Sensory Integration

Sensory Support for Development and Brain Function

Sensory input is necessary for optimal brain function. The brain is designed to constantly take in sensory information, and it malfunctions if deprived of it. Sensory deprivation experiments conducted in the 1950s and 1960s made it clear that without an adequate inflow of sensation, the brain generates its own input in the form of hallucinations and subsequently distorts incoming sensory stimuli.¹⁴⁵ If adequate sensory stimulation is not available at critical periods in development, brain abnormalities and resulting behavioral disorders result.^74,77,79 It is now well established that persistent, serious impairments in cognitive, social, and emotional functioning often result when infants and young children are institutionalized in environments that are impoverished with respect to availability of a wide range of sensory experiences, the presence of a nurturing caregiver, and opportunities for sensory-motor exploration.^29,47,56,122

Ayres considered sensory input to be sensory nourishment for the brain, just as food is nourishment for the body.¹⁸ Wilbarger, a colleague of Ayres, built on this concept with the sensory diet, designed to provide individualized sensory experiences for the child with sensory integrative dysfunction.¹⁵² The therapeutic sensory diet provides an optimal combination of sensory-based activities at the appropriate intensities for a specific child. For most typically developing children, the sensory diet does not require conscious monitoring by caregivers. The environment continuously “feeds” the child a variety of nourishing sensations in the flow of everyday life.

As critical as input is to the developing brain, the mere provision of sensory stimulation is limited in value. Too much stimulation can generate stress that is detrimental to brain development and may reduce the person’s subsequent ability to cope with stress.⁷² To have an optimal effect on development, learning, and behavior, the sensory input must be actively organized and used by the child to act on and respond to the environment.

Adaptive Response

A child does not passively absorb whatever sensations come along. Rather the child actively selects the sensations most useful at the time and organizes them in a fashion that facilitates accomplishing goals. This is the process of sensory integration. When this process is going well, the child organizes a successful, goal-directed action on the environment, which is called an adaptive response. When a child makes an adaptive response, he or she successfully meets some challenge presented in the environment. The adaptive response is possible because the brain has been able to efficiently organize incoming sensory information, which then provides a basis for action (Figure 11-1).

Adaptive responses are powerful forces that drive development forward. When a child makes an adaptive response that is more complex than any previously accomplished response, the brain attains a more organized state and its capacity for further sensory integration is enhanced. Thus, sensory integration leads to adaptive responses, which in turn result in sensory integration that is more efficient.

Ayres provides the example of learning to ride a bicycle to illustrate this process.¹⁸ The child must integrate sensations, particularly from the vestibular and proprioceptive systems, to learn how to balance on the bicycle. The senses must accurately and quickly detect when the child begins to fall. Eventually, perhaps after many trials of falling, the child integrates sensory information efficiently enough to make the appropriate weight shifts over the bicycle to maintain balance. This is an adaptive response, and once made, the child is able to balance more effectively on the next attempt to ride the bike. The child’s nervous system has changed, so the child is now more adept at bicycle riding.

In making adaptive responses, the child is an active doer, not a passive recipient. Adaptive responses come from within the child. No one can force a child to respond adaptively, although a situation may be set up that is likely to elicit adaptive responses from the child. For typically developing children and for most children with disabilities, there is an innate drive to develop sensory integration through adaptive responses. Ayres called this inner drive and speculated that it is generated primarily by the limbic system of the brain, a structure known to be critical in both motivation and memory.¹⁸ Ayres designed therapeutic activities and environments to engage the child’s inner drive (elicit adaptive responses) and, in so doing, advance sensory integrative development and the child’s occupational competence.

Neural Plasticity

It is thought that when a child makes an adaptive response, change occurs at a neuronal synaptic level. This change is a function of the brain’s neural plasticity. Plasticity is the ability of a structure and concomitant function to be changed gradually by its own ongoing activity.¹¹ It is well established in the neuroscientific literature that when organisms are permitted to explore interesting environments, significant increases in dendritic branching, synaptic connections, synaptic efficiency, and size of brain tissue result.⁷⁹ These changes are most dramatic in a young animal and probably represent a major mechanism of brain development,⁷⁴ although it is clear that such manifestations of plasticity are characteristic of optimal brain functioning throughout the lifespan.^27,55,88

Studies of the effects of enriched environments on animals indicate that the essential ingredient for positive brain changes is that the organism actively interacts with a meaningful and challenging environment.^31,79 Passive exposure to sensory stimulation does not produce these same positive changes.^55,59 It can be hypothesized from these findings that adaptive responses activate the brain’s neuroplastic capabilities. Furthermore, the brain’s plasticity makes it possible for an adaptive response to increase the efficiency of sensory integration at a neuronal level.

Central Nervous System Organization

Ayres looked to the organization of the central nervous system (CNS) for clues to how children organize and use sensory information and how sensory integration develops over time.¹¹ At the time that she was developing her theory, hierarchic models of the CNS dominated thinking in the neurosciences.

Hierarchic models view the nervous system in terms of vertically arranged levels, with the spinal cord at the bottom, the cerebral hemispheres at the top, and the brainstem sandwiched in between. These levels are interdependent yet reflect a trend of ascending control and specialization. Thus, the cerebral cortex at the top of the hierarchy is highly specialized and analyzes precise details of sensory information. Ordinarily the cortex assumes a directive role over lower levels of the hierarchy. For example, the cortex may command lower centers to “ignore” certain stimuli deemed unimportant. This process is called descending inhibition and is critical in enabling higher brain functions to work efficiently.¹¹ The lower levels of the CNS, however, have functions that are more diffuse and primitive, less specialized, and yet potentially more pervasive in influence compared with those of the higher levels. One of the important responsibilities of the lower levels is to filter and refine sensory information before relaying organized sensory messages upward to the cerebral cortex. Thus, cortical centers depend on lower centers for the receipt of essential, well-organized sensory information to analyze in preparation for the planning of action. According to hierarchic views, the higher levels of the CNS superimpose functions that are more sophisticated on the lower levels, but these do not replace the important lower level functions.¹¹

Ayres believed that critical aspects of sensory integration are seated in the lower levels of the CNS, particularly the brainstem and thalamus.¹¹ Most of the CNS processing of vestibular information occurs in the brainstem, and much somatosensory processing takes place there and in the thalamus. One of the basic tenets of Ayres’s theory is that, because of the dependence of higher CNS structures on lower structures, increased efficiency at the levels of the brainstem and thalamus enhance⁵ higher order functioning.¹¹ This view varies from traditional neuropsychology and education models, which have tended to emphasize the direct study and remediation of high-level, cortically directed skills such as reading and writing. However, newer models of education have considered “readiness” for academics and the importance of other modes such as “kinesthetic” learning.^60,141

