The sensory integration intervention approach is one of several treatment methods provided by
occupational therapists for individuals with autism spectrum disorders (ASD). Its initial
development can be traced to a systematic research program launched by A. Jean Ayres, PhD,
who was both an occupational therapist and an educational psychologist. Following her
NIH-sponsored training at the UCLA Brain Research Institute and the Division of Child
Development from 1964-1966, Dr. Ayres developed the sensory integration intervention
approach based on scientific studies of the effects of environmental enrichment (including
multisensory stimulation) in promoting brain neuroplasticity. During her subsequent tenure as a
faculty member in the Department of Occupational Therapy at the University of Southern
California, she further specified the theoretical framework that undergirds sensory integration,
constructed a set of standardized tests (today known as the Sensory Integration and Praxis Tests),
and refined the clinical approach for identification and remediation of sensory
integration/processing problems in children, including those with ASD. Ayres’ numerous
publications span more than 30 years (from the 1960s through the 1980s), and include
psychometric studies, outcome studies, and single case studies. Since Dr. Ayres’ death in 1988,
occupational therapists have continued to advance sensory integration research and practice,
modified in accord with current neuroscience findings. Today’s use of sensory integration
procedures by licensed occupational therapy professionals typically takes place in private clinics,
schools, and not-for-profit therapy facilities.
Sensory integration refers to the organization of multisensory input for perception, which is
requisite for functional behavior. One can think of the various sensations we experience (touch,
sight, smell, hearing, movement/motion, and proprioception) as needing to come together to
form images of the world that guide our actions. For example, linking vision and pressure on
your feet enables you to walk down stairs or feel you are about to trip on a sidewalk slab. Ayres’
theory of sensory integration postulates that the ability to properly process and integrate sensory
input provides a critical foundation for adaptive behavior and learning. According to this view,
integration and organization of information from all the sensory systems is foundational for the
performance of complex behaviors such as coordinated eye movements, postural adaptation and
motor skills, and speech and language, and also facilitates higher-order outcomes such as
academic learning ability, self-control, and self-esteem.
Intervention approaches employed by occupational therapists for children with ASD can be
broadly classified into those which are performance-oriented/skill-based (e.g., Cognition
Orientation to (Daily) Occupational Performance or CO-OP) and those which are sensory-based
(e.g., the sensory integration intervention approach). Research has suggested that nearly 95% of
individuals with ASD have sensory abnormalities that may interfere with the ability to attend to
tasks, perform coordinated motor actions, plan and sequence activities, develop social
relationships, manage classroom demands, perform self-care tasks, or participate in family
activities. Sensory abnormalities frequently present as over- or under-responsivity to touch,
movement, sights, and sounds, and/or poorly coordinated movement. The American
Occupational Therapy Association (AOTA) recognizes the sensory integration intervention
approach as one of many treatment methods used by occupational therapists working with
children with ASD. When employing the sensory integration intervention approach, the trained
clinician must evaluate the child’s sensory processing to identify strengths and deficits, as well as
the impact of such deficits on everyday functioning, as a means of informing the development of
an appropriately tailored intervention program.
In general, sensory integration deficits commonly experienced by individuals with ASD can be
divided into two overarching categories, as briefly described below.
Atypical Sensory Modulation
Children with ASD are often hyper- or hypo-responsive to sensory stimuli. In the case of
hyper-responsivity, the child may overreact to seemingly benign input such as a light touching of
the skin, perceiving it as irritating or even painful. In contrast, a child with hypo-responsivity
may be oblivious to naturally occurring sensory input in the environment and seek out forms of
intense stimulation. Ayres proposed that these modulation concerns could be addressed through
the provision of appropriate, finely gradated, and carefully monitored sensory experiences.
Atypical Sensorimotor Integration
This category can be further broken down into two subcategories:
Poor Postural, Ocular and Bilateral Integration
Children with ASD who have problems with postural, ocular, or bilateral integration may appear
clumsy, have difficulty moving the eyes accurately from one spot to another, experience poor
eye-hand coordination, or have difficulty with gross and fine motor activities that require the
coordination of two hands, such as riding a bike or cutting with scissors. These difficulties are
hypothesized to stem from inadequate neural integration of vestibular and visual stimuli and
proprioceptive input from the muscles and joints. Ayres proposed that a sensory integration
intervention approach focused on facilitating postural mechanisms through the use of graded
vestibular stimuli will enable enhanced nervous system function and facilitate improved postural
responses, overall core strength, ocular motor control, and bilateral integration.
