Groundbreaking study reveals biological basis for sensory processing disorders in kids

By Sharon Heller, PhD

Sensory processing disorder (SPD) is a condition in which the brain misperceives sensory information and processes information inefficiently. Such misperception profoundly affects how well a person makes sense of, responds to and functions in the world.

How SPD plays out

A person with SPD may over-respond to sensation and jump out of their skin at a car honk or under-respond and barely notice the sound, putting themselves in danger. They may be clumsy, have poor balance, confuse right from left, write sloppily or be slow at comprehending and responding to what is heard or seen. Some with SPD experience only one of these conditions, others experience all.

Constantly being thrown off-center creates much stress, confusion, frustration and irritability that leads to or exacerbates a slew of psychiatric disorders including anxiety, depression, obsessive-compulsive disorder and depersonalization. As a result, SPD gets commonly misdiagnosed as psychiatric.

SPD is common but overlooked

Though SPD is estimated to occur in at least 10% of all school children, it is not widely known. It has been overlooked as a distinct condition, because it often occurs in children who also have ADHD or autism. Further, until now, the disorder has not had a biological marker and, for this reason, was denied inclusion in the new DSM-5, the psychiatrists’ manual of mental disorders.

Groundbreaking study puts SPD on the map

Now, a new groundbreaking study from San Francisco’s Benioff Children’s Hospital shows that kids with SPD have differences in brain structure compared with other kids. This finding reveals for the first time a biological basis for SPD that sets it apart from other neurodevelopmental disorders.

In the study, the researchers used an advanced form of MRI called “diffusion tensor imaging” on the brains of 16 boys, ages 8 to 11, with SPD but without a diagnosis of autism or prematurity. They compared their results with 24 typically developing boys who were matched for age, gender, right- or left-handedness and IQ.

The results showed that the boys with SPD had abnormal tracts of white matter in their brains, particularly in the back part of the brain in areas known to play roles in tactile, visual and auditory systems. The strongest correlation was for auditory processing.

“These are tracts that are emblematic of someone with problems with sensory processing,” study researcher Dr. Pratik Mukherjee, M.D., Ph.D., a professor of radiology and biomedical imaging and bioengineering at UCSF, said in a statement. “More frontal anterior white matter tracts are typically involved in children with only ADHD or autistic spectrum disorders. The abnormalities we found are focused in a different region of the brain, indicating SPD may be neuroanatomically distinct.”

The researchers concluded that the abnormal microstructure of sensory white matter tracts likely alters the timing of sensory transmission and results in the processing of sensory stimuli and integrating information across multiple senses as difficult and even impossible.

Sources for this article include:

http://www.sciencedaily.com

http://www.sciencedirect.com

About the author:
Sharon Heller, PhD is a developmental psychologist who specializes in books on holistic solutions for anxiety, panic and sensory processing disorder (SPD). She is the author of several popular psychology books including “Uptight & Off Center: How sensory processing disorder throws adults off balance & how to create stability” (Symmetry, 2013), “Anxiety: Hidden Causes, Why your anxiety may not be ‘all in your head’ but from something physical” (Symmetry, 2011) and “Too Loud, Too Bright, Too Fast, Too Tight, What to do if you are sensory defensive in an overstimulating world” (HarperCollins, 2002). She can be contacted via email at [email protected] and via her website, www.sharonheller.net. You can also follow her blog at http://sharonhellerphd.blogspot.com