Tactile Defensiveness and Other Sensory Modulation Difficulties
Catherine Watson Genna, BS, IBCLC
New York City, New York, USA
From: LEAVEN, Vol. 37 No. 3, June-July 2001, pp. 51-53
Tactile defensiveness is a sensory modulation difficulty that results in an inability to tolerate touch stimulation. Infants who exhibit tactile defensiveness will often arch away from contact, have difficulty feeding, and have great difficulty in self-regulation. Conversely, they may insist on being held constantly, screaming if put down. Parents may suspect that something is unusual about their child's behavior, but since the signs of sensory modulation problems are subtle, the child may go undiagnosed for years.
Dysfunction in Sensory Integration (DSI)
Tactile defensiveness is rarely the only sensory processing or modulation issue in an individual; it is usually a component of a wider dysfunction in sensory integration. Sensory integration is the ability of the brain to take in, combine, and organize sensory information so that it can be interpreted and acted upon. Sensory modulation is the ability to filter or attend selectively to sensory information, in other words, to pay less attention to unimportant things like the feeling of your clothes on your body and more attention to important things like the traffic in the street you are crossing. Sensory modulation typically improves as children mature. Children with poor sensory modulation may be over (hypersensitive) or under (hyposensitive) reactive to sensation. It is not unusual to be hypersensitive to some senses, and hyposensitive to others.
In addition to vision (sight), auditory (hearing), gustatory (taste), olfactory (smell), and tactile (touch) systems that are familiar to most people, humans also rely on the vestibular system. The vestibular system senses head position in relation to gravity using the semicircular canals of the inner ear and the proprioceptive-kinesthetic system, which uses muscle stretch receptors (proprioceptors) to give information about the body's position in space (kinesthesia). Together, the vestibular, proprioceptive, and kinesthetic sense systems give rise to the body schema, or a mental picture of the shape and position of the body.
Children with dysfunction in sensory integration often have delayed speech and motor (physical skills) development, because of the inadequate feedback from their muscles, which makes it much more difficult for them to develop an accurate body schema. Imagine trying to learn to pronounce the new sounds of a foreign language while your mouth is numb from Novocain (dental anesthesia)!
Another important component of sensory integration is discrimination. Sensory discrimination is the ability to notice small differences in sensations. A child with poor tactile discrimination may have difficulty with fine motor skills. Trying to learn to use your hands when touch information is not well defined is similar to trying to pick up a small coin while wearing thick mittens.
Breastfeeding and DSI
A Leader's first contact with the mother of an infant with sensory modulation problems will likely be over feeding issues. Depending on the severity of the baby's feeding problems, the Leader might be able to assist the mother, or she might need to refer the mother to a lactation consultant for the feeding issues and continue giving the mother support.
Feeding difficulties for infants with tactile defensiveness may include a hyperactive gag reflex that makes it uncomfortable for the baby to draw the nipple deeply enough into his mouth to breasted effectively, and poor sucking quality and rhythmicity due to poor tactile discrimination. Oral muscle tone is usually low in children with DSI, and overall hypotonia (low muscle tone) may also be present due to underactivation of the muscles by the brain. The infant must work harder to use low tone muscles, therefore feeding is more of an effort. The baby may take much longer to breastfeed because of the poor timing of sucking bursts and the need for long rests. If feeding is inefficient, he will also need to feed frequently to get enough milk.
If the baby has low muscle tone, it might help to swaddle him loosely with his arms drawn across his chest and his legs drawn up toward his belly for feedings. Firm touch is usually far more tolerable to a tactile defensive infant than light touch. If the baby hates to be held, perhaps he will tolerate being held in a sling to nurse, or he might need to have his legs and belly angled away from mother's trunk on a firm pillow, with just his shoulders and head supported at the breast.
Breastfed babies with DSI seem to work unusually hard. By the end of a feeding, their hair may be soaked with sweat, partly due to the effort of feeding, and partly because control of autonomic (involuntary) functions is also poor. If the nursling has a hard time discriminating various sensations in the mouth, he may have a hard time transitioning from rooting to sucking. If this is the case, and the baby tolerates touch to the mouth and face, the mother might gently rub the baby's lips and the outer surface of the gums immediately before feeding to help him get ready. If the baby does not tolerate touch at all, being swung in a blanket swing from head to toe (rather than from side to side) providing linear vestibular stimulation may increase the baby's organization and improve muscle tone. A blanket swing is a low-tech device that runs on parent power. A strong, soft blanket is placed on a soft surface, baby is placed in the center of the blanket, the edges are drawn up over baby, and the parent holds the edges of the blanket tightly and gently swings baby for a few minutes. This simple intervention can have dramatic effects, and is less scary to the child with tactile defensiveness than a mechanical swing.
