Sensory integration is an essential part of your development — it helps define everything from the way you see and hear things in the world, to the way that your body exists in space and more. Yet, research suggests that anywhere from 5% to 16.5% of people experience sensory processing challenges, especially in those with conditions like autism spectrum disorder.

Below, we’ll explore everything you need to know about sensory integration and sensory processing disorder, including how sensory integration therapy may help manage the symptoms of sensory challenges.

Sensory integration, also known as sensory processing, is the process by which the brain recognizes and responds to information our senses provide. So, this means how we process or integrate things that we see, taste, smell, touch, or hear — as well as the way that our body exists in space.

While there are eight senses that make up sensory processing, there are three systems in particular that are most affected by sensory disorders:

  • Tactile: Our tactile system processes information from the receptors in our skin, giving us a wide variety of “touch” sensations, such as pressure, temperature, and pain.
  • Proprioceptive: Our proprioceptive system involves our awareness of our own body through things like our muscles and joints, which tell our brains where we are in space.
  • Vestibular: Our vestibular system processes our movement and balance using an intricate set of organs inside the inner ear.

Research has shown that autism spectrum disorder (ASD) may change how people process sensory information. In fact, hyporeactivity and/or hyperreactivity to sensory input are one of the criteria for a diagnosis of ASD, according to The American Psychiatric Association’s Diagnostic and Statistical Manual, Fifth Edition (DSM-5).

One early meta-analysis of 14 different studies found a significant association between ASD and changes in sensory integration, including both hypersensitivity and hyposensitivity to sensory symptoms.

In another more recent study from 2020, researchers explored sensory symptoms in over 650 autistic adults using something called the Sensory Perception Quotient-Short (SPQ-Short) — a tool that can be used to measure sensory sensitivities. According to the study’s results, autistic adults are more likely to experience higher sensory sensitivity than neurotypical adults, especially females.

While some people do experience dysfunction in the way that they experience sensory input, sensory integration disorder isn’t actually a defined disorder in the DSM-5. In fact, the American Academy of Pediatrics specifically recommends against diagnosing sensory processing disorder and instead considering other underlying causes or conditions (such as ASD).

However, The Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood (DC:0-3) has a classification for sensory-related difficulties, as does the Interdisciplinary Council on Developmental and Learning Disorders (ICDL-DMIC). According to the ICDL-DMIC, the three types of sensory processing disorders include:

  • Sensory modulation challenges: These are characterized by a hyper-reactivity/hypo-reactivity to sensory input or sensory-seeking.
  • Sensory discrimination challenges: These can cause trouble identifying or distinguishing different types of sensory input.
  • Sensory-based motor challenges: These are characterized by difficulties moving or stabilizing the body and changes in muscle tone or tension.

When someone has sensory processing difficulties, their symptoms can vary depending on what type of sensory challenges they experience.

Sensory modulation challenges

Sensory modulation disorder is usually characterized by either an oversensitivity or undersensitivity to sensory input — or a craving for sensory experiences.

Oversensitivity

If someone experiences oversensitivity, they are more likely to become overwhelmed by typical sensory sensations. Symptoms of oversensitivity can look like:

  • hypersensitivity to certain sights, sounds, smells, or other senses
  • avoidance of strong sensory experiences
  • anxiety as a result of overstimulation from sensory input
  • sensitivity to specific tactile sensations (tactile defensiveness)
  • overreactions to bodily movements (gravitational insecurity)

Undersensitivity

If someone experiences undersensitivity to sensory input, they experience a delayed or reduced response to input. Symptoms of undersensitivity may look like:

  • decreased alertness and attention to sensory stimuli
  • increased threshold for tolerating sensations, such as pressure or pain
  • difficulty with movement, coordination, and even posture
  • differences in responses to social interactions (usually underresponsive to others)

Sensory-seeking

Sensory modulation challenges can also cause sensory-seeking, which is an increased need for sensory experiences. Sensory-seeking can cause symptoms such as a craving for different sensations (with a strong preference for certain sensations), trouble completing tasks, lower self-control, and even behavioral difficulties.

