Sensory Processing Disorders (SPD)
SPD is a brain disorder that impacts the ability to organize sensory stimuli such as movement or touch. It is also called "Sensory Modulation Disorder " because children have difficulties interpreting and responding to sensations. For example, they might overreact with distress when touched or underreact-appearing slugglish during a gym class. Symptoms can vary. Babies with SPD may cry more than normal and demonstrate difficulties with sleeping and feeding. Some children crave fast movement, whereas others fear having their feet off the ground. In addition, many children with SPD appear to be clumsy, struggle with hand writing and demonstrate attention and visual-perceptual difficulties that impact reading skills. Children with autism frequently present with several of these symptoms.
How Does It Work?
Occupational therapy sensory diets are typcially designed to stimulate the vestibular, proprioceptive and tactile sensory systems. These sensory systems lay the foundation for interacting with the environment and learning. The vestibular system, also called the “balance system", is made up of sense organs located in the inner ear that detect the pull of gravity and movement of the head. The proprioceptive sensory receptors are in the muscles and joints. They tell the brain where the body parts are and how they are moving. The term “tactile" refers to touch and the skin is our tactile sensory organ.
This system enables the child to locate where she was touched and identify what an object is without using vision. Children need to interpret touch and movement and understand where their bodies are in space and in relation to objects before they can learn how to manipulate objects such as pencils, scissors or buttons. Sensory diets help children feel more comfortable with sensations that they interpret as aversive such as touch to the palm and in turn, engage in functional tasks such as painting.
Creating a Sensory Diet
Students with SPD may be over or under-reactive to stimuli. For example, an over-aroused student who is highly distractible, anxious and hyperactive may benefit from quiet music, squeezing objects, darkened lights and the deep pressure provided by a bean bag chair or weighted vest. This child might respond well to the proprioceptive and vestibular stimulation provided by jumping off a swing and crashing into a mountain of pillows.
A student with an under-reactive sensory system may appear to be lethargic and benefit from erratic movement, fast music, chewing gum, fidget toys and bright lights.
An occupational therapist (OT) can help teachers create a “sensory diet" that meets the individual needs of a child with SPD. This diet often includes movement activities throughout the day (i.e. scooter board, swing, slides or jumping jacks), deep pressure/proprioceptive activities (i.e. squeezing a glue bottle), wearing headphones with quiet music or looking at pictures in a darkened, quiet corner.
Occupational therapy sensory diets help children with sensory processing disorders interpret the environment more accurately so that they don't fear a pat on the shoulder or falling off a step. A sensory diet should be provided with a predictible schedule, preferably a visual schedule that the student can follow. This helps the student feel emotionally safe their often unpredictible and confusing world. Although sensory activities may look like fun, they are often essentia for the student with a sensory processing disorder to succeed in school.
“Building Bridges through Sensory Integration"; Ellen Yack, Paula Aquilla & Shirley Sutton; 2004.
“How Does Your Engine Run?"; Mary Sue Williams and Sherry Shellenberger; 1994.
“Sensory Integration and the Child"; A. Jean Ayres; 2005.
“Autism: A comprehensive Occupational Therapy Approach"; Heather Miller Kuhaneck & Renee Watling; 2010.