As a baby and toddler, Donna Kacin's son seemed fussier and more frequently out of sorts than other kids his age. Loose-fitting socks or tags in the backs of his shirts would bother him no end. Any sudden noise would cause him to clap his hands over his ears. The only foods he would eat were white -- bagels, noodles, bananas and cheese. Certain odors, such as those from pizza or hot dogs, would send him running from the room. And everyday transitions, such as leaving the playground, would induce meltdowns.

"Everything seemed to be a little harder for him," recalled Kacin, a mother of two who lives in the District. "He protested a lot of things that other children seemed to take in stride."

Such behavior often leaves doctors -- and parents -- scratching their heads. Many wonder if the baffling behavior is due to food allergies, an anxiety order, attention-deficit hyperactivity disorder (ADHD) or some other problem. Often they have the child tested for these conditions.

But now some of these parents, including Kacin, are being told their children may have a condition called sensory integration dysfunction, or DSI.

The term sensory integration dysfunction was coined in the 1960s by A. Jean Ayres, an occupational therapist in California who was interested in how sensory processing difficulties could interfere with the ability to learn.

Occupational therapists (OTs) and other professionals consider DSI a neurologically based disorder that makes it difficult to carry out everyday tasks. This can mean children have a hard time playing, eating, dressing, going to school and getting along with peers -- some of the most crucial early developmental challenges they face.

DSI is essentially "a problem of organizing and interpreting the sensory information once it comes in so that you can do something meaningful with it," explains Lynn A. Balzer-Martin, a pediatric occupational therapist in Chevy Chase who specializes in diagnosing children suspected of having DSI.

But not all experts in child development and psychology are aware of the condition, and others are deeply skeptical about it. Despite its acceptance as a diagnosis among occupational therapists and some parents, DSI is not acknowledged by the leading publications in psychology and child development. It is not listed in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), the bible of psychiatric disorders, or in the International Classification of Diseases (ICD-9), published by the World Health Organization.

If you search for the words "sensory integration dysfunction" in the National Library of Medicine's database, which incorporates thousands of authoritative medical publications, not a single hit comes back. Use "sensory integration disorder" and it comes back with just one reference, to sensory problems related to autism.

"It's not a part of my vocabulary," said Karin Nelson, a pediatric neurologist and chief of the neuroepidemiology branch of the National Institute of Neurological Disorders and Stroke, which is part of the National Institutes of Health. The condition is not indexed in child neurology textbooks, Nelson said. "I don't think it's a neurologically acknowledged disorder."

"It is not a distinct entity," said Paul Lipkin, an assistant professor of pediatrics at the Kennedy Krieger Institute and the Johns Hopkins School of Medicine in Baltimore and a member of the American Academy of Pediatrics's Section on Children with Disabilities. "There is no standard, universally recognized diagnosis of sensory integration disorder. In the array of human qualities, there's always a degree of variation. In the medical field, we always have to have a cutoff for what's abnormal."

Other practitioners believe that the cluster of symptoms is real and deserving of treatment, even though it is not yet scientifically validated as a distinct illness.

"It's still a relatively new area for clinicians," noted David Fassler, a child and adolescent psychiatrist in Burlington, Vt., who is chairman of the American Psychiatric Association's Council on Children, Adolescents and Their Families. "My sense is that there are kids who have this kind of problem, and we're still doing the research that's necessary to define the parameters of the disorder. It seems that some intervention programs do have some positive effects for children. If it helps for a particular child -- even if it's early in the course of understanding why it helps -- I think it's something we need to look at seriously."

In an answer in a Web-based forum for parents of children with DSI, occupational therapist Barbara Hanft explains why professionals may see the same symptoms in different ways -- and as different conditions.

"Part of the problem . . . arises out of disciplinary perspectives," she wrote. "For any individual child with learning and behavior problems, the MD may diagnose ADD or ADHD, the psychologist a mood disorder, the OT sensory integration, the speech pathologist . . . an auditory processing disorder, the teacher a specific learning disability, and so on. Each discipline has a narrow focus and defines brain function by what they have been trained to see."