In adopting a hierarchic view of the CNS, Ayres also assumed that the CNS develops hierarchically from bottom to top, with spinal and brainstem structures maturing before higher level centers.¹¹ At the time that Ayres was developing her theory, this was somewhat speculative, although generally accepted by neuroscientists. In research conducted in more recent years, the use of positron electron tomography (PET) scans on infants has provided direct support for the notion that brain development proceeds in a bottom-to-top direction.⁴⁸

The hierarchic approach to CNS functioning and development led Ayres to emphasize the more primitive vestibular and somatosensory systems in her work with young children. These systems mature early and are seated in the lower CNS centers (particularly the brainstem, cerebellum, and thalamus). Using the logic of hierarchy, Ayres reasoned that the refinement of primitive functions, such as postural control, balance, and tactile perception, provides a sensorimotor foundation for higher-order functions, such as academic ability, behavioral self-regulation, and complex motor skills (e.g., those required in sports). Thus, she viewed the developmental process as one in which primitive body-centered functions serve as building blocks upon which complex cognitive and social skills can be scaffolded. This view undergirds a basic premise of the therapy approach that she developed: enhancing lower-level functions related to the proximal senses might have a positive influence on higher-level functions.

On some points Ayres departed from a strictly hierarchic view of the CNS.¹¹ For example, she noted that each level of the CNS can function as a self-contained sensory integration system. Therefore, the brainstem can independently direct some sensorimotor patterns without being directed by the higher level cortex. Furthermore, the sensory integrative process involves the brain working as a whole, not simply as a series of hierarchically controlled messages, as rigid hierarchic models might suggest. These ideas are more consistent with the view of some contemporary biologists that the brain is a heterarchic system. A heterarchy is a system in which different parts may assume the controlling role in different situations; control does not always flow in a top-down direction.¹³⁵ Ayres was ahead of her time in suggesting that the brain does not operate exclusively as a hierarchy but has holistic characteristics. These heterarchic notions strengthened her view that functions considered primitive were worthy of serious consideration in therapy.

Prenatal Period

The first known responses to sensory stimuli occur early in life, at approximately 5½ weeks after conception.⁷⁸ These first responses are to tactile stimuli. Specifically, they involve reflexive avoidance reactions to a perioral stimulus (e.g., the embryo bends its head and upper trunk away from a light touch stimulus around the mouth). This is a primitive protective reaction. It is not until about 9 weeks’ gestational age that an approach response (moving of the head toward the chest) occurs,⁷⁸ probably as a function of proprioception.

The first known responses to vestibular input in the form of the Moro reflex also appear at about 9 weeks after conception. The fetus continues to develop a repertoire of reflexes such as rooting, sucking, Babkin, grasp, flexor withdrawal, Galant, neck righting, Moro, and positive supporting in utero that are fairly well established by the time of birth. Thus, when the time comes to leave the uterus, the newborn is well equipped with the capacity to form a strong bond with a caregiver and to actively participate in the critical occupation of nursing. These innate capacities require rudimentary aspects of sensory integration that are built into the nervous system. However, even in this earliest period of development, environmental influences, such as maternal stress, can have a significant impact on the quality of sensory integrative development. For example, Schneider and her colleagues found that infant rhesus monkeys born to mothers who had experienced stress in early pregnancy had signs of diminished responses to vestibular input, such as impaired righting responses, weak muscle tone, and attenuated postrotary nystagmus.^138,139

Neonatal Period

Touch, smell, and movement sensations are particularly important to the newborn infant, who uses these to maintain contact with a caregiver through nursing, nuzzling, and cuddling. Tactile sensations, especially, are critical in establishing a primary attachment relationship with a caregiver and fostering feelings of security in the infant. This is just the beginning of the important role that the tactile system plays in a person’s emotional life because it is directly involved in making physical contact with others (Figure 11-2). Proprioception is also critical in the mother–infant relationship, enabling the infant to mold to the adult caregiver’s body in a cuddly manner. The phasic movements of the infant’s limbs generate additional proprioceptive inputs. Together, all of these tactile and proprioceptive inputs set the stage for the eventual development of body scheme (the brain’s map of the body and how its parts interrelate).

The vestibular system is fully functional at birth, although refinement of its sensory integrative functions, particularly its integration with visual and proprioceptive systems, continues through childhood. Of all the sensory systems, the vestibular system is the first to mature.⁹⁸ Most caregivers who use rocking and carrying to soothe and calm the infant instinctively appreciate the influence of vestibular stimuli on the infant’s arousal level. Ayres pointed out that sensations such as these, which make a child contented and organized, tend to be integrating for the child’s nervous system.¹⁸

Experiences that activate the vestibular sense have other integrating effects on the infant as well. Being lifted into an upright position against the caregiver’s shoulder is known to increase alertness and visual pursuit.⁷⁰ While being held in such a position, the young infant’s vestibular system detects the pull of gravity and begins to stimulate the neck muscles to raise the head off the caregiver’s shoulder. This adaptive response reaches full maturation within 6 months. In the first month of life, head righting may be minimal and intermittent with much wobbling, but it will gradually stabilize and become firmly established as the baby assumes different positions (first when the baby lies in a prone position and later in the supine position).

The visual and auditory systems of the newborn are immature. The newborn orients to some visual and auditory inputs and is particularly interested in human faces and voices, although meaning is not yet attached to these sensations. Visually the infant is attracted to high-contrast stimuli, such as black-and-white designs, and the range of visual acuity for most stimuli is limited to approximately 10 inches. The infant’s visual acuity and responsiveness to visual patterns expand dramatically over the first few months of life.⁹⁸ During this time the infant begins to use eye contact to relate to the caregiver, further strengthening the bond between them.

Stimulation in each of the sensory systems potentially affects the infant’s state of arousal. The infant’s capacity to behaviorally adapt to changing sensations is another important aspect of sensory integrative development—the development of self-regulation. It is relatively easy to overstimulate young infants, for example, with changes in water temperature, changes in body position, or an increase in auditory or visual stimuli.¹³⁶ However, as sensory integration develops, the older child is better able to self-regulate his or her responses to changing stimuli by initiating behaviors that will be calming and soothing (such as thumb sucking or cuddling with a favorite blanket) or exciting and energizing (such as jumping or singing).¹²⁴ This process of self-regulation begins in the neonatal period and develops throughout early childhood.

