According to research, children on the autism spectrum often have abnormal sensory behaviors, as they have difficulty processing sensory stimuli. Furthermore, the brains of children with autism are wired very differently from other children with sensory processing disorders (SPD). Sensory processing disorders consist of sensitivities to sound, light, and touch. In addition, those that suffer from these disorders often have low motor skills and a lack of focus. For example, some children with SPD cannot hold an object properly, or focus on one subject for a long time. In contrast, many individuals on the autism spectrum have fixations on one thing and can spend a great deal of time focusing on it.
In a study that was recently conducted at UC San Francisco, researchers analyzed the brains of 15 boys with autism, and 16 boys with SPD. In addition, a control group of 23 neurotypical boys were used in the study. All participants were between the ages of 8 and 12. Researchers studied white matter, the area that links various parts of the brain, with an MRI. On average, the boys with autism and the boys with SPD both exhibited reduced brain connectivity in areas of the brain involved in sensory information. However, the boys with autism showed deficits in parts of the brain associated with social and emotional processing and abilities.
Dr. Pratik Mukherjee, professor of radiology and biomedical imaging at UCSF, lead author of the study, states, “With more than 1 percent of children in the U.S. diagnosed with an autism spectrum disorder, and reports of 5 to 16 percent of children having sensory processing difficulties, it’s essential we define the neural underpinnings of these conditions, and identify the areas they overlap and where they are very distinct.” Over 90% of children with autism disorders also have some type of atypical sensory behavior, but it has been difficult to pinpoint the differences that lie in sensory issues between those with autism and those with SPD. This study, published in the journal PLOS ONE, is the first of its kind, as it compared structural connectivity in the brains of children with an autism diagnosis versus those with an SPD diagnosis, along with a group of typically developing boys.
Dr. Elysa Marco, cognitive and behavioral child neurologist at UCSD Benioff Children’s Hospital San Francisco, another author of the study, states, “One of the most striking new findings is that the children with SPD show even greater brain disconnection than the kids with a full autism diagnosis in some sensory-based tracts.” She continues, “However, the children with autism, but not those with SPD, showed impairment in brain connections essential to the processing of facial emotion and memory.”
This study was incredibly significant in allowing parents and doctors to have more insight as to why children on the autism spectrum may suffer from sensitivities to various stimuli, and how they are different from the way children with SPD suffer from them. Larger studies will need to be conducted to understand the basis for differences in sensory and neurodevelopmental difficulties. Sensory challenges can be a huge obstacle in the lives of those with autism and those with SPD, so the next challenge is to configure ways to accommodate these sensitivities to make these children more comfortable in their surroundings.