A pilot study suggests playground equipment can provide social and emotional benefits for children with sensory disorders.

By Jeff Link

Lucy Miller lost her sight when she was 16 and, in 1970, underwent one of the nation’s first corneal transplants. A procession of specialists flitted in and out of her recovery room—doctors, nurses, residents, fellows—but she recalls thinking that only the occupational therapist was interested in her as a person.

Shortly after her release from the hospital, she abandoned her plans to go to law school and headed to graduate school at Boston University to study occupational therapy. It wasn’t only the care and attention of her former occupational therapist who had led her to this decision. In the hospital, over several months when her eyes were surgically detached from her skull, she noticed her other senses had grown sharper. She wondered why, neurologically, this had happened, and was determined to find out. So, in her early twenties, still in graduate school, she embarked on a summer mentorship at the Torrance, California, clinic of Jean Ayers, the originator of a then-emerging field exploring the relationship between the sensory processing dysfunction and the behavior of children with disabilities.

Nearly half a century later, Miller, who is the clinical director of the STAR Institute for Sensory Processing Disorder just south of Denver, has become one of the nation’s preeminent scholars on sensory processing disorder (SPD). This term is used to describe difficulty with “one or more of the sensory processes that occur along the neurological pathway, from detecting stimulation to regulating the input and output, to interpreting the sensations correctly, to responding accurately, and finally, to turning the sensory input into meaningful responses,” as she explained in her 2014 book, Sensational Kids: Hope and Help for Children with Sensory Processing Disorder.

Falling into six subtypes and described by a range of symptoms, sensory processing disorders are difficult to describe succinctly. A child who overresponds to stimuli, Miller explained to me, might be intensely bothered by the sound of a fire engine. An underresponsive child might hold a light bulb long enough to get burned. A child with a sensory-based motor disorder may have trouble coordinating movement to print legibly, put on socks, or play team sports. Children with SPD may bite, push, or fight. Many are kicked out of schools.

The disorder gained widespread public attention after a report by the Hartford Courant in partnership with the PBS news program FRONTLINE revealed that Adam Lanza, the Newtown, Connecticut, school shooter, was among those with SPD. Diagnosed with sensory integration disorder—now referred to as sensory processing disorder—Lanza was extremely sensitive to physical contact and loud noises. His isolation and psychological unrest represent the extreme edge of a dimensional disorder that Miller says can compound across a lifetime. “The disorder starts when a person has problems adapting to life. These kids become loners, they don’t have friends; the social aspect of their life is really impacted and critical,” she says.

But playgrounds may be able to help children avoid such painful trajectories. A six-month pilot study led by Miller and published in the peer-reviewed Journal of Occupational Therapy, Schools, and Early Intervention showed that school-aged children engaging at an inclusive playground designed by Landscape Structures demonstrated increased verbalization and positive affect, and showed instances of motor planning, symbolic play, novel use of play materials, and self-regulation. These behaviors are associated with the treatment goals for children with sensory challenges and are beneficial for the development of all children, Miller says.

The pilot study was conducted at the STAR Institute, where Miller directs a multidisciplinary clinical team that provides treatment for roughly 700 families a year. It used a behavioral coding scheme developed by Miller, along with Stephen Camarata, a professor of psychiatry and behavioral science at Vanderbilt University, and Sarah Schoen, an occupational therapist at the STAR Institute, to evaluate playground equipment used by 140 typically developing children and 41 children with a variety of developmental disabilities, including autism, attention deficit hyperactivity disorder (ADHD), and sensory and regulatory disorders. During weekly two-hour playground sessions, children were observed by video cameras and recorded using wireless microphones attached to adults on the playground who remained within range of the majority of the children.

The coding scheme measured the effectiveness of six types of playground equipment based on the percentage of time children expressed certain behaviors while using the equipment. A total of 32 hours of videotape were analyzed. Using a method common to speech therapy studies, the researchers noted whether behaviors occurred at least once or did not occur at all during 60-second intervals, then extrapolated the results across five domains: sensory features, social interaction, self-regulation, motor skills and motor planning, and play level. At a roller slide, for instance, children exhibited social interaction via “spontaneous verbalization” for 37 percent of the observed time and “turn taking” for 19 percent of the observed time.

When analyzed, behaviors such as digging in a sand and water table, climbing a Möbius strip-shaped climbing wall, sliding down the rungs of a roller slide, and spinning on the spinner (a bowl-shaped merry-go-round with seats providing postural support) revealed correlations between sensory stimulation and social interaction, motor planning and self-esteem, and play levels and positive affect. A preliminary indication is that a sensory-rich playground, aside from being fun, can support multiple areas of childhood development. “I think people don’t realize playgrounds are about more than play. They are the foundation to children’s physical development, social and language development, and competence in daily life,” Miller says.

