What Is Sensory Processing Disorder?
Sensory Processing Disorder (SPD) is a neurodevelopmental disorder resulting from the brain’s inability to integrate everyday sensory information received from the five senses: touch, vision, sound, smell, and taste.
In addition to the commonly known five senses are two additional senses that are rarely heard of: the vestibular and proprioceptive systems. The vestibular system has functions located in the base of the brain (cerebellum), the upper part of the neck (cervical spine) and the inner ear. It is the “chief regulator” of all incoming sensory information and is considered the most important sensory system. The proprioceptive system is located throughout the spine as well as all other joints of the body. Dysfunction within the sensory integration system can lead to problems with learning, motor skills, behavior, and social and emotional development. It is estimated that as many as 1 in 20 children suffer from SPD.
Some children with SPD are hypersensitive: they feel bombarded by sensory information. These children may appear to be withdrawn socially because they avoid activities that make their brain feel “uncomfortable.” On the other hand, children who are hyposensitive to sensory information may seek out intense sensory experiences in order to “feed” their brain. Complicating the diagnostic process are children who may have a mix of hypersensitive and hyposensitive sensory systems.
Some signs children may exhibit with Sensory Processing Disorder:
Touch: Children who have difficulties processing tactile sensory input may appear: anxious, controlling, or aggressive. They may avoid or crave touch, dislike messy play such as finger painting, appear irritated by certain clothing (e.g. tags in shirts) or food textures, appear irritated when someone is in close proximity, often are very active or fidgety, have difficulty manipulating small objects, use their hands to explore objects, or often put objects in their mouth.
Smell: These children may be susceptible to allergies, especially environmental allergies. They may exhibit an excessive need to smell toys, items, or people or they may not like new cloths, toys, or furniture because of the smell. Their behavior or health may deteriorate after cleaning house due to the toxic effect of the cleaning chemicals.
Taste: Children who have trouble processing taste stimuli may be “picky eaters.” They may also exhibit pica, the act of eating non-edible items such as chalk, crayons, dirt, etc.
Vision: Children with sensory processing disorder of the visual system may have difficulty going down stairs; poor hand-eye coordination; pain, watering, or discomfort when required to perform visual work; frequent headaches or stomachaches after visual work or school; or difficulty copying. These children may be unable to read without losing place or aloud. They may also rub their eyes after use.
Auditory: Children with auditory processing disorder may become upset with loud or unexpected noises; hum or sing to screen out unwanted noises; be easily distracted by loud noises; enjoy loud sounds and repeat them several times; have difficulty with clothes that make noise; notice or are bothered by environmental noises that most would screen out (e.g. refrigerator, air conditioner, ticking clocks); have difficulty with verbal prompts ; cover ears frequently; or speak in a loud voice to screen out incoming noise.
Vestibular: Children with vestibular processing disorder may have a history of repeated ear infections and/or ear tubes. They may also display avoidance of movement, especially head movement; head banging; motion sickness; avoidance of merry-go-rounds or rollercoasters; excessive spinning or watching things spin; inability to read or write in cursive; dizziness or nausea caused by watching things move; hearing problems; inability to sustain listening without moving or rocking; problems with balance; difficulty walking on uneven surfaces; or the need to move fast.
Proprioception: Children with proprioceptive processing disorder may need to have physical contact with another person, i.e. clinging or the need to be held, swaddled, and snuggled. These children may exhibit hysteria over washing hair or pulling shirts over the head, avoid of eyes-closed activities, difficulty falling asleep and staying asleep, sleep walking or falling out of bed, extreme restlessness while sleeping, need for heavy covers, clothing, or a backpack to feel grounded, or need to have light on to sleep. Some children avoid team sports, have an aversion to crowds, are clumsy, trip over their own feet, bump into things, have difficulty grasping mathematical concepts, or are unable to accept physical and social boundaries.
Children with SPD can often be misdiagnosed as having ADD, ADHD, or various other neurodevelopmental disorders. This is because SPD often co-exists with ADD, ADHD, Autism Spectrum Disorder, Obsessive Compulsive Disorder, Anxiety Disorder, Traumatic Brain Injury, and various learning disorders. Children with SPD are often misunderstood and labeled as aggressive, clumsy, inattentive, or “difficult.” The neurological disorganization resulting in SPD can occur three different ways: the brain does not receive messages due to a disconnection in the nerve cells; sensory messages are received inconsistently; or sensory messages are received consistently, but do not connect properly with other sensory messages.