty distinguishing sound sources or filtering out background noise, making it hard to grasp learning content.

Which systems are related to sensory integration dysfunction?

It is associated with various sensory systems, such as vision, hearing, smell, touch, vestibular (balance), and proprioception (body awareness).

How does sensory integration dysfunction develop?

Sensory integration dysfunction may initially go unnoticed by parents but gradually progresses over time. Without active guidance or intervention, it may persist into adulthood.

What severe consequences can sensory integration dysfunction cause?

Sensory integration abilities may impact cognitive function, emotional development, learning, adaptability, and behavior, thereby limiting a child's overall development.

CAUSES

What are the common causes of sensory integration dysfunction?

The exact cause of sensory integration dysfunction remains unclear.

Possible factors include genetic predisposition, prenatal exposure to harmful substances (such as smoking, alcohol, or certain medications), premature birth, perinatal complications (e.g., asphyxia, infections), postnatal exposure to environmental toxins, parenting styles and environment, and parental characteristics (e.g., personality traits, physical constitution).

The most likely cause is innate individual differences in sensory information processing and susceptibility to environmental factors.

Who is more prone to sensory integration dysfunction?

It commonly occurs in children with developmental disorders, such as cerebral palsy, autism spectrum disorder (ASD), attention deficit/hyperactivity disorder (ADHD), and developmental coordination disorder, where the incidence of SID is higher.

Is sensory integration dysfunction hereditary?

If SID is caused by conditions like ASD, ADHD, or developmental coordination disorder, there may be a genetic correlation. For SID in the general population, acquired factors likely play a more significant role.

DIAGNOSIS

How is Sensory Integration Dysfunction Diagnosed?

The identification and assessment of sensory integration dysfunction typically involve the Sensory Integration Evaluation Scale developed in 1989, which evaluates children's coordination functions such as tactile perception, vestibular-proprioceptive sense, spatial perception, and vision. In recent years, new sensory assessment scales have been developed, including the Sensory Integration Assessment Scale, Infant and Toddler Sensory Assessment Scale, and Adult Sensory Assessment Scale.

The American Academy of Pediatrics does not recommend diagnosing sensory integration dysfunction as an independent condition. When these sensory symptoms appear, possible risks of other developmental disorders—especially Autism Spectrum Disorder (ASD), Attention Deficit/Hyperactivity Disorder (ADHD), and Developmental Coordination Disorder (DCD)—must be considered.

What Tests Are Needed for Sensory Integration Dysfunction?

Generally, diagnosis can be made through medical history, symptoms, physical examination, and related scales, with no need for laboratory or imaging tests. If conditions like ASD, ADHD, or DCD are suspected, relevant assessment scales may be used, requiring referral to specialists such as developmental-behavioral pediatricians or pediatric neurologists.

• If motor coordination issues are present, vision and fundus examinations may be needed to determine whether they are related to visual impairment or neurological conditions.
• Children with auditory integration difficulties should undergo hearing assessments by an ENT specialist.
• If neurological abnormalities are found and focal brain lesions are suspected, an MRI may be required.
• For children with low muscle mass or physical limitations, tests like lactate dehydrogenase, creatine kinase, and thyroid function may be conducted to assess neuromuscular or thyroid disorders.
• If clumsiness worsens, additional tests may be performed based on clinical suspicion—e.g., MRI for brain tumors or hydrocephalus, biochemical or genetic tests for metabolic disorders like aminoaciduria or Wilson’s disease, or electromyography for neuromuscular diseases.
• For children with suspected ASD or ADHD, blood lead levels and thyroid function tests may be recommended to rule out contributing factors.

What Should Be Noted During a Visit for Sensory Integration Dysfunction?

Medical history, symptoms, physical examination, and related scales are usually assessed by the doctor through direct observation of the child and parental interviews. The primary caregiver's responses are crucial for accurate clinical judgment.

Which Conditions Are Easily Confused with Sensory Integration Dysfunction? How to Differentiate?

As mentioned earlier, sensory integration dysfunction should not be diagnosed in isolation. Other developmental disorders—particularly ASD, ADHD, and DCD—must be considered.

• Children with ASD often exhibit social difficulties and repetitive behaviors.
• ADHD primarily manifests as inattention, hyperactivity, and impulsivity across settings.
• DCD is characterized by motor skill deficits, including poor coordination, balance, and daily activities, without intellectual or social impairments. Currently, sensory integration dysfunction is considered one potential cause of DCD, with some overlap between the two.