First 6 Months

By 4 to 6 months of age, a shift occurs in the infant’s behavioral organization. The sensory systems have matured to the extent that the baby has much greater awareness and interest in the world, and developing vestibular-proprioceptive-visual connections provide the beginnings of postural control. During the first half of the first year, the infant begins to show a strong inner drive to rise up against gravity (Figure 11-3), and this drive is evident in much of the baby’s spontaneous play. Body positions during the first 6 months characteristically involve the prone position, with gradually increasing extension from the neck down through the trunk as the arms gradually bear more weight to help push the chest off the floor. By 6 months of age, many infants spend a great deal of time in the prone position with full active trunk extension, and most are able to sit independently, at least if propped with their own hands. These body positions usually are the infant’s preferred positions for play and are reflect the maturing of the lateral vestibulospinal tract. Head control is well established by 6 months of age and provides a stable base for control of eye muscles. This, of course, reflects the growing integration of vestibular, proprioceptive, and visual systems, which becomes increasingly important in providing a stable visual field as the baby becomes mobile.

Somatosensory achievements at this time are particularly evident in the infant’s hands. The infant uses tactile and proprioceptive sensations to grasp objects, albeit with primitive grasps. Touch and visual information are integrated as the baby begins to reach for and wave or bang objects. The infant has a strong inner drive to play with the hands by bringing them to midline while watching and touching them. Connections between the tactile and visual systems pave the way for later hand–eye coordination skills. Midline hand play is a significant milestone in the integration of sensations from the two sides of the body.

By now, neonatal reflexes no longer dominate behavior; the baby is beginning to exercise voluntary control over movements during play. The earliest episodes of motor planning occur as the infant works to produce novel actions. This becomes evident as the infant handles objects and begins to initiate transitions from one body position to another, as in rolling from prone position to supine. Although reflexes play a role in such actions (such as grasp and neck righting reflexes), the infant’s actions have a goal-directed, volitional quality and are not stereotypically reflex bound. The emergence of intentionality is a marker of the beginning of occupational engagement.

Second 6 Months

Another major transition occurs during the latter half of the first year. Infants become mobile in their environments, and by the first birthday they can willfully move from one place to another, many walking while others creep or crawl. These locomotor skills are the product of the many adaptive responses that have gone before, resulting in increasingly more sophisticated integration of somatosensory, vestibular, and visual inputs.

As the infant explores the environment, greater opportunities are generated for integrating a variety of complex sensations, particularly those responsible for developing body scheme and spatial perception. The child learns about environmental space and about the body’s relationship to external space through sensorimotor experiences.

During the second 6 months after birth, tactile perception becomes further refined and plays a critical role in the child’s developing hand skills. The infant relies on precise tactile feedback in developing a fine pincer grasp, which is used to pick up small objects. Proprioceptive information is also an important influence in developing manipulative skills, and now the baby experiments with objects using a variety of actions. These somatosensory-based adaptive responses contribute to development of motor planning ability. Further development of midline skills is also apparent as the baby easily transfers objects from one hand to the other and may occasionally cross the midline while holding an object.

Through the first year, auditory processing plays a significant role in the infant’s awareness of environment, especially the social environment. Auditory information is integrated with tactile and proprioceptive sensations in and around the mouth as the infant vocalizes. The fruits of this process begin to blossom in the latter half of this first year, when the infant begins to experiment with creating the sounds of the language used by caregivers. Vocalizations such as consonant–vowel repetitions (“baba” and “mamama”) are common. Parents often attach meaning to these infant vocalizations and strongly encourage them, thus leading the infant also to attach meaning to these sounds. By their first birthday, many infants have a small vocabulary of words or wordlike sounds that they use meaningfully to communicate desires to caregivers.

Another major landmark toward the end of the first year is beginning independence in self-feeding. This complex achievement requires refined somatosensory processing of information from the lips, the jaw, and inside the mouth to guide oral movements in the chewing and swallowing of food. Taste and smell sensations are also integral to this process, but self-feeding involves more than the mouth. All of the acquired sensory integrative milestones involving hand–eye coordination are important to self-feeding. The infant at this period of life uses the fingers directly to feed him or herself and to explore the textures of foods. At this stage, use of a utensil such as a spoon is not very functional and is messy because motor planning skills have not progressed to the point that the child can manipulate the utensil successfully. However, many infants begin to demonstrate a drive to use the spoon in self-feeding by the end of the first year. For many contemporary American infants, use of a spoon is the first real experience in using a tool (Figure 11-4).

The occupation of dining, then, begins to emerge in infancy as sensory integrative abilities mature, allowing the child to engage in self-feeding. As an occupation, dining in its fullest sense goes far beyond the physical, sensorimotor act of feeding. Dining usually takes place within a social context, whether at a family dinner at home or in a formal restaurant, so social standards for acceptable behavior and etiquette become increasingly important as the child develops. Furthermore, partaking in a meal and sharing certain types of food gradually come to take on powerful symbolic meanings. The sensory integrative underpinnings of the dining experience influence how the child experiences mealtimes and how others view the child as a dining partner, thus playing a role in shaping the social and symbolic aspects of this vitally important occupation.

Second Year

As the child moves into the second year, the basic vestibular-proprioceptive-visual connections that were laid down earlier continue to refine, resulting in growing finesse in balance and fluidity of dynamic postural control. Discrimination and localization of tactile sensations also become much more precise, allowing for further refinement of fine motor skills.

Increasingly complex somatosensory processing contributes to the continuing development of body scheme. Ayres hypothesized that as body scheme becomes more sophisticated, so does motor planning ability.¹¹ This is because the child draws on knowledge of how the body works to program novel actions (Figure 11-5). Throughout the second year, the typically developing toddler experiments with many variations in body movements. Imitation of the actions of others contributes further to the child’s movement repertoire. In experiencing new actions, the child generates new sensory experiences, thus building an elaborate base of information from which to plan future actions.

While motor planning ability becomes increasingly more complex in the second year, another aspect of praxis, ideation, begins to emerge. Ideation is the ability to conceptualize what to do in a given situation. Ideation is made possible by the cognitive ability to use symbols, first expressed gesturally and then vocally during the second year of life.³⁵ Symbolic functioning enables the child to engage in pretend actions and to imagine doing actions, even actions that the child has never before done. By the end of the second year, the toddler can join several pretend actions in a play sequence.¹⁰² Furthermore, the 2-year-old child demonstrates that he or she has a plan before performing an action sequence, either through a verbal announcement or through a search for a needed object.¹⁰² Thus, a surge in practic development occurs in the second year as the child generates many new ideas for actions and begins to plan actions in a systematic sequence.