Acceptance of the legitimacy of DSI may depend partly on geography. "I find that most pediatricians in the greater Washington area accept the concept of sensory integration," said Larry B. Silver, professor of psychiatry at Georgetown University Medical Center and author of "The Misunderstood Child: Understanding and Coping with Your Child's Learning Disabilities" (Three Rivers Press, 1998). "If you were to go to Minneapolis, you may not see this. It depends on where pediatricians are trained."

How Prevalent?

While reliable statistics regarding the prevalence of DSI are lacking, Lucy J. Miller, director of the Sensory Integration Dysfunction Treatment and Research Center at The Children's Hospital in Denver, estimates that about 5 percent of children have it. This estimate is based on questionnaires her research team handed out to the parents of entering kindergartners in one Colorado school district.

The causes of DSI are unknown. But there are theories.

"When there are problems in the pregnancy such as smoking, alcohol abuse, lots of stress or poor nutrition, we tend to see more of these problems," said Stanley Greenspan, a clinical professor of psychiatry and pediatrics at the George Washington University Medical School and author of "The Challenging Child: Understanding, Raising, and Enjoying the Five 'Difficult' Types of Children" (Perseus Press, 1996). The same is true among babies born prematurely and those who grow up in environments, such as orphanages, where there is little sensory stimulation, he said.

In addition, Miller said, "many kids have parents who have symptoms, which leads us to think it's genetic." For other children, it may be due to a variation in the development of the nervous system that occurs for no discernible reason.

Sensory integration struggles have been linked with problems with motor activities, language skills and other learning abilities. If a child has problems with sensory modulation -- such as being over- or under-responsive to stimuli -- this can lead to problems with attention, activity level, socializing and behavior, according to occupational therapist Balzer-Martin.

"Kids used to be sent to an occupational therapist primarily for a skill problem -- their handwriting was bad or they were having trouble with sports," Balzer-Martin says. "The newest thing in our field is kids are coming in only with modulation problems. Children with these modulation problems don't know what it's like to feel completely okay. They feel at the mercy of sensations all the time."

There are many variations in the ways children are said to be affected by DSI. Some have difficulties with only one sensory modality, such as movement, while others struggle with several. Some are over-responsive to a particular sensory input such as touch -- they might recoil from a hug or someone's accidentally brushing against them -- while others can be under-responsive, in which case a child may seek more physical contact or tactile stimulation. Some kids fluctuate between over- and under-responsive.

"It's a spectrum disorder," Miller noted. "A child can have sensory sensitivities but not have it be a problem. The disorder part comes from not being able to function well in daily life."

While parents are often appreciative of having a "good" baby who sits quietly or sleeps for hours on end, such a child could be having trouble processing what's going on around her.

"It's easier to see what a child is doing that seems out of the ordinary," says Carol Stock Kranowitz, a retired preschool teacher in Bethesda and author of "The Out-of-Sync Child: Recognizing and Coping with Sensory Integration Dysfunction" (Berkeley Publishing Group, 1998). "It's not as easy to see what a child is not doing, what isn't there. These could be kids who could fall through the cracks."

Andrea Wiener's daughter, who was born with a floppy body and low muscle tone, vacillated between extremes. When she was a baby, "if you sneezed or turned on a light, she'd start crying and it would take me an hour to calm her down," recalled Wiener, a mother of three in Potomac. A few months later, she began spending most of each day sleeping, which, her mother suspects, was her way of shutting down.

When the little girl entered preschool, she was easily overwhelmed. "She would go under the table and pretend to be asleep to shut out the sounds," Wiener said. "She was very sensitive to smells and wouldn't go into some people's houses, and she never wanted anyone to touch her. One summer, when my husband did chin-ups at the beach, she cried hysterically. She was so gravitationally insecure that she couldn't figure out how his feet got off the ground."

Early on, the Wieners consulted various specialists and their daughter started working with a physical therapist when she was 3 months old. Later, she saw an occupational therapist. After years of therapy, Wiener's daughter, now 5 1/2, "has blossomed," her mother said. Last summer, she learned how to ride a two-wheel bike, and she now participates in a gymnastics program. "She appears very happy and age-appropriate in some ways," her mother said. "But school is still very stressful to her."

Pinpointing the Problem

Some experts believe it's important to identify and treat kids with sensory integration problems as early as possible. "There's more potential to influence the nervous system to change [in positive ways] in younger children," Balzer-Martin said.

