What is the Difference Between Sensory Processing Disorder and Autism?

What is the Difference between SPD and Autism?

The answer to this question is easy... I have no idea. Autism and SPD are both neurological conditions that can impact the way the brain perceives and responds to information.  But what are the differences?

This topic is of special interest to me.  I am currently struggling with whether or not Sensory Processing Disorder explains all of the intricacies of JC's behavior.  For example, at 18 months the assumption was made (not by me, but by medical professionals) that he would most likely develop autism because of his severe sensory issues and speech delay.  He was also showing several "red flags" on the M-Chat  at that time. But at his 2 year checkup, his pediatrician verbalized her surprise that he had shown marked improvement on his M-Chat scores and was not inclined to test him for Autism.  I believe that because of the early intervention and intensive therapy both during sessions and at home, he has shown so much improvement that Autism is no longer an assumption, but merely a possibility (and yes, it is still a possibility).  There have been new and worsening behaviors over the past few months and I can't help but wonder (and by "wonder" I really mean "over-analyze" and be "paranoid" about) whether or not he may actually have signs of Autism.  So the research behind this blog entry was as much for me as it was for any reader.  I needed to know the answer to the question: What is the difference between SPD and Autism?

I started my research with definitions:

One Autism publication that I found describes autism as "a group of developmental disabilities that affect a person's ability to understand what they see, hear and otherwise sense."
Wikipedia describes Sensory Processing Disorder as follows: "sensory information may be sensed and perceived in a way that is different from most other people. Unlike blindness or deafness, sensory information can be received by people with SPD, the difference is that information is often registered, interpreted and processed differently by the brain. The result can be unusual ways of responding or behaving, finding things harder to do. Difficulties may typically present as difficulties planning and organizing, problems with doing the activities of everyday life (self care, work and leisure activities), and for some with extreme sensitivity, sensory input may result in extreme avoidance of activities, agitation, distress, fear or confusion."

Am I the only one that thinks those two definitions sound exactly the same?

I have to say, those medical professionals who tend to believe SPD is a subset of another disorder may have a good point.  If we can't determine a difference by definition, then how can we diagnose SPD as a singular diagnosis?  However, I tend to believe that SPD can be a stand-alone diagnosis, even though it isn't spelled out in black and white.

So what does the research suggest?

Research shows that 80%+ of children (4 out of 5) diagnosed with Autism also have sensory issues.  But the reverse is not true.  Only 2 out of every 5 children with SPD are also diagnosed with Autism (1 in 20 children have SPD while 1 in 50 are diagnosed with autism according to a new data).   For boys though, the prevalence of both disorders almost doubles.
So there seems to be a definite difference in the prevalence of Autism and SPD, and the two are certainly not the same, but the question remains, "What is the DIFFERENCE between SPD and Austism?"  How can I know that my child, who has SPD, doesn't also have Autism?

I have researched and asked questions of therapists and medical professionals and this is the most reliable answer that I can find:

The Difference between Sensory Processing Disorder and Autism:

Autism is usually characterized by 3 things: impairments in communication, social interaction, and by repetitive behaviors (such as self-stimulation: "Stimming").  Each of the 3 are required for an Autism diagnosis.  Sensory issues may play a large role in any of these factors, but a person with autism usually experiences many other symptoms besides sensory issues.  For example, according to "Love to Know Autism" a child with autism may have limited to no speech, difficulties understanding word contexts and developing a vocabulary, a need for strict routines, obsessive interest in an unusual activity or problems with social cues.

I hate to say it, but this sounds a lot like my JC.  Are his behaviors signs of Autism or just quirks?  I don't know... but I will continue to research and seek out professional opinions until I do know for sure.  But for now, I am feeling much more knowledgable and prepared to address his issues as they arise and to be the best advocate possible for the care he needs.

Update:  JC was actually diagnosed with Autism Spectrum Disorder.  For more information, click HERE.

Resources:

http://en.wikipedia.org/wiki/Sensory_processing_disorder
http://www.cbsnews.com/8301-204_162-57575282/1-in-50-u.s-school-kids-has-autism-govt-survey/
http://autism.lovetoknow.com/sensory-integration-disorder-autism
This is a great study that I found to describe the connection between symptoms of SPD and Autism actually studied the behaviors associated with SPD and how prevalent they were in children with Autism vs children without Autism.  Although most of the behaviors were described in the Autistic children, many were also found in the non-Autistic children.   http://www.sinetwork.org/pdf/tomcheck_dunn.pdf