The burgeoning of praxis abilities plays an important role in the development of self-concept. Infant psychiatrist Daniel Stern suggests that the sense of an integrated core self begins in infancy as an outcome of the volition and the proprioceptive feedback involved in motor planning.¹⁴⁷ The consequences of the child’s voluntary, planned actions add to the developing sense of self as an active agent in the world. As praxis takes giant leaps during the second year, so does this sense of self as an agent of power. The child feels in command of his or her own life when sensory integration allows the child to move freely and effectively through the world.¹⁸

Third through Seventh Years

The child’s competencies in the sensorimotor realm mature in the third through seventh years of life, which Ayres considered a crucial period for sensory integration because of the brain’s receptiveness to sensations and its capacity for organizing them at this time.¹⁸ This is the period when sensorimotor functions become consolidated as a foundation for higher intellectual abilities. Although further sensory integrative development can and usually does occur beyond the eighth birthday, the changes that take place are likely to be more limited than those that occurred earlier.

In the third through seventh years, children have strong inner drives to produce adaptive responses that not only meet complicated sensorimotor demands but also sometimes require interfacing with peers. The challenges posed by children’s games and play activities attest to this complexity. In the visual-motor realm, sophistication develops through involvement in crafts, drawing and painting, constructional play with blocks and other building toys, and video games (Figure 11-6). Children are driven to explore playground equipment by swinging, sliding, climbing, jumping, riding, pushing, pulling, and pumping. Toward the end of this period they enthusiastically grapple with the motor-planning challenges posed by games such as jump rope, jacks, marbles, and hopscotch. It is also during this period that children become expert with cultural tools such as scissors, pencils, zippers, buttons, forks and knives, pails, shovels, brooms, and rakes (Figure 11-7). Many children begin to participate in occupations that present sensorimotor challenges for years to come, such as soccer, softball, karate, gymnastics, playing a musical instrument, and ballet. Furthermore, children develop the ability to organize their behavior into more complex sequences over longer time frames. This makes it possible for them to become more autonomous in orchestrating daily routines, such as getting ready for school in the morning, completing homework and other school projects, and performing household chores.

As children participate in these occupations, they must frequently anticipate how to move in relation to changing environmental events by accurately timing and sequencing their actions.³⁹ This is particularly challenging in sports when peers, with their often unpredictable moves, are involved. Their bodies are challenged to maintain balance through dynamic changes in body position. In fine motor tasks, children must efficiently coordinate visual with somatosensory information to guide eye and hand movements with accuracy and precision while maintaining a stable postural base.

Children meet these challenges with varying degrees of success. Some are more talented than others with respect to sensory integrative abilities, but most children eventually achieve a degree of competency that allows them to fully participate in the daily occupations that they are expected to do and wish to do at home, in school, and in the community. Furthermore, most children experience feelings of satisfaction and self-efficacy as they master occupations that depend heavily on sensory integration.

1. Sensory modulation problems

2. Poor sensory discrimination and perception

3. Problems related to vestibular-proprioceptive functions

4. Difficulties related to praxis

Sensory Modulation Problems

Modulation refers to CNS regulation of its own activity.¹⁸ The term sensory modulation refers to the tendency to generate responses that are appropriately graded in relation to incoming sensory stimuli, rather than underreacting or overreacting to them. Cermak⁴⁵ and Royeen¹³¹ hypothesized that there is a continuum of sensory responsivity, with hyporesponsivity at one end and hyperresponsivity at the other. An optimal level of arousal and orientation lies in the center of the continuum (Figure 11-8). This is where most activity falls for most individuals, although everyone experiences fluctuations across this continuum of sensory responsivity in the course of a day. In the continuum model, dysfunction is indicated when the fluctuations within an individual are extreme or when an individual tends to function primarily at one extreme of the continuum or the other. The individual who tends to function at the extremely underresponsive end of the continuum may fail to notice sensory stimuli that would elicit the attention of most people. This characteristic often is identified as a problem in sensory registration. At a less severe degree of underresponsiveness, the individual notices sensory stimuli, but is slow to respond or seems to crave intense sensory input. At the opposite extreme of the continuum is the overresponsive individual with sensory defensiveness. This person is overwhelmed and overstressed by ordinary sensory stimuli.

Originally, Ayres thought of sensory registration problems as different in nature from sensory modulation problems such as tactile defensiveness.¹⁸ Soon after she introduced the concept of sensory registration, however, other experts in the field of sensory integration suggested that sensory registration and tactile defensiveness might be related through common underlying neural functions.^66,134 This idea contributed to the continuum model. Experts soon found that this simple continuum model did not adequately address the complexity of child behaviors, however. For example, Royeen and Lane hypothesized that the relationship between underresponsiveness and overresponsiveness may be circular instead of linear, because a child who is extremely defensive may be overloaded to the point of shutting down and becoming underresponsive.¹³⁴ Previously, we have criticized the continuum model as overly simplistic because sensory modulation very likely is influenced by the individual’s history of personal experiences and interpretation of the situation, as well as interactions among multiple neural systems.¹¹⁷ Furthermore, individuals who are unusually underresponsive to input from one sensory system may tend to be overresponsive in another system. For example, a child may be overresponsive to touch, but at the same time be underresponsive to vestibular sensations. The continuum model does not account for this phenomenon.

Dunn presented a conceptual model that takes into account the potential roles of various neural processes in generating patterns of underresponsiveness and overresponsiveness (Figure 11-9).^61,63 In her model, four main patterns represent individual differences in sensory responding: low registration, sensation seeking, sensitivity to stimuli, and sensation avoiding. Dunn hypothesized these patterns emerge from individual differences in the neural processes of habituation, sensitization, threshold, and maintenance of homeostasis. The person who falls in the low-registration quadrant of the model is underresponsive due to a high threshold for reactivity and therefore needs to have a high level of intensity in environmental stimuli in order to notice and attend. The person who falls in the sensation-seeking quadrant is also considered underresponsive with a high threshold but expresses this behaviorally by actively seeking out intense sensory input. The sensory sensitivity and sensation-avoiding quadrants represent overresponsive patterns. Individuals who fall in the sensory sensitivity quadrant have heightened awareness of, and are distracted by, sensory stimuli due to a low threshold, but they tend to passively cope with these sensations. In contrast, those who are sensation-avoiding not only have heightened awareness of sensory stimuli but actively attempt to avoid the ordinary sensations that they experience as noxious. One of the most important contributions of this model is that it can be used to consider what kinds of work and play or leisure environments present an optimal match for an individual’s sensory modulation characteristics.⁶³

In another model that addresses the complexity of sensory modulation, Miller, Reisman, McIntosh, and Simon differentiate between physiologic and behavioral elements of what they call sensory modulation disorders (SMDs).¹⁰⁷ Their ecologic model includes both external and internal dimensions affecting sensory modulation (Figure 11-10). External dimensions identified are culture, environment, relationships, and tasks, whereas internal dimensions are sensory processing, emotion, and attention. The external dimensions highlight the importance of context, whereas the internal dimensions focus on enduring differences among individuals. In this model, external and internal dimensions are interlinked through multidirectional, rather than linear, relationships and must be viewed together to design interventions for children with SMDs.

