Sensory Integration Dysfunction
From Freepedia
Sensory Integration Dysfunction is a neurological disorder pertaining to a person's ability to register and process information from their five commonly known senses (vision, auditory, touch, olfaction, and taste) plus their sense of movement (vestibular) and their positional sense (propioception)[1]. Sensory integration disorders span a wide range of neurological conditions, including autism spectrum disorders, dyslexia, pervasive developmental disorder, multiple sclerosis and speech delays, among many others.
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Meaning of sensory integration
Sensory integration is the ability to take in information through the senses of touch, movement, smell, taste, vision, and hearing, then combining the resulting perceptions with prior information, memories, and knowledge already stored in the brain, and to then derive coherent meaning from processing the stimuli. The mid-brain and brainstem regions of the central nervous system are generally recognized as the control locus for sensory integration, where complex interactions enable processes including coordination, attention, arousal, autonomic function, emotions, memory, and higher level cognitive functions.
Sensory integration and hypersensitivities
Sensory integration disorders vary between individuals, and dysfunctions of this type can range from very mild and almost undetectable to very noticeable and severely affecting a person's daily life.
Kids can be born hypersensitive, or hyposensitive, to varying degrees, in any one or more of their five senses. Hypersensitivity is also known as sensory defensiveness. An example of an hypersensitive child is one who complains their clothes hurt or itch, or lighting is too bright. Another example is someone who does not like to be touched or caressed, or someone who will not look directly into the eyes of another person. An example of a child or adult with hyposensivity is one who throws themself into a wall in order to get a sense of their body.
Sensory integration dysfunction generally tends to affect three over-riding systems inside the body: tactile (touch), vestibular (balance-located in the ears), and proprioceptive (awareness of where body parts are located spatially in relation to one another). Hypersensitivities affecting these systems may complicate a person's sensory integration disorder, more than a simple hypersensitivity confined to either hearing or sight, which involve integrative processes confined to the brain. A proprioceptive sensitivity may significantly impair a person's awareness of the boundaries of their body, like where the beginning and end of one's arms are, or where they are in relation to the rest of the body. Tactile hypersensitivities may manifest in many different ways. Someone who has a vestibular sensitivity may really like roller coaster rides because of their centrifugal force, which gives extreme stimulation to their vestibular system.
Sensory integration and autism spectrum disorders
Sensory integration dysfunction is a common symptom of autism [2]. Often, autistic children receive too much sensory stimulation through one or more of their senses, and in order to turn down the volume, they tend to avoid people, noises and bright lights. Autistic children do not develop the neurotypical capacity to integrate and modulate information from the five senses.
In her book, Thinking in Pictures, Temple Grandin reports the results of a survey about sensory integration in a relatively small population with autism spectrum disorders from one center:
- "A survey of sensory problems in 30 adults and children was conducted by Neil Walker and Margaret Whelan from the Geneva Centre for Autism in Toronto. Eighty percent reported hypersensivity to touch. Eighty-seven percent reported hypersensivity to sound. Eighty-six percent had problems with vision. However, thirty percent reported taste or smell sensivities."
Alternative views
Not everybody agrees with the notion that hypersensitive senses is necesarily a disorder. Even if hypersensitivity is the most common in autism, insensitivity to pain is also common. Additionally, there is no proof for the idea that hypersensitivity would necesarily be a result of sensory integration issues.
It is possible that misdiagnosis is also a problem with the construct of Sensory Integration Dysfunction. Some experts claim that Occupational Therapists incorrectly apply this label to individuals with attention difficulties or who simply don't put forth any effort during assessments. For example, a student who fails to repeat what has been said in class (due to boredom or distraction) is referred for evaluation for sensory integration dysfunction. The student is asked to listen to signals coming from either side of a pair of headphones and combine them to form words. The student is still bored or distracted, and so does poorly on the test. The assessor concludes that the student has sensory integration dysfunction, while, in fact, he may have a disorder of auditory processing (also overdiagnosed), poor auditory attention, a mood problem, or may fail to put forth adequate effort on the task for other reasons. Diagnoses based on single tests are unreliable, and integrated assessment utilizing multiple sources of information is the preferred means of diagnosis, especially in children.
There is a large percentage of children who receive the diagnosis of sensory integration dysfunction who might be better understood as having anxiety problems or even behavioral disorders. These problems can make a child look reactive, "touchie", or unpredictable, and manifest in a manner similar to that characterized by occupatinal therapists as sensory integration dysfunction. And while this diagnosis is accepted widely among occupational therapists and also educators, these professionals have been criticized for overextending an already-poorly-supported model that attempts to explain emotional and behavioral problems that are better (and more simply) explained in other ways.
It should also be understood that there is general agreement that some children do have oversensitivity to many physical stimuli, the existence of this relatively small subset of children has lead to a general pattern of overdiagnosis in children who "look the same" but have other problems, and there are relatively few medical and psychological practictioners who agree that sensory integration dysfunction is the foundational problem in most children with this diagnosis.
While the physical methods employed by occupational therapists as treatment for SID are often paliative (they make the child feel better--much as a nice massage or physical contact would make anyone feel better), children misdiagnosed with sensory integration dysfunction will not receive appropriate psychological treatment (e.g., cognitive behavioral therapy) if they remain misdiagnosed.
See also
External links
- Autism.org - 'Sensory Integration', Cindy Hatch-Rasmussen, MA, OTR/L
- Genetic.org - 'Sensory Integrative Dysfunction', Linda C. Stephens, MS, OTR/L, FAOTA
- quackwatch.org - 'Why Sensory Integration Disorder Is a Dubious Diagnosis', by Peter L. Heilbroner, MD, PhD
- SensoryInt.com - Sensory Integration International
- AdultSID.com - E-mail list for adults with Sensory Integration Dysfunction
