Sensory Processing Disorder Linked With Brain Structure Differences

Kids with sensory processing disorder (SPD) -- a condition where common sensations are unbearable and disrupt daily life -- have differences in brain structure compared with other kids, according to a new study. The condition has yet to be recognized by the Diagnostic and Statistical Manual, the psychiatrists' manual of mental disorders.

"We are just at the beginning, because people didn’t believe this existed," study researcher Dr. Elysa Marco, M.D., who is a cognitive and behavior child neurologist at the University of California, San Francisco's Benioff Children's Hospital, said in a statement. "This is absolutely the first structural imaging comparison of kids with research diagnosed sensory processing disorder and typically developing kids. It shows it is a brain-based disorder and gives us a way to evaluate them in clinic."

The study, published in the journal NeuroImage: Clinical, involved studying the brains of kids with SPD. Researchers conducted diffusion tensor imaging on the brains of 16 boys ages 8 to 11, all who have SPD but don't have autism or prematurity, as well as 24 similar boys without SPD.

Researchers found that the boys with SPD had abnormal tracts of white matter in their brains, particularly in the back part of the brain in parts known to play roles in tactile, visual and auditory systems.

"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."

According to the Sensory Processing Foundation, SPD (sometimes also known as sensory integration disorder) occurs when the brain can't properly process sensory signals into the right responses. The SPD Foundation explains:

Pioneering occupational therapist 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. A person with SPD finds it difficult to process and act upon information received through the senses, which creates challenges in performing countless everyday tasks. Motor clumsiness, behavioral problems, anxiety, depression, school failure, and other impacts may result if the disorder is not treated effectively.

A 2010 article from McClatchy Newspapers explained that people who have SPD may find clothing with tags unbearable to wear, or that a simple poke may feel instead like a shove.

However, the American Academy of Pediatrics does not recommend that pediatricians diagnose patients with the condition. The lead author of the AAP recommendations, Dr. Micihelle Zimmer, who is a professoor in the Department of Pediatrics at the University of Cincinnati, explained to ABC News that more research is needed to confirm its identity as a distinct disorder.