These models of sensory modulation help us to organize the complex information relevant to understanding children with difficulties in overresponding or underresponding to sensory information in everyday situations. Many unanswered questions about modulation remain. For example, some research indicates that many children frequently demonstrate behavioral characteristics of both underresponding and overresponding, often within the same sensory system.⁸⁶ This may be particularly the case for children with autism.^87,148 Existing models do not yet do an adequate job of explaining these phenomena. Nevertheless, these models are important because they provide a foundation upon which research programs can be built to explicate the complex issues that are involved. Today, research on patterns of sensory modulation and their manifestations in everyday activities is an area of focused investigation in occupational therapy.^28,67,107 In addition, the relationship between physiologic measures and patterns of behavior that characterize sensory modulation problems continues to be explored—for example, through studies of brain electrical activity⁵⁷ and autonomic responses^106,137 to sensory input.

Although there remains much to learn about sensory modulation, a general consensus exists among sensory integration experts regarding the behaviors that characterize different kinds of sensory modulation difficulties. These behaviors are described next.

Sensory Discrimination and Perception Problems

Sensory discrimination and perception allow for refined organization and interpretation of sensory stimuli. Some types of sensory integrative disorders involve inefficient or inaccurate organization of sensory information (e.g., difficulty differentiating one stimulus from another or difficulty perceiving the spatial or temporal relationships among stimuli). A classic example involving the visual system is that of the older child with a learning disability who persists in confusing a b with a d. A child with an auditory discrimination problem may be unable to distinguish between the sounds of the words doll and tall. A child with a tactile perception problem may not be able to distinguish between a square block and a hexagonal block using touch only, without visual cues.

Some children with perceptual problems have no difficulty with sensory modulation. However, modulation problems often coexist with perceptual problems. It makes sense that these two types of problems are associated. A child who often does not register stimuli probably has a deficit in perceptual skills because of a lack of experience interacting with sensory information. Conversely, the child who has sensory defensiveness may exert a lot of energy trying to avoid certain sensory experiences. Defensive reactions may make it difficult to attend to the detailed features of a stimulus and thereby may impede perception.

Discrimination or perception problems can occur in any sensory system. They are best detected by standardized tests, except in the case of proprioception, which is difficult to measure in a standardized manner. Discrimination or perception problems can occur in any sensory system. They are best detected by standardized tests, except in the case of proprioception, which is difficult to measure in a standardized manner. Although most factor analytic studies of the SIPT test scores revealed patterns that linked sensory perception with motor functions, certain patterns reflected specific sensory perception factors (e.g., a visual form and space perception factor or a tactile perception factor, as well as a somatosensory perception factor). Professionals in many fields, such as neuropsychology, special education, and speech language pathology, are trained to evaluate perceptual problems, and their focus usually is on the visual and auditory systems. In contrast, occupational therapists are unique in their understanding of the functional relevance of lesser known areas of sensory perception such as tactile, kinesthetic, and vestibular sensory processing.

Vestibular-Proprioceptive Problems

In her research, Ayres identified a pattern of problems thought to reflect inefficient central vestibular processing. Clinical signs related to this type of problem involve the motor functions that are outcomes of vestibular processing, such as poor equilibrium reactions and low muscle tone, particularly of the extensor muscles, which are strongly influenced by the vestibular system. These disorders are assessed using informal and formal clinical observations and standardized test scores.

Different names have been applied to vestibular processing problems at different points in time because of the changing patterns of research findings. In her early factor analytic studies, Ayres identified a linkage between postural-ocular mechanisms and integration of the two sides of the body. Clinically, she called the related dysfunction a disorder in postural and bilateral integration, and she noted that it often occurred in children with learning disabilities, especially those with reading disorders.¹¹ Additional problems commonly seen in this disorder include low muscle tone, immature righting and equilibrium reactions, poor right-left discrimination, and lack of clearly defined hand dominance.

Later in the 1970s, Ayres included the Southern California Postrotary Nystagmus Test (SCPNT) in her research as a more specific measure of vestibular processing.¹⁴ This test continues to be used and is part of the SIPT. Based on analysis of SCPNT scores, Ayres identified a vestibular processing component to the postural and bilateral integration (PBI) disorder.¹⁷ At this point she replaced the old PBI concept with the term vestibular-bilateral integration (VBI) disorder. One of the main characteristics of this problem was depressed postrotary nystagmus scores, suggesting inefficient central processing of vestibular input. Also characteristic were other signs of vestibular-related dysfunction, such as low muscle tone, postural-ocular deficits, and diminished balance and equilibrium reactions. In addition, poor bilateral coordination was implicated in VBI disorder.

Factor and cluster analyses using the SIPT led to further evolution of the concept of vestibular processing disorders. The SIPT studies identified a bilateral integration and sequencing (BIS) factor characterized by poor bilateral coordination and difficulty sequencing actions, which Ayres proposed was influenced primarily by vestibular functioning.²¹ Building on Ayres ideas, Fisher suggested that poor vestibular-proprioceptive processing is the basis for a type of sensory integrative dysfunction characterized by poor bilateral integration and sequencing.⁶⁸ She used the term vestibular-proprioceptive to emphasize that these two sensory systems work so closely together that their functions are intertwined.

In addition, Fisher introduced an interesting new concept in relation to the BIS pattern: the notion of projected action sequences.⁶⁸ To perform a projected action sequence, the child anticipates how to move as his or her spatial relationship to the environment changes, as when running to kick a ball or catching a moving ball. Fisher suggested that difficulty with projected action sequences is related to poor vestibular-proprioceptive processing, and, furthermore, that such deficits are a form of motor planning disorder. Thus, Fisher proposed a formal link between vestibular processing and praxis through the production of bilateral and sequenced movements.

