Sensory Integration: History and Theory
Sensory integration is a specialty area of occupational therapy that is based on over 40 years of theory and research. The term “sensory integration” refers to:
- The way the brain organizes sensations for engagement in occupation
- A theory based on neuroscience that provides perspective for appreciating the sensory dimensions of human behavior
- A model for understanding the way in which sensation affects development
- Assessments including standardized testing, systematic observation, and parent or teacher interviews that identify patterns of sensory integration dysfunction
- Intervention strategies that enhance information processing, praxis, and engagement in daily life for individuals, populations and organizations
History of Sensory Integration
The sensory integration (SI) specialty was originally developed by A. Jean Ayres PhD, OTR, who was both an occupational therapist and an educational psychologist. A former member of the USC occupational therapy faculty, she developed a theoretical framework, a set of standardized tests (today known as the Sensory Integration and Praxis Tests), and a clinical approach for identification and remediation of SI problems in children. Her publications on sensory integration span a 30-year period from the 1960s through the 1980s, and include psychometric studies as well as clinical trials and single case studies.
What Does SI-Based Occupational Therapy Look Like?
Most SI research and practice focuses on children who have a variety of developmental and learning difficulties, including autism and other developmental disabilities, developmental risk conditions, behavior and attention disorders, learning disabilities and developmental coordination disorder. Thorough assessment is critical in ascertaining whether a sensory processing issue is a factor in the child’s development, and if so, which intervention strategies will best help the child and family. Classic intervention usually takes place within a specially designed therapeutic environment that allows the therapist to present specific sensory and movement challenges to the child, which gradually increase in complexity over time. This kind of intervention is characterized by a playful atmosphere in which the child is encouraged to generate ideas for activities, to flexibly respond to novel challenges and to develop confidence as well as competence. Intervention includes consultation and education with parents, teachers and other caregivers, modification of environments and inclusion of appropriate sensory-based activities throughout the day. The application of sensory integration principles within organizations takes into consideration the sensory demands in the workplace. The application for populations takes into account the sensory and practic differences and demands for a population such as adults with autism.
More About Sensory Integration
The term sensory integration holds special meaning for occupational therapists. In some contexts it is used to refer to a particular way of viewing the neural organization of sensory information for functional behavior. In other situations this term refers to a clinical frame of reference for the assessment and treatment of persons who have functional disorders in sensory processing. Both of these meanings originated in the work of A. Jean Ayres, an occupational therapist and educational psychologist whose brilliant clinical insights and original research revolutionized occupational therapy practice with children. Ayres’ ideas ushered in a new way of looking at children and understanding many of the developmental, learning and emotional problems that arise during childhood.
Sensory Integration in Child Development
One of the most distinctive contributions that Ayres made to understanding child development was her focus on sensory processing, particularly with respect to the proximal senses (vestibular, tactile and proprioceptive). From the sensory integration viewpoint, these senses are emphasized because they are primitive and primary; they dominate the child’s interactions with the world early in life. The distal senses of vision and hearing are critical and become increasingly more dominant as the child matures. Ayres believed, however, that the body-centered senses are a foundation on which complex occupations are scaffolded. Furthermore, when Ayres began her work, the vestibular, tactile and proprioceptive senses were virtually ignored by scholars and clinicians who were interested in child development. She devoted her career to studying the roles that these forgotten senses play in development and in the genesis of developmental problems of children. A basic assumption made by Ayres was that brain function is a critical factor in human behavior. She reasoned, therefore, that knowledge of brain function and dysfunction would give her insight into child development and would help her understand the developmental problems of children. However, Ayres also had a pragmatic orientation that sprang from her professional background as an occupational therapist. She was concerned particularly with how brain functions affected the child’s ability to participate successfully in daily occupations. Consequently, her work represents a fusion of neurobiologic insights with the practical, everyday concerns of human beings, particularly children and their families.
As Ayres developed her ideas about sensory integration, she used terms such as sensory integration, adaptive response and praxis in ways that reflected her orientation. She drew other terms from the literature of other fields. When Ayres borrowed a term from another field, however, she imparted a particular meaning to it. For example, Ayres did not use the term sensory integration to refer solely to intricate synaptic connections within the brain, as neuroscientists typically do. Rather, she applied it to neural processes as they relate to functional behavior. Hence her definition of sensory integration is the “organization of sensation for use.” It is the inclusion of the final clause “for use” that is a hallmark of Ayres because it ties sensory processing to the person’s occupation.
Ayres introduced a new vocabulary of sensory integration theory and synthesized important concepts from the neurobiological literature to organize her views of child development and dysfunction. Many of these ideas were first published in her classic book, Sensory Integration and Learning Disorders (1972). Later she wrote a book for parents, Sensory Integration and the Child (1979, 2004), outlining the behavioral changes that can be observed in a child as sensory integration develops.