DSI is usually diagnosed by an occupational therapist, a physical therapist or a psychologist or psychiatrist who is well versed in the disorder's patterns.

Depending on the child's age, an evaluation might consist of standardized testing, as well as structured observations of a child's responses to sensory stimuli and challenges to coordination and balance. A typical diagnostic tool is the Sensory Integration and Praxis Test (SIPT), in which a child between 4 and 9 performs different activities with her hands, eyes and body while a certified therapist scores her responses.

But a child's sensory problems may not be noticed until he or she enters school.

"As a child psychiatrist, I might get a referral because the school or the parents feel the child may be having academic problems," Silver explained. "I have to sort out whether it's an emotional problem, an attention problem, a language or learning process or something else. The behavior is the message; then you go looking for the cause. If the behavior is chronic or pervasive, we start thinking of this neurologic picture."

Complicating the picture is the fact that some behavior often attributed to DSI can coexist or share symptoms with other disorders such as ADHD, speech and language problems or learning difficulties. Some experts quarrel with the attachment of multiple labels to a child's problems.

"A child may meet the criteria for DSI and ADHD, but does that mean a child has both?" Greenspan asked. "You could have a fever and pneumonia -- does that mean you have two independent conditions? [DSI and ADD] are not mutually exclusive conditions. These are behaviors that can be classified in different ways."

The Treatment

When DSI is the diagnosis, therapy generally includes controlled exposure to sensory stimuli. Rather than working on particular skills, occupational therapists who treat DSI try to stimulate whichever sensory systems underlie the skill or behavior the child is struggling with. If a child is over-sensitive to sound but loves movement, a therapist might encourage him to blow on a whistle while swinging. If he's under-sensitive to touch and craves more tactile stimulation, therapy might involve finger-painting, playing with shaving cream or rolling around in a bin of dried beans.

"With children, what we're doing is trying to normalize their everyday activities and routines by helping them respond normally to sensory input," Miller said. "That's something a lot of people don't understand. They think it's some kind of magic, that we're weaving spells or doing something they don't understand."

The goal behind DSI treatment, Miller said, is to improve the way kids respond to sensory stimuli so they can better deal with the world around them. "The theory of occupational therapy with a sensory integration framework proposes that we are making neurological changes. To the extent that changing behavior changes the brain -- I would say that's true. However, there's no empirical evidence that this type of occupational therapy directly changes any processes or mechanisms in the brain. That highlights the importance of doing research to uncover what, if anything, is being affected in the brain."

Length of treatment can vary widely, from several months to a few years; Balzer-Martin said six to eight months of weekly sessions is common. Insurance sometimes covers the care, particularly if a physician authorizes it, she said, but often parents end up paying, at a rate of approximately $90 an hour. This hefty out-of-pocket expense, combined with the lack of research proving the treatment effective, or identifying the mechanism by which it works, bothers some.

Martha Bridge Denckla, a professor of neurology and psychiatry at Johns Hopkins and the Kennedy Krieger Institute, said, "I don't see one piece of scientific evidence for the efficacy of treatment. We don't know enough to say, 'Oh, if we do this exercise or this intervention, we're going to rewire this nervous system in the right way.' We always rewire the nervous system whenever we teach anybody anything. But how do we know that this is the right way? What it boils down to is: We don't know whether these particular exercises and maneuvers are worth the time of the child and the money of the parents."

Yet some parents say their children have been transformed by DSI treatment. And this positive word of mouth, as much as anything, has encouraged other parents to seek treatment for their children's sensory integration problems.

"Occupational therapy has helped my son so much," Donna Kacin said of her son, who is now in kindergarten. "He adapts so much better to things that used to overwhelm his life -- transitions, crowds, loud noises. He's an incredibly happy kid now. If he starts to feel overwhelmed, he'll go and jump on the trampoline or do something that makes himself feel better. And our jobs as parents are much easier because we understand his behavior and how to respond to it better."

Resources

For more information about sensory integration dysfunction, consult the Sensory Integration Resource Center's Web site, which is run by The Children's Hospital of Denver, www.sinetwork.org.

Stacey Colino has written for many national magazines. This is her first story for The Washington Post Health section.

From Washingtonpost.com