TREATMENT

Which department should I visit for sensory integration disorder?

For initial screening, you can go to the Child Health Department or Pediatrics Department (look for pediatricians with child health experience). If further diagnosis or treatment guidance is needed, a referral to a developmental behavioral pediatrician, pediatric neurologist, child psychiatrist, or child psychologist may be considered.

Can sensory integration disorder improve on its own?

Not necessarily.

For typical children, symptoms may alleviate naturally through daily practice and environmental influences, while some children may retain lifelong issues.

If sensory integration disorder is caused by conditions like autism spectrum disorder (ASD), attention deficit/hyperactivity disorder (ADHD), developmental coordination disorder (DCD), or cerebral palsy, it generally does not improve on its own and may worsen with age.

How is sensory integration disorder treated?

Treatment involves sensory-motor activities that enhance tactile, vestibular, proprioceptive, and visual stimulation.

• Activities like swinging, hanging, spinning, trampolining, sliding, crawling through tunnels stimulate the vestibular system.
• Light brushing, joint compression, or body pressure with cushions stimulate tactile and proprioceptive systems.
• Assembling objects, drawing, or navigating mazes can improve visual-motor and hand-eye coordination.

Therapists monitor children’s responses and adjust training plans accordingly. They also collaborate with parents and teachers to help children adapt to daily life and provide "sensory-motor prescriptions" for home and school.

Medication is unnecessary unless a specialist determines the disorder is linked to ADHD or another condition requiring drug treatment.

What are common training tools (toys) for sensory integration disorder?

Common tools include swings, hanging ropes, spinning equipment, trampolines, slides, balance boards, tunnels, therapy balls, brushes, puzzles, mazes, etc.

Is sensory integration therapy effective?

The effectiveness is debated. Some studies suggest benefits, while others show no effect. However, these studies lack rigorous randomized controlled designs, so evidence is inconclusive.

Can sensory integration disorder be completely cured?

Current research lacks sufficient evidence. If the sensory integration hypothesis holds, training may theoretically help. Some children show improvement after therapy, but outcomes vary.

DIET & LIFESTYLE

What should patients with sensory integration dysfunction pay attention to in their diet?

Pay attention to a reasonable diet and ensure nutrition. Eat foods rich in DHA, such as fish, shrimp, shellfish, eggs, etc.

What should patients with sensory integration dysfunction pay attention to in daily life?

Face your shortcomings correctly, participate in relevant exercises to improve, actively engage in social activities, and enhance self-confidence and self-esteem.

Does sensory integration dysfunction require follow-up? How to follow up?

Regularly visit developmental behavioral pediatricians, pediatric neurologists, child psychiatrists, or child psychologists/therapists to track changes in the condition and develop the next training plan.

Does sensory integration dysfunction affect fertility?

No.

What should caregivers of patients with sensory integration dysfunction pay attention to?

Avoid mocking or scolding, and never use punishment as a "training" method for sensory integration dysfunction, as this may worsen symptoms or even cause psychological problems. Provide positive guidance, proactive care, communication, encouragement, companionship, and reassurance. Parents should spend more quality time with their children and guide their abilities through various parent-child games.

PREVENTION

Can Sensory Integration Dysfunction Be Prevented? How to Prevent It?

The exact pathogenesis of sensory integration dysfunction remains unclear. Recent domestic and international studies suggest that the causes may involve a combination of biological, psychological, and social factors. The following measures can help reduce the likelihood of sensory integration dysfunction:

• Maintain prenatal health and ensure balanced nutrition during pregnancy;
• Avoid smoking, alcohol, and medications that may affect the fetus;
• Stay emotionally relaxed and avoid excessive fatigue or negative emotions;
• Prevent viral infections during pregnancy;
• Follow proper prenatal and child healthcare to minimize neonatal brain injuries (e.g., premature birth, asphyxia) and severe jaundice. Avoid viral or bacterial infections during infancy;
• Promote family harmony, provide ample parent-child bonding, care attentively, and engage in emotional communication with the child. Avoid inappropriate parenting methods (e.g., overprotection, restricting the child's activity space or social interactions, harsh scolding, corporal punishment, or emotional neglect);
• Additionally, take precautions to prevent chronic lead poisoning.