Following Fisher’s work, other experts recently addressed the BIS pattern as a mild form of praxis disorder that generally is associated with vestibular-proprioceptive difficulties and characterized by problems with bilateral coordination as well as anticipatory actions.^39,85,125 These authors also acknowledged that there may be a subset of children with BIS problems who do not have sensory integrative difficulties, in much the same way that children with isolated visual or auditory perception problems are not thought to have a sensory integration disorder.

Despite the variety of ways that have been used to describe vestibular-proprioceptive problems, certain classic clinical signs are common to all. In general, many children with these problems do not have a severe level of dysfunction, so the problem is easy to overlook. These children often exhibit poor equilibrium reactions, lower than average muscle tone (particularly in extensor muscles), poor postural stability, a tendency toward slouching, and difficulty in keeping the head upright. Inefficiency of the vestibularocular pathways may adversely affect function in directing head and eye movements while moving, as when watching a rolling soccer ball while running to kick it. Impaired balance and equilibrium reactions are likely to affect competence in performing activities such as bicycle riding, roller-skating, skiing, and playing games like hopscotch. Poor bilateral integration interferes with these activities as well. In addition, poor bilateral integration makes activities such as cutting with scissors, buttoning a shirt, or doing jumping jacks especially challenging. Bilateral integration difficulties are sometimes manifested in delays in body midline skill development, such as hand preference, spontaneous crossing of the body midline, and right-left discrimination. Neural connections between the vestibular centers in the brainstem and the reticular activating system also put children with vestibular processing disorders at risk for problems with attention, organization of behavior, communication, and modulation of arousal.

Praxis Problems

Praxis is the ability to conceptualize, plan, and execute a nonhabitual motor act.¹⁸ Problems with praxis are often referred to as dyspraxia. When the term dyspraxia is used in regard to children, it usually refers to a condition characterized by difficulty with praxis that cannot be explained by a medical diagnosis or developmental disability and that occurs despite ordinary environmental opportunities for motor experiences. When Ayres originally wrote about dyspraxia, she used the term developmental apraxia.¹¹ However, because the term apraxia is often associated with brain damage in adults, she later replaced this term with developmental dyspraxia.^18,20 The prefix developmental implies that the condition emerges in early childhood development and is not the result of traumatic injury.

As noted previously, Ayres was struck with the relationship between tactile perception and praxis that emerged in study after study. She hypothesized that good tactile perception contributes to development of an accurate and precise body scheme, which serves as a reservoir of knowledge to be drawn on in planning new actions. Her interest in praxis appeared to grow over time, as is evident in the number of praxis tests included in the SIPT as opposed to the older SCSIT. When Ayres discussed praxis in relation to her SIPT studies, she introduced the idea that praxis problems may be manifested in different forms, not all of which are sensory integrative in nature.²¹ She coined the term somatopraxis to refer to the aspect of praxis that is sensory integrative in origin and grounded in somatosensory processing. At the same time she introduced the term somatodyspraxia to refer to a sensory integrative deficit that involves poor praxis and impaired tactile and proprioceptive processing. By definition, somatodyspraxia involves a disorder in tactile discrimination and perception. Cermak noted that not all children with developmental dyspraxia demonstrate poor tactile perception.⁴⁷ The term somatodyspraxia applies only to those who do.

The child with somatodyspraxia typically appears clumsy and awkward. Novel motor activities are performed with great difficulty and often result in failure. Transitioning from one body position to another or sequencing and timing the actions involved in a motor task may pose a great challenge. These children typically have difficulty relating their bodies to physical objects in environmental space. They often have difficulty accurately imitating actions of others. Directionality of movement may be disturbed, resulting in unintentional breakage of toys when the child forcefully pushes an object that should be pulled. Many of these children have difficulties with oral praxis, which may affect eating skills or speech articulation.

Some children with dyspraxia have problems with ideation (i.e., they have difficulty generating ideas of what to do in a novel situation). When asked to simply play, without being given specific directions, these children may not initiate any activity or they may initiate activity that is habitual and limited or seems to lack a goal. Typical responses may include are to wander aimlessly; to perform simple repetitive actions such as patting or pushing objects around; to randomly pile up objects with no apparent plan; or for the more sophisticated child, to wait to observe others doing an activity and then imitate them rather than initiating an activity independently. May-Benson expanded on the role of ideation in praxis, highlighting the role of language and the social environment and reviewing the neuroanatomic foundations for this important function.⁹⁹

For children with dyspraxia, skills that most children attain rather easily can be excessively challenging (e.g., donning a sweater, feeding oneself with utensils, writing the alphabet, jumping rope, completing a puzzle). These skills can be mastered only with high motivation on the part of the child, coupled with a great deal of practice, far more than most children require. Participation in sports is often embarrassing and frustrating, and organization of schoolwork may be a problem of particular concern. Children who have somatodyspraxia and are aware of their deficits often avoid difficult motor challenges and may attempt to gain control over such situations by assuming a directing or controlling role over others.

Praxis is best evaluated using the SIPT, which is sensitive to difficulties in this area. However, parent interview and informal observations provide critical pieces in the assessment process. These are essential in evaluating ideation because currently available standardized tests on large normative samples are extremely limited in their measurement of this aspect of praxis. The new Test of Ideational Praxis is promising as a standardized, objective means for assessing ideation.¹⁰⁰

Secondary Problems Related to Sensory Integrative Difficulties

As already shown, sensory integration difficulties often impose some limitation on the quality of the child’s participation in occupations that he or she wants or needs to do as a member of a family, classroom, or community. How others respond to the child’s struggles may have a powerful effect on the child’s developing competence. In addition, the child’s willingness to grapple with challenging experiences will influence his or her occupational life over the years.¹¹⁴ Unfortunately, a number of secondary problems often arise in conjunction with sensory integration problems. These secondary problems may actually have a more powerful impact on the child’s life outcomes than the original sensory integration difficulty. In some cases, what started out as a minor sensory integration difficulty can become magnified into a major barrier to life satisfaction. Following is an explanation of several of these indirect, but significant, influences on the child and family.