Sensory discrimination challenges

Sensory discrimination disorder is defined by difficulties interpreting different types of sensory inputs. Generally, this can cause a wide range of symptoms, depending on the type of sensory discrimination that is present:

  • visual discrimination disorder affects vision
  • auditory discrimination disorder affects hearing
  • tactile discrimination disorder affects touch
  • olfactory discrimination disorder affects smell
  • gustatory discrimination disorder affects taste
  • vestibular discrimination disorder affects body movement
  • proprioceptive discrimination disorder affects joints and muscles
  • interoceptive discrimination disorder affects internal sensations

Sensory-based motor challenges

Sensory-based motor disorders are characterized by sensory challenges that lead to changes in body posture and body movement. Usually, this can cause symptoms such as difficulties with body movements, fine motor skills, and routines that involve moving the body a certain way.

With sensory-based motor disorder, the symptoms differ depending on the subtype:

  • Postural dysfunction: This causes trouble stabilizing one’s body when moving or resting, leading to symptoms like lowered movement control, poor coordination, and difficulty with things like standing, sitting, bending, and opening joints.
  • Dyspraxia: This causes trouble with motor planning and execution, leading to increased trouble learning or carrying out new tasks and decreased fine motor skills, which often causes a person to appear more “clumsy.”

Sensory integration can be assessed using both observation from clinicians and assessment tools, such as those described below.

The Sensory and Integration Praxis Tests (SIPT)

The SIPT is a group of 17 tests that are considered the gold standard for diagnosing sensory processing conditions in children ages 4 to 8 years and 11 months. In addition to tactile, vestibular, and proprioceptive testing, the SIPT also includes tests related to praxis, coordination, perception, and more.

The Sensory Profile (SP)

The SP and SP2 tests for sensory processing issues using a two-pronged approach that test for sensory thresholds and behavioral responses. These two tests can help doctors determine what type of processing patterns someone may have, such as whether they’re sensory avoidant, sensory seeking, or something else.

The Sensory Processing Measure (SPM)

The SPM, which can be administered to both children ages 3 to 10 and preschoolers (SPM-P), is another tool used to evaluate sensory processing. However, this tool focuses not just on the standard sensory testing (tactile, vestibular, and proprioceptive) but also on social participation.

The Miller Assessment for Preschoolers (MAP)

The MAP is a shorter, easier alternative to the SIPT that can be used to assess sensory challenges in preschoolers. Like the SIPT, the MAP tests for tactile, vestibular, and proprioceptive challenges, as well as other learning delays that may be causing difficulties completing classroom tasks.

The Sensory Experience Questionnaire 3.0 (SEQ-3.0)

The SEQ-3.0 — as well as a similar test, the Sensory Sensitivity Questionnaire-Revised — can both be used to help identify any potential sensory challenges in children with ASD or other learning disabilities.

Ayres Sensory Integration (ASI) is one of the most well-researched treatment approaches for sensory integration challenges. Developed by Dr. A. Jean Ayres in 1989, ASI is a system that includes not only a theory of sensory integration but also tools to help diagnose and treat sensory processing disorders.

ASI, which is performed by trained occupational therapists (OTs), uses specific activities to help improve sensory integration by:

  • honing motor planning skills and sensory processing for affected senses
  • supporting the “organization of self” while encouraging body movement
  • creating focused activities, with specific equipment, to help improve behavior

ASI works best for preschoolers (ages 3 to 5) and middle schoolers (ages 6 to 11) to help improve social communication, cognition, academic ability, motor ability, and more. It can also be effective for adolescents ages 12 to 14, especially for social skills, behavior, and motor skills.

In some cases, adults may also benefit from tailored ASI treatments — especially in the areas of motor planning, social interactions, and self-development.

Early research on sensory processing challenges demonstrated potentially promising results for sensory integration therapy, especially in children.

For example, one early pilot study from 2013 found that individual sensory integration therapy was more effective than group therapy in improving sensory symptoms in autistic children with higher support needs.

However, research on the benefits of sensory integration therapy still remains limited, according to a recent review published in 2020. The authors report that while some studies have shown promising results for certain groups of people, more research is definitely needed in this area.

Still, for people with sensory challenges, sensory integration therapies may help improve not only symptoms but also the overall quality of life.

Sensory integration is part of development, helping to regulate input from your senses and perception of your orientation in space. Many individuals experience sensory integration challenges, especially people with conditions like autism spectrum disorder.

There’s some controversy around if sensory integration challenges are only a part of other disorders rather than an independent disorder. Nonetheless, there are occupational therapies that may help people who have sensory integration challenges.