Sensory Processing Disorder (SPD, formerly known as "sensory integration dysfunction") is a condition that exists when sensory signals don't get organized into appropriate responses. Pioneering occupational therapist and neuroscientist A. Jean Ayres, PhD, likened SPD to a neurological "traffic jam" that prevents certain parts of the brain from receiving the information needed to interpret sensory information correctly. A person with SPD finds it difficult to process and act upon information received through the senses, which creates challenges in performing countless everyday tasks. Motor clumsiness, behavioral problems, anxiety, depression, school failure, and other impacts may result if the disorder is not treated effectively.
Praxis is the ability by which we figure out how to use our hands and body in skilled tasks like playing with toys, using a pencil or fork, building a structure, straightening up a room, or engaging in many occupations. Practice ability includes knowing what to do as well as how to do it. Practice skill is one of the essential aptitudes that enables us "to do" in the world.
"Dys" means "difficult" or "disordered." Sensory integrative dysfunction may result in difficulty with visual perception tasks or in inefficiency in the interpretation of sensations from the body. For example-A dyspraxic child has difficulty using his or her body, including relating to some objects in the environment. A dyspraxic child often has trouble with simply organizing his or her own behavior.
These tests evaluate the ability to visually perceive and discriminate form and space without involving motor coordination. The Space Visualization is a puzzle-like test in which the child indicates which of two forms will fit a formboard. Although the child is invited to place the form in the hollow of the formboard, the motor aspect of the test does not enter into scoring the test. The examiner does keep track of whether the child used the right or left hand in picking up the blocks and, in doing so, whether he or she crossed the body's midline or tended to use each hand on its own side of the body. In the Figure-Ground Perception, the child points to pictures that are hidden among other pictures. The test measures how well a child visually perceives a figure against a confusing background.
These tests assess tactile, muscle, and joint perception. ("Soma" means "body.") During somatosensory testing the child is encouraged to "feel" rather than "see." A large piece of cardboard held over the area where the arms and hands are working helps the child concentrate on what is felt. Being touched where the child cannot see the touching often makes the child feel uncomfortable even though none of the tactile stimuli really hurt the child. If the child's negative reaction to the testing is strong, the response is referred to as "tactile defensiveness."
On the Manual Form Perception, the child identifies through the tactile and kinesthetic senses unusual shapes held in the hand. On the Kinesthesia, the conscious sense of joint position and movement is evaluated by the child's attempt to put his or her finger at the same place the therapist had previously put it. Tactile perception is measured with three tests:
(a) the Finger Identification, in which the child points to his or her finger that the therapist touched;
(b) the Graphesthesia, in which the child draws with a finger the same simple design the therapist drew on the back of the child's hand;
(c) the Localization of Tactile Stimuli, in which the child points to the spot where the therapist had lightly touched the child's arm or hand with a pen. This last test leaves 14 tiny, washable spots on the child's arm and hand.
Practice skill is evaluated six different ways:
(a) Praxis on Verbal Command assesses the ability to interpret verbally given instructions to assume certain positions and to then assume them. A typical test item might be "Put your hands on top of your head."
(b) Design Copying evaluates the ability to copy simple designs.
(c) Constructional Praxis evaluates the child's ability to build with blocks, using structures built by the therapist as models. Both the Design Copying and the Constructional Praxis require visual form and space perception, in addition to practice abilities.
(d) Postural Praxis requires the child to imitate the unusual body postures assumed by the therapist.
(e) Oral Praxis asks the child to imitate movements and positions of the tongue, lips, and jaw.
(f) Sequencing Praxis asks the child to imitate a series of simple arm and hand positions.
Four sensorimotor tests are included in the SIPT because their tasks require sensory integration. Bilateral Motor Coordination evaluates the ability to coordinate the two sides of the body in a series of arm movements. Standing and Walking Balance assesses the degree of sensory integration of the proprioceptive (muscle and joint) and vestibular (gravity and head movement) senses. On the Motor Accuracy, eye-hand coordination is measured by how well a child draws a line on top of a printed line. Executing the task requires eye muscle control, practice ability, visual perception, and motor coordination. Finally, the Postrotary Nystagmus measures the duration of the reflexive back and forth eye movements following rotation of the body (10 times in 20 seconds). This observation is one way of telling how well the nervous system is integrating the sensations from the vestibular system.
Once children with Sensory Processing Disorder have been accurately diagnosed, they benefit from a treatment program of occupational therapy (OT) with a sensory integration (SI) approach. Occupational therapy with a sensory integration approach typically takes place in a sensory-rich environment. During OT sessions, the therapist guides the child through fun activities that are subtly structured so the child is constantly challenged but always successful.
The goal of Occupational Therapy is to foster appropriate responses to sensation in an active, meaningful, and fun way so the child is able to behave in a more functional manner. Over time, the appropriate responses generalize to the environment beyond the clinic including home, school, and the larger community. Effective occupational therapy thus enables children with SPD to take part in the normal activities of childhood, such as playing with friends, enjoying school, eating, dressing, and sleeping.
Ideally, occupational therapy for SPD is family-centered. Parents are involved and work with the therapist to learn more about their child's sensory challenges and methods for engaging in therapeutic activities (sometimes called a "sensory diet)" at home and elsewhere.
Treatment for Sensory Processing Disorder helps parents and others who live and work with sensational children to understand that Sensory Processing Disorder is real, even though it is "hidden." With this assurance, they become better advocates for their child at school and within the community.