First, sensory integrative dysfunction is an “invisible” disability (i.e., not directly and easily detected by the casual observer) that is easily misinterpreted. Sensory integrative disorders can fluctuate in severity from one time to another within the same child. Moreover, the severity of dysfunction and the ways in which dysfunction is expressed vary tremendously from one individual to another. This variability makes it difficult to predict which situations cause problems for a particular child, how much discomfort results, and when distress is likely to occur. Parents and teachers of children with these disorders often find the unpredictability of the child’s behavior to be frustrating and difficult to understand. As a result, sensory integrative problems are frequently misinterpreted as purely behavioral or psychological issues. Consequently, the child may be punished or responded to inappropriately, which may lead to chronic feelings of hopelessness as the child develops a self-view as bad or incapable.

A second indirect effect of sensory integrative dysfunction on the child’s life is its negative influence on skill development secondary to limited participation in childhood occupations. The child who avoids finger painting because of tactile defensiveness or who rarely attempts climbing on the jungle gym because of dyspraxia misses more than these singular experiences. The child also misses experiences that hone underlying functions such as tactile discrimination, hand strength and dexterity, shoulder stability, balance and equilibrium, hand-eye coordination, bilateral coordination, ideation, and motor planning. If the child misses a substantial amount of such experiences over time, the gap between the child’s sensorimotor skills and the skills of peers may grow.

In addition to interference with the development of sensorimotor functions, interactions important to the development of communication and social skills may not occur. Thus, some children with sensory integrative disorders may lack the ability to play successfully with peers partly because they have not been able to participate fully in the play occupations in which sensory, motor, cognitive, and social skills emerge and develop. The fear, anxiety, or discomfort that accompanies many everyday situations is also likely to work against the expression of the child’s inner drive toward growth-inducing experiences. Therefore lack of experience and diminished drive to participate compound the direct effects of a sensory integrative disorder. Consequently, the development of competence in many domains of development may be seriously compromised.

A third indirect effect of sensory integrative problems is the undermining of self-esteem and self-confidence over time. Children with sensory integrative problems are often aware of their struggles with commonplace tasks, so it is natural for them to react with frustration. Frustration is likely to mount as the child observes peers mastering these same tasks effortlessly. Chronic frustration can negatively affect and detract from the child’s feelings of self-efficacy. Instead, the child may develop feelings of helplessness. This leads to further limitations in the child’s experiences because the child becomes less likely to attempt challenging activities.

Interviews and Questionnaires

The need for an occupational therapy assessment of sensory integration usually arises when a parent, teacher, physician, or other person who knows the child notices problems that the child is experiencing that are not easily explained by other conditions or considerations. The referral source, family members, and others who work with the child may all be valuable sources of information through interview or questionnaire (Figure 11-11). This initial phase of evaluation identifies the presenting problems, or main concerns, about the child and begins the process of determining whether sensory integration difficulties might account for the concerns about the child.

The initial interview with the parent, teacher, or other referral source provides an opportunity for the therapist to gather important information about signs of sensory integration problems that may be present. For example, the teacher may report that the child is always fighting while standing in line and cannot seem to stay seated during reading circle time. Further questioning by the therapist may disclose signs of tactile defensiveness that might explain the child’s behavior but were not considered by the teacher, who is unfamiliar with this condition. A parent may be able to provide critical information about the child’s development, which may be helpful in identifying early signs of sensory integrative dysfunction. For instance, parents may have noticed that specific tasks, such as cutting with scissors or pedaling a tricycle, were especially difficult for the child. Since difficulty coordinating the two sides of the body is common when vestibular processing difficulties are present, this type of information can inform the therapist about additional observations and tests needed. Another important role of the interview is to uncover alternative explanations of the child’s difficulties that may rule out sensory integration problems, such as when a recent emotional crisis (e.g., a divorce or death) coincides with the onset of problems. Miller and Summers provided examples of the kinds of questions to ask in a parent interview.¹⁰⁸

Questionnaires, checklists, and histories given by caregivers and other adults who know the child well are other means for gathering information that aid in identifying presenting problems, estimating how long they have been a concern, and clarifying the priorities of the family. One such instrument is a sensory history or similar questionnaire. Originally developed by Ayres as an unpublished questionnaire, this type of instrument asks parents questions regarding specific child behaviors indicative of sensory integrative dysfunction, and parents respond by rating the child using a Likert-style scale. These types of questionnaires were subsequently developed using normative samples to produce reliable and valid scores. The Sensory Profile⁶² and the Sensory Processing Measure (SPM)¹¹⁶ are two sensory questionnaires used extensively in pediatric occupational therapy. The Sensory Profile is available in versions for parents of infants and toddlers⁶⁴ and of children in early and middle childhood,⁶² as well as for self-reports of adolescents and adults.³⁶ Additionally, a Sensory Profile School Companion is available for teacher report of child behavior at school.⁶⁵ The SPM has two forms, Home¹¹⁵ and Main Classroom,¹⁰⁹ that are standardized on the same sample of 5- to 12-year-old children and can furnish a score that aids the therapist in discerning whether a child’s sensory issues are manifested differently in the contexts of home versus school. In addition, the SPM contains separate rating scales for school personnel other than the main teacher, such as art teacher, music teacher, or bus driver.

An additional way to gather information in the initial phases of assessment is through review of records, including previous reports from other professionals as well as educational and medical histories. It is useful to talk with the child directly when possible. Royeen and Fortune developed a child questionnaire for the assessment of tactile defensiveness, called the Touch Inventory for Elementary School–Aged Children (TIE).^133,134 Children with sufficient verbal skills to discuss their own abilities, perceptions, and difficulties can sometimes provide invaluable insight into their condition through such a questionnaire-based interview. The Alert Program, a group intervention program for older children and adults, includes a self-assessment of sensory preferences that can be adapted for assessment of younger children to help them identify and communicate their characteristic sensory responses.¹⁵⁴

The information garnered through the initial interview process is used to decide whether further assessment is warranted and, if so, which evaluation procedures are most appropriate. This information is also critical in interpreting the final pool of information gathered through assessment and in prioritizing goals for the child in light of the main concerns of the family.

Informal and Formal Observations of the Child

Direct observation of the child is essential to the evaluation of sensory integration. Informal observations, clinical observations, and standardized testing are commonly used.

Standardized Testing

Occupational therapists frequently use standardized tests to evaluate sensory integration. Although several tests are available that contribute incidental information regarding sensory integrative functions, the SIPT protocol is the only set of standardized tests designed specifically for in-depth evaluation of sensory integration. The SIPT evolved from a series of tests that Ayres developed in the 1960s^3,4,6,7,18 and later published as the SCSIT¹² and the SCPNT.¹⁴ The standardization process used in the development of the SIPT was rigorous, involving normative data on approximately 2000 children in North America and extensive reliability and validity studies.²¹ Its 17 tests measure tactile, vestibular, and proprioceptive sensory processing; form and space perception and visuomotor coordination; bilateral integration and sequencing abilities; and praxis.²⁵ A list of the 17 tests and the functions measured by each is presented in Table 11-3.

