What is SPD?
SPD is the acronym for Sensory Processing Disorder.
“Sensory Processing Disorder is a neurological disorder that is like a virtual traffic jam in the brain. The information from all eight senses is misinterpreted which causes a child (person) to often act inappropriately.”
The Sensory Processing Disorder Foundation’s website says the following:
“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.”
To get a better understanding of SPD, let’s break the SPDF’s definition down into a more consumable definition.
“…the way the nervous system receives messages…” — this is referring to the messages received (also known as ‘input’) from all eight senses and how they are conveyed to the brain through the nervous system. The brain is the key component to the nervous system, as that is where the ‘processing’ occurs. By ‘processing’, we are in very basic terms referring to whether or not the brain ‘understands’ those signals. When the brain misinterprets the meaning of those signals, and can’t process them appropriately, it leads to an inability to turn them into appropriate motor and behavior responses (also known as ‘output’). Example: If the ‘input’ isn’t understandable by the processing system then the ‘output’ becomes jumbled or non-traditional in nature.
“…appropriate motor and behavior responses…” – ‘appropriate’ here refers to the assumed way that a child should respond – if something is too loud, they should pull their ear back, if something is quiet, they shouldn’t scream it is too loud. The word ‘motor’ refers to a physical response – how your body moves as a result of the information from the brain, and then ‘behavior’ how the child continues to respond (over or under reactions). Example: Loud unexpected BOOM! Kid cringes and covers his ears (motor), then screams and runs away (behavior).
There are three types of Sensory Processing Disorders and formal definitions can be found here. Here is a summary of each type:
Type I: Sensory Modulation Disorder – These are the sensory avoiders or sensory seekers; their senses are under or over reactive (i.e. they avoid touch or sound or like to crash or jump or etc.).
Type II: Sensory Based Motor Disorder – This is where discrimination of the senses causes confusion, clumsiness and impacts gross and fine motor skills (i.e. crawling, walking, writing, sight, low muscle tones.).
Type III: Sensory Discrimination Disorder – This is where the senses become confused so it’s referred to as “discrimination”. For example the body has a problem determining spacial awareness (movement and balance), differing pain from pleasure, hot and cold. Also, sounds, smells and tastes can come across very different then they should to be interpreted by the brain.
The Sensory Processing Disorder Foundation’s (SPDF) website has a wealth of great information. A helpful analogy quoted from Dr. Jean Ayres, the pioneer credited with research and education of SPD can be useful in explaining to others in simple terms this disorder.
“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.”
Common misconceptions about SPD:
“SPD is on the Autism Spectrum” or “SPD is a mild form of Autism” – FALSE. Although a significant portion of kids with ASD do have sensory issues (estimates range as high as 85%), the opposite is not true. Many children with SPD do not have ASD. So, to recap, SPD is NOT on the Autism Spectrum.
“They are trying to get SPD added to the Autism Spectrum in the DSM” — FALSE. The work being spearheaded by the SPD Foundation and Dr. Lucy Jane Miler is to get SPD recognized as a ‘stand alone disorder’ in the DSM-IV. You can find more info on their site by clicking here.
“SPD just means that a child doesn’t like loud noises” – FALSE. SPD is not just a single symptom, nor is it about ‘sensory preferences’. Children with SPD have sensory differences severe enough to affect their social and academic development. It is much more complex than ‘not liking loud noises’. And, although children with SPD can avoid sensory input, they can also seek sensory input.
“SPD is the new ADD” – FALSE. I am not going to combat the theory that we as a country (or society in general) have become increasingly consumed by labels, because I agree. However, I would like to say for the record, Sensory Processing Disorder is real. Just ask any of the thousands of families that read my blog every month, this is a true health issue that needs to be recognized so that these children and families can get the help they need.
“SPD affects all 5 senses” — INACCURATE. This is probably my biggest pet peeve. We have 8 senses – EIGHT SENSES!! Touch, Taste, Smell, Hearing, Sight, Vestibular, Proprioception and Interoception. If you are reading anything (blog, tweet, Facebook, article, newspaper, etc) and they say that SPD affects 5 senses – STOP reading. If they do not know at a minimum that there are 8 senses, this person is not an expert.
For more information on Sensory Processing Disorder, please visit www.spdfoundation.net.






