Tabetha Marsh dreaded going to the grocery store with her 3-year-old son, Brody. With all the noise and bright lights, he would have meltdowns.

“He would literally bite me throughout the grocery store. It was really hard,” says Ms. Marsh, who lives in Hebron, Ky.

Ms. Marsh took Brody, now 6, to an occupational therapist who determined he had a sensory-processing disorder, or SPD, a condition in which the body and brain have difficulty processing and responding to sensory stimuli in the environment. Some people with SPD are hypersensitive to loud noises or different textured foods, for instance; others may be agitated by the touch of a clothing tag. Still other children with SPD may show hardly any response to external stimuli.

SPD is believed to affect 5% to 16% of children in the U.S., various studies have found.

Not all doctors accept the existence of SPD, which isn’t listed in the Diagnostic and Statistical Manual of Mental Disorders. SPD is often found in children who have autism, ADHD or another such disorder. The American Academy of Pediatrics said in a 2012 policy statement that it remains unclear whether children with sensory problems have a distinct condition, or whether such challenges are symptomatic of other developmental and behavioral disorders.

Karen Harpster, director of occupational therapy research at Cincinnati Children’s Hospital Medical Center, says occupational therapists at the hospital treat dozens of SPD patients every week. SPD can affect just one sense, such as hearing, touch or taste, or multiple senses, she says. Sensory-processing problems can also affect the body’s vestibular system, creating difficulties with balance, or the proprioceptive system, leading to problems with clumsiness and body positioning, she says

Adults can have SPD, though it is often less apparent because they have learned ways to compensate, Dr. Harpster says. She says she has worked with some children with SPD who are academically gifted and don’t have autism or ADHD. “I have treated kids before that don’t have any other outlying main diagnosis,” she says.

A common treatment at Cincinnati Children’s is called sensory integration, where children engage in play-based activities that help them learn appropriate responses, Dr. Harpster says. For example, children may do an obstacle course with a variety of sensory activities, including different types of swings to help with balance problems. The therapy aims to help patients adapt so they can better respond in the real world.

“We’re still developing evidence to support sensory-based treatment,” Dr. Harpster says. A common intensive program at Cincinnati Children’s involves three sessions a week for about six weeks, although the frequency can vary, she says.

Issues from SPD never really completely go away, though symptoms get more manageable, says Lucy Jane Miller, founder of the STAR Institute for Sensory Processing Disorder, in Denver. The aim is to teach people coping skills, which at STAR involve an intensive treatment program of some 30 one-hour sessions nearly every day for several weeks. The cost is about $175 per session. While insurance doesn’t cover treatment for SPD, since it isn’t a recognized disorder, most plans will pay for the therapies if they are part of another diagnosis such as autism, ADHD or muscle weakness.

Treatments at the STAR Institute are play-based and include parents. Children in sensory gyms are put in swings, nets or ball pits and exposed to different stimuli so they can learn to detect, regulate and interpret sensations and produce the appropriate motor and behavioral responses. “You try to give them sensation playing with them,” says Dr. Miller, who has degrees in occupational therapy and early-childhood special education. Most of her patients are between 3 and 7 years old. STAR began working with adults with SPD in July.

Electronic devices have created problems for children with sensory problems, Dr. Miller says. “Kids don’t get to tap into their sensory systems anymore. They’re not outside rolling around and playing,” she says.

The goal of treatment is to develop habits and routines for families to help children better regulate their responses to sensory inputs, Dr. Miller says. Children might eat crunchy food for breakfast, or have a wrestling match with mom in the morning. “We make a sensory lifestyle for children so they are getting lots of sensation before they go to school and sit all day,” she says.

Research into the brain structures of children classified as having SPD suggests a possible biological basis for the disorder, says Pratik Mukherjee, a professor of radiology and bioengineering at University of California, San Francisco. Studies showed that children with SPD had less-developed white matter mostly in the back of their brain compared with typically developing children. This posterior region of the brain is where a lot of sensory processing takes place, he says.

The findings came in a small 2013 study published in the online journal Neuroimage: Clinical, involving 16 children with SPD—all boys—and 24 typically developing children. A follow-up study, published earlier this year in Frontiers in Neuroanatomy, found similar results testing 81 children, including boys and girls. Dr. Mukherjee, who was the senior author on both studies, says more research is needed to determine if there is a biological basis for SPD. “It points in that direction,” he says.

After seeing an occupational therapist, Ms. Marsh’s son, Brody, was found to have problems with balance and body positioning, in addition to hypersensitivity to touch. He started with weekly occupational therapy sessions and now goes to Cincinnati Children’s every other week, in addition to getting support in school. His therapy includes swings, spatial-orientation exercises and calming props. Ms. Marsh hopes that with a “sensory diet”—a personalized plan of activities that give Brody the sensory input he needs to better manage his daily activities—she can cut back on occupational therapy.

Brody still has difficulties at the grocery store, but Ms. Marsh has learned some coping strategies. Instead of an open grocery cart, she places her son in a car cart to shelter him from some of the overhead lights. She also gives him headphones to block some of the noise.

And when Brody shows signs of having a meltdown, Ms. Marsh has learned to intervene with deep pressure hugs, which calm him. “He is learning to say, ‘I need a big hug,’ when he needs it.”

Source: The Wall Street Journal