In Support of Sensory Integration
Dr. Anna Jean Ayres coined the term "sensory integration dysfunction" in the 1960's, but sensory integration (SI) treatment has only recently gained attention in the medical field. Research in this area is still in its infancy and substantial work is needed before enough thorough empirical data are available to reach valid conclusions about the effectiveness of this type of intervention. I believe that one of the reasons that the current research does not consistently reflect the efficacy of SI because each child with sensory processing differences is so unique and improvements can be challenging to capture. Also, effectiveness studies administered in natural settings such as a therapy clinic (as contrasted with laboratory settings) are complex and must deal with multiple potential confounds (SPD Foundation, 2004). Well-trained and experienced OTs know that the same SI treatment that works for one child with sensory defensiveness may not work for another child with sensory defensiveness. It is the nature of our jobs to figure out the best approach to use for each child and therefore a strict, regimented protocol (as used in research studies) will not necessarily be the most appropriate mode of treatment for all children with like diagnoses. Skilled OTs know how to adapt the SI intervention to meet the child's unique and fluctuating sensory system. Effective intervention not only includes skilled OT (and SLP and PT!) services but also follow-through in the home and school environments, as well.
Some researchers question whether a child's over- or under-responsivity to sensory stimuli may have a behavioral component, rather than a neurological basis. However, current research does suggest children with sensory processing disorder have differences in the way the brain makes sense of sensory input. Recent studies of electrodermal reactivity during a sensory challenge protocol found that children with severe sensory processing dysfunction differ significantly in the reactivity of their sympathetic nervous systems when compared to typically developing children after sensory stimulation (SPD Foundation, 2003). This suggests that children with autism and other diagnoses may in fact have differences in their brain pathways for processing sensory information, and that their reaction to sensory stimulation is not purely a behavior response.
Some people only think of sight, taste, touch and sound as components of the sensory system – leaving out the vestibular and proprioceptive systems completely. These two "hidden" systems typically lay the groundwork for the functioning of the other sensory systems and play a large part in maintaining regulation for participation in daily tasks. It is difficult for children with sensory processing differences to form appropriate responses to visual, gustatory, tactile, and auditory input before first understanding their body's position in space and in relation to other objects and people.
However beneficial SI may be, it is important not to use SI intervention as a standalone treatment. OTs are trained to look at the child's whole system – cognitive, behavioral, motor, social, etc – and we would not be doing our job if we were addressing the sensory system in isolation. In an ideal world, all OTs would team with each child's pediatricians and other therapists to create an environment where each professional is bringing their specialty to the child's treatment, making it so that all possible diagnoses are being discussed and considered. I am in favor of making SPD an official diagnosis so that healthcare professionals have clear criteria from which to diagnose, refer, and treat.
Research in SI intervention has only recently begun and has a long way to go. It is crucial to promote further research in SI rather than dismiss it as being an unproven therapeutic intervention. I believe that research which examines children with sensory processing differences on a case-by-case basis will reflect what I see at ICAN Center for Autism every day: the amazing progress that children make in their daily functioning with the proper sensory supports in place. I would like to close my thoughts with a quote from an anonymous OT from New York:
"I have seen children who were terrified to be touched and/or would scream if their bodies came into contact with some sort of tactile input make great gains, being able to play with peers and get messy doing typical kid things. I have so many other examples, too many to name. But when you talk about lack of research, you have to remember that kids with special needs need many different services, working together, to produce great improvement. As a parent, I would not consent to having my child participate in only one type of therapy to test its success. As a therapist, it seems unethical. The best thing is for sensory therapy - if indicated - to be part of an effective treatment team."
Posted by: Erica, Occupational Therapist