The SIPT protocol requires about 1½ to 2 hours to administer and another 30 to 45 minutes to score. Raw scores may be translated into standard scores by the therapist using a computer diskette available from the publisher. Alternatively, raw scores may be sent to the publisher, Western Psychological Services, for an analysis using the normative data. After normative scores are obtained, the therapist critically examines them to determine if patterns of sensory integrative dysfunction are evident. Not only are patterns of test scores scrutinized, but also the therapist’s observations of child behavior during testing are considered in interpreting test scores. Finally, test scores and test behaviors are integrated with all other sources of information from the assessment in reaching a conclusion regarding the status of sensory integrative functioning.

Like all standardized tests, the SIPT protocol is administered with adherence to standardized procedures (Figure 11-12). Specialized training is required for administration and interpretation. This tool is a complex set of tests and, unlike most published tests, cannot be self-taught by simply reading the manual. In addition to formal training for the SIPT, it is strongly recommended that therapists practice administration of the tests with children who do not have any known problems and with children who have recognized difficulties. With this experience and training, the therapist can administer the tests in a manner that produces reliable scores while allowing for observation of behaviors that provide additional information about the child’s sensory integration and praxis abilities.

Other pediatric tests include items or subtests from which inferences regarding sensory integration may be drawn. For example, the Miller Function & Participation Scales includes tests of praxis, visual-motor integration, figure–ground perception, and some vestibular functions.¹⁰⁴ A number of tests, such as the Bruininks-Oseretsky Test of Motor Proficiency, (BOT-2),³⁷ measure aspects of fine and gross motor skills (such as bilateral coordination) that are related to sensory integrative functions. Other tests, such as the Developmental Test of Visual Motor Integration,³⁰ provide specific information related to visual-perceptual and perceptual-motor skills.

Some tests geared toward the broader evaluation of occupation, such as the School Function Assessment (SFA)⁵⁴ or the Social Participation Scale of the SPM,¹¹⁶ are useful for identifying the extent to which sensory integrative disorders may be affecting the child’s participation in occupations within specific settings. For the child with suspected sensory integrative problems, tests such as the SFA are most effectively used along with specific measures of sensory integration. When combined, these tests identify the functional problems to target in intervention and the reasons for the child’s difficulties.

Consideration of Available Services and Resources

In addition to the information that is gathered about the child, an occupational therapy assessment of sensory integration takes into consideration the services and resources that are available to the child and family. Information regarding the type of services that the child is currently receiving, how he or she is responding to these services, and what services, programs, and resources are available to the child need careful consideration in light of the purpose and findings of the evaluation before recommendations can be formulated. For example, an occupational therapist may be asked to provide a reevaluation of a child who has been receiving occupational therapy for several years. If the child continues to demonstrate significant sensory integrative problems and has shown a diminishing response to treatment using a sensory integration approach, the recommendations would be different from those for a child no longer showed evidence of a significant sensory integrative problem.

Similarly, a child who lives in an area where no occupational therapists are qualified to provide sensory integration intervention needs a different program recommendation from that for a child who has easy access to this type of service. Understanding family aspirations and values, as well as resources, such as funding, transportation, time, and caregivers, is also critical in identifying the types of services that will be most helpful to the child and family. These issues are as important to the assessment process as the child factors that are addressed in a sensory integration evaluation.

Interpretation of Assessment Findings

Once all of the information from interviews, questionnaires, informal and formal observations, standardized tests, and consideration of available services and resources has been collected, the occupational therapist must integrate and interpret these data to reach meaningful conclusions and appropriate recommendations for the individual child. Conclusions and recommendations are framed with an overriding consideration of the occupations of the child and family and the contexts that influence occupational engagement.^1,127 Burke, Schaaf, and Hall advocate the strategy of creating a narrative, or story, to form an integrated understanding of the child and family in order to focus assessment and intervention planning on issues that are most meaningful and important to them.⁴⁰ In using such a future-oriented, top-down approach, the therapist not only generates a picture of the child and family in the present, but also imagines how changes might unfold over the next few years.¹¹⁴ Therapists use research as well as training and experience to formulate conclusions and recommendations. (See Research Note 11-1 for an example of research that can inform interpretation of how assessment data relate to a child’s academic functioning in school.)

One of the important steps in interpretation of assessment findings is to evaluate whether a sensory integrative problem may contribute to the occupational challenges of the child. To do this, data are classified into categories that either support or refute the presence of particular types of sensory integrative problems. After a detailed analysis of the constellation of assessment findings, a hypothesis is generated as to whether a sensory integrative problem appears to be present and, if so, what type it appears to be.

As in any aspect of occupational therapy, it is critical to relate the assessment findings to the presenting problems and initial concerns of the family or referral source. For example, an assessment may uncover signs of tactile defensiveness in a child described by the parents as destructive and impulsive. The evaluating therapist explains how tactile defensiveness may be related to the child’s behavior problems. Because sensory integrative problems are not always recognized and understood, the therapist includes an explanation of how the assessment findings are linked to the daily life experiences and occupations of the child and family.⁹⁴

If an assessment leads to a recommendation for intervention, it generally includes an estimate of the duration of time that the child should receive therapy, some indication of prognosis, and a statement regarding expected areas of change. The anticipated gains can be further clarified through the establishment of specific goals and objectives. Writing and explaining goals will provide the occupational therapist with an opportunity to illuminate the ways in which the identified sensory integration issues intersect with the presenting problems and desired functional outcomes.⁹⁴ Regardless of the types of goals that are written, goals are established in a manner that is culturally relevant for the family and considers the needs and wishes of the individual child.

The format in which goals are specified is often a function of the setting in which therapy is delivered. For example, a school district may include certain types of goals as part of an individualized education plan, whereas a hospital setting may require medically related outcomes. Goal attainment scaling is a specific method for writing goals that are individualized and then quantified to allow for comparison of outcomes across a large group of children.⁹⁵ In this process, individualized goals are carefully placed on a standard scale that allows for quantitative comparison of changes across dissimilar outcomes (e.g., the amount of change in pumping a swing in comparison with the amount of change in tolerance of food textures). Although this method was developed for outcomes research, it may be useful in documenting intervention effectiveness across a large group of children for purposes of program evaluation.