Developmental Dyspraxia
Praxis is defined as the ability to plan motor activities in space and time. Its execution relies on
the brain’s neuronal map-making abilities which construct body and environmental schemata
through multi-sensory experiences. These schemata may be referred to as body schemes, body
images, or, in relation to the environment and the objects within it, spatial maps. Together, these
substrates depict the spatial relationships between the body and the objects encountered in the
environment. The child with ASD who has poor body and environmental schemata can be
described as having developmental dyspraxia, and may be unable to accurately develop skilled
use of objects and plan successful motor sequences to novel environmental challenges. Both
motor planning and motor skills require a perception of how the body is designed and functions
as a whole, and poor body and environmental schemata limit the complexity of plans that can be
generated in response to novel motor tasks. Ayres proposed that a sensory integration
intervention approach in which tactile, proprioceptive, vestibular, and visual stimuli are provided
through progressively more challenging environmental demands will improve body and
environmental schemata and facilitate the development of praxis.
Although numerous studies have been published on the effectiveness of a sensory integration
intervention approach with other populations, a rapidly cumulating body of evidence now
supports the use of a sensory integration approach for treating children with ASD. In this vein,
research suggests that sensory integration or sensory integration-related interventions can
decrease ASD symptoms. This positive record of evidence extends to single subject design
studies (e.g., Case-Smith & Bryan, 1999; Linderman & Stewart, 1999), small-scale randomized
controlled trials (Fazlioglu & Baran, 2008; Pfeiffer et al., 2011; Schaaf, under review) and at
least one within-subjects experimental investigation (Smith et al., 2005). In the randomized trial
conducted by Pfeiffer et al. (2011), for example, 37 children with ASD (6-12 years of age) were
randomly assigned to either a six-week SI intervention or a fine motor intervention; the results
indicated that the children who received SI demonstrated greater improvements in individualized
goal attainments in functional skills, and a decrease in autistic mannerisms.
Based on an assessment across studies, the sensory integration intervention approach as
described is recommended to be delivered three times per week in one-hour sessions for a
minimum of three months, at which time a determination can be made as to whether continued
therapy would be beneficial. In addition to the 1:1 intervention as described above, the therapist
also provides individualized training to parents and teachers to assist them in utilizing sensory
strategies throughout the child’s day to support development of sensory processing abilities and
enhance functional performance and participation. Specific suggestions may also be provided to
assist parents and teachers in modifying the physical environment to meet the child’s unique
sensory processing needs
Evidence-Based research on Occupational Therapy:
Effectiveness of sensory integration interventions in children with autism spectrum disorders: A pilot study. 1 (subscription needed)Some children with ASD may have sensory processing disorder (SPD), where they have difficulty regulating responses to external stimuli and sensations. They may use self-stimulation to compensate or choose to avoid overstimulation. According to this article, sensory integration (SI) treatment involves “meaningful therapeutic activities characterized by enhanced sensation, especially tactile, vestibular, and proprioceptive, active participation, and adaptive interaction.” This article reports on a randomized controlled trial comparing an SI intervention to an intervention focused on fine motor skills. The study was designed as a pilot to establish a model for future research.
In this pilot study, 37 children with ASD between the ages of 6 and 12 were randomized to either sensory integration or fine motor (FM) intervention during a summer activities program. All researchers and parents were blinded to group assignment. During each SI session, an occupational therapist “engineered the characteristics of the environment to create a just-right challenge” based on the child’s needs assessed during baseline evaluation. In contrast, the FM intervention included construction, drawing, writing, and crafts, all focusing on fine motor skills. At the end of the six week program, the SI group showed fewer autistic mannerisms and more improvement in attainment of goals as rated by teachers and parents. Those goals focused on sensory processing, motor skills, and social function.
1 Pfeiffer, B. A., Koenig, K., Kinnealey, M., Sheppard, M., & Henderson, L. (2011). Research Scholars Initiative—Effectiveness of sensory integration interventions in children with autism spectrum disorders: A pilot study. American Journal of Occupational Therapy, 65, 76–85. doi: 10.5014/ajot.2011.09205