What is Sensory Processing Disorder (SPD)?
This article is from the STAR Institute for SPD's website.
Author: STAR Institute for SPD
Definition of SPD
Sensory Processing Disorder or SPD (originally called Sensory Integration Dysfunction) is a neurological disorder in which the sensory information that the individual perceives results in abnormal responses.
Sensory processing refers to the way the nervous system receives messages from the senses and turns them into responses. For those with Sensory Processing Disorder, sensory information goes into the brain but does not get organized into appropriate responses. Those with SPD perceive and/or respond to sensory information differently than most other people. Unlike people who have impaired sight or hearing, those with Sensory Processing Disorder do detect the sensory information; however, the sensory information gets “mixed up” in their brain and therefore the responses are inappropriate in the context in which they find themselves.
The Eight Sensory Systems
Most people are surprised to find out that we actually have eight sensory systems rather than five. Learn more about these eight systems in detail.
- Visual
- Auditory
- Tactile
- Olfactory
- Gustatory
- Vestibular
- Proprioception
- Interoception
Pioneering occupational therapist, psychologist, and neuroscientist A. Jean Ayres, Ph.D., likened SPD to a neurological “traffic jam” that prevents certain parts of the brain from receiving the information needed to interpret sensory information correctly.
Causes of SPD
The exact cause of Sensory Processing Disorder has not yet been identified. Preliminary studies and research suggest that SPD is often inherited. Prenatal and birth complications have also been implicated as causal in SPD, as well as certain environmental factors. A summary of research into the causes and prevalence of SPD is included in Sensational Kids: Hope and Help for Children With Sensory Processing Disorder (New York: Perigee, 2014, 2nd edition). written by Founder and current Executive Director of STAR Institute, Lucy Jane Miller Ph.D., OTR
Ten Fundamental Facts About SPD
When extended family, teachers, neighbors, other parents, and service providers ask you what Sensory Processing Disorder is, the following are research-supported statements you can make.
- Sensory Processing Disorder is a complex disorder of the brain that affects developing children and adults.
- Parent surveys, clinical assessments, and laboratory protocols exist to identify children with SPD.
- At least one in twenty people in the general population may be affected by SPD.
- In children who are gifted and those with ADHD, Autism, and fragile X syndrome, the prevalence of SPD is much higher than in the general population.
- Studies have found a significant difference between the physiology of children with SPD and children who are typically developing.
- Studies have found a significant difference between the physiology of children with SPD and children with ADHD.
- Sensory Processing Disorder has unique sensory symptoms that are not explained by other known disorders.
- Heredity may be one cause of the disorder.
- Laboratory studies suggest that the sympathetic and parasympathetic nervous systems are not functioning typically in children with SPD.
- Preliminary research data support decades of anecdotal evidence that occupational therapy is an effective intervention for treating the symptoms of SPD.
– from Sensational Kids: Hope and Help for Children With Sensory Processing Disorder (SPD ) p. 249-250 by Lucy Jane Miller, PhD, OTR
Click here to read more.- Raana Smith