A child with SPD finds it difficult to process and act upon information received through the senses.

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Reprinted with permission from www.spdfoundation.net, Courtesy of Dr. Lucy Miller

Sensory processing (sometimes called "sensory integration" or SI) is a term that refers to the way the nervous system receives messages from the senses and turns them into appropriate motor and behavioral responses. Whether you are biting into a hamburger, riding a bicycle, or reading a book, your successful completion of the activity requires processing sensation or "sensory integration."

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.

Research by the SPD Foundation indicates that 1 in every 20 children experiences symptoms of Sensory Processing Disorder that are significant enough to affect their ability to participate fully in everyday life. Symptoms of SPD, like those of most disorders, occur within a broad spectrum of severity. While most of us have occasional difficulties processing sensory information, for children and adults with SPD, these difficulties are chronic, and they disrupt everyday life.

What SPD looks like

SPD can affect people in only one sense-for example, just touch or just sight or just movement-or in multiple senses. One person with SPD may over-respond to sensation and find clothing, physical contact, light, sound, food, or other sensory input to be unbearable. Another might under-respond and show little or no reaction to stimulation, even pain or extreme hot and cold. In children whose sensory processing of messages from the muscles and joints is impaired, posture and motor skills can be affected. These are the "floppy babies" who worry new parents and the kids who get called "klutz" and "spaz" on the playground. Still other children exhibit an appetite for sensation that is in perpetual overdrive. These kids often are misdiagnosed - and inappropriately medicated - for ADHD.

SPD is most commonly diagnosed in children, but people who reach adulthood without treatment also experience symptoms and continue to be affected by their inability to accurately and appropriately interpret sensory messages.

These "sensational adults" may have difficulty performing routines and activities involved in work, close relationships, and recreation. Because adults with SPD have struggled for most of their lives, they may also experience depression, underachievement, social isolation, and/or other secondary effects.

Sadly, misdiagnosis is common because many health care professionals are not trained to recognize sensory issues. The SPD Foundation is dedicated to researching these issues, educating the public and professionals about their symptoms and treatment, and advocating for those who live with Sensory Processing Disorder and sensory challenges associated with other conditions.

Learn more about the causes of SPD on the next page.