Catherine Lord, who is a professor of psychology in psychiatry and founding director of the Center for Autism and the Developing Brain at New York-Presbyterian Hospital, and was not involved in Miller’s study, says the study is also significant for its methods. Unlike a randomized controlled trial in a clinical setting, a study at a playground in an everyday social context is difficult to conduct using hard science. “There isn’t a lot of data related to everyday opportunities for kids with autism spectrum disorders, or other kinds of disorders, to be exposed to physical experiences and peer interaction. I think it is a really great step forward in the right direction.”

A particularly promising aspect of the study, Miller says, relates to the proprioceptive sense, which, along with the vestibular sense, gives us awareness of movement, speed, and pressure on the joints and muscles. Providing the right level of input to these “hidden” senses rooted in the nervous system, she believes, may hold promise as a way to help children with SPD self-regulate their behavior and relate to their peers more easily.

One telling case study involved a child so overresponsive to touch that he refused to wear underwear or brush his teeth. As explained in the report, an increase in proprioceptive stimulation on equipment such as the Möbius climber and roller slide paralleled an increase in his self-regulation. It also paralleled increases in the boy’s use of prompted and unprompted speech, displays of positive affect, and demonstrations of pride in his accomplishments (e.g., “Look, Mom, I did this myself!”).

Miller says several children made similar behavioral leaps. “Two kids playing in the sand and water were digging to China—digging, digging, digging—until one hit bottom three feet down and said ‘I made it. I made it. I got to China.’ Another who’d hardly ever spoken before said, ‘Thank goodness. Everybody in China will be hydrated.’ These are kids who people think can’t speak.”

Both the children she describes had been diagnosed with autism. This is noteworthy as there is empirical debate over whether SPD is a distinct disorder or a collection of symptoms explained by other neurological deficits, such as autism or ADHD. “So many disorders involve the senses that to call these abnormalities SPD may be like diagnosing a person with a headache. A headache is not a diagnosis,” Lord says. “But the points I’m making shouldn’t belie the fact that occupational therapy and other kinds of treatment are very important and that the use of movement, space, and objects, along with social connections, can improve the lives of people.”

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders does not recognize SPD as a condition separate from autism. “I’ve tried for 18 years to get it listed as a separate diagnosis without success. All children with autism have sensory problems. Most with sensory disorders don’t have autism. [SPD] is not a disorder in the sense of a broken leg or gall bladder; everybody falls somewhere on the dimension. Many aspects of mental disorders have this problem,” Miller says.

For a long time, the design community didn’t get it right, says Chad Kennedy, ASLA, a principal landscape architect at O’Dell Engineering. “Sensory integration has been hugely overlooked in the context of inclusive design. When people talk about inclusion, they tend to focus on physical disabilities, wheelchair access. Unfortunately, I think, many parents with children on the autism spectrum didn’t enjoy going to the playground and avoided it because overstimulated children misbehaved,” Kennedy says.

However, this is beginning to change. Kennedy points to Sunridge Park in Rancho Cordova, California, where O’Dell Engineering’s incorporation of tiered sand beds, loose clay, a tuned drum set, and a spray pad offers children a variety of sensory experiences. O’Dell Engineering has also developed an inclusive play environment audit, a quantitative evaluation tool assessing play features—a grassy maze, nature playhouse, or xylophone—based on the cognitive, sensory, physical, and social opportunities they provide.

Greg Miller, FASLA, a principal at MRWM Landscape Architects and the current president of the American Society of Landscape Architects (and no relation to Lucy Miller), says his exposure to Lucy Miller’s ideas at ASLA’s annual meeting several years ago—and the subsequent talks they’ve given together—has inspired a sensory-rich design philosophy evident in several neighborhood parks and schools his firm has designed. The approach extends beyond equipment specification to include siting considerations, developmentally graduated play spaces, side-by-side play elements, mixed scale use, and the integration of richly textured natural and manufactured elements.

Set against the Sandia Mountains, Four Hills Village Park in Albuquerque, New Mexico, as Miller describes it, is one example. Its tree canopy shades a path winding over hills and bridges. With little visible separation between the broader park and the play area, the path leads to a custom-built Landscape Structures play tower resembling an Ewok village with pods, net climbers, ropes, and bridges. The play area is surfaced in loose, engineered wood fiber to create a “zero-edge play area” that blurs the transition between a playground and the rest of a park.

Maggie Daley Park in Chicago by Michael Van Valkenburgh Associates, Inc. and Governors Island in New York by West 8 are other examples of sensory-based design that, until recently, landscape architects practiced mostly intuitively, Greg Miller says. Now those instinctive decisions may have a stronger basis in science. “Evidence-based documentation is a demonstration of the value of this approach. A lot of landscape architects are embracing these ideas and doing very cool projects incorporating these elements. But instead of operating intuitively, they will be able to code it back to research,” he says.

Jeff Link is a journalist based in Chicago. His work has appeared in Fast Company, Architect, and other publications. He is a graduate of the Iowa Writers’ Workshop.