Babies with DSI may also have difficulty with the mechanics of sucking. Decreased awareness of the tongue may lead to difficulty using it properly to propel milk from the milk sinuses under the areola toward the nipple then onto the back half of the tongue; then form the milk into a small pool or bolus, and transport the bolus toward the throat for swallowing. If the tongue does not have the tone, strength, or range of motion to lift and press the breast against the palate (roof of the mouth), the baby might compensate by pressing more with his jaws. This excessive compression is painful for the mother. Getting a deeper latch, making sure the baby is not tongue-tied, and using an asymmetrical latch (see photos at left) to increase the amount of tongue in contact with the breast can all be helpful to reduce compression. If the baby tolerates touch to the tongue, the mother might "walk back on the tongue" immediately before feeding, or in the middle of a feeding if the baby increases compression due to tongue fatigue. Walking back on the tongue consists of providing a firm, vibratory stimulus with a fingertip on the tongue tip, then repeating it slightly farther back until just before the area that would trigger the baby's gag reflex. Vibration is a small amplitude, high frequency stimulus, in other words, the fingertip wiggles, moving very slightly but very quickly on each spot on the tongue.
Feeding the Older Child with DSI
When modulation of sensory input is deficient, the input might be perceived as more or less intense than it actually is. Children who are hyposensitive are usually messy eaters, as they have a hard time finding their mouths with the food, and their tongue has difficulty moving the food to the teeth and back to the tongue for a swallow. They typically overstuff their mouths, because they do not notice the sensation of fullness until the muscles are very stretched. It can be difficult for hyposensitive children to know when to swallow, and they may chew food far longer than necessary. Overstuffing the mouth can make it even harder to safely control the food in the mouth, and the child may gag or choke often. The child may not seem to notice soft foods at all, and may greatly prefer hard and crunchy foods, again because they provide more stimulation.
Children with tactile defensiveness often refuse solids, or foods with particular textures, tastes, and smells. They may run from the kitchen when a can of tuna is opened, complaining about the smell, and retreat to the far end of the home for hours. They may lean to use cutlery very early, out of reluctance to feel food on the hands. They may use many napkins at a meal trying to keep food particles away from the hands and face. They may even pick up finger foods with a fork, spoon, or napkin to avoid touching them.
Children with any type of DSI often hate mixed-phase foods, such as commercial "junior" foods with small chunks, or stews and soups that combine liquids and solids. This may be because the different thicknesses and textures need to be handled simultaneously in different ways in the mouth: the liquid needs to be swallowed while the solids are held on the tongue for later chewing. This can be impossible for a child who has difficulty handling even one texture at a time. When served mixed-phase foods, older children with DSI will typically separate out the ingredients on their plate, and eat all of one food, then all of another. This can be emotionally difficult for the family when visiting, as the child may be teased for "being a baby" or "playing with food" and the parents criticized for allowing this behavior. Even when DSI has been diagnosed, it can be difficult for the parents to make relatives understand the child's needs. It's even harder when the parent cannot explain why the child needs to eat in an unusual manner.
Psychosocial Aspects of Sensory Modulation Issues
A mother might have strong feelings of rejection if her baby arches away from her body when she holds him, averts his eyes from her, or falls to respond to her at all. Leaders can be empathetic to the mother's feelings while reframing her perceptions in terms of the infant's needs and tolerance of touch. The Leader can also help brainstorm ways that the baby might prefer being held. Some babies with DSI prefer being held facing away from mother, others prefer the firm containment of a baby sling, or the reduced contact of a backpack carrier. Some babies like to be held but have difficulty tolerating movement. These babies may be gravitationally insecure or have hypersensitive vestibular systems. Speaking to them before touching them, holding their heads firmly, and moving them slowly and gradually may help them tolerate movement.
Developmental delays are terrifying and confusing to parents. Children with DSI-related speech delays may learn to communicate in other ways, for example, by gesturing or consistently using nonword sounds (jargon). Relatives may criticize the parents for responding to this communication and not requiring the child to talk and may blame the speech delay on this responsiveness. Leaders can reassure parents that children have a drive to develop skills, and that responding to their nonverbal efforts reinforces the desire to communicate. Similarly, when children do not walk when expected, the parent is often blamed for carrying the child too much, when the parent is simply caring for the nonambulatory child appropriately. Leaders can point out the difference between providing opportunities for the child to practice and develop skills and frustrating the child by demanding the impossible. Parents of children with tactile defensiveness quickly learn that the child finds it impossible to tolerate tags in the clothing or synthetic fabrics. Leaders can reassure mothers that it is not spoiling their child to remove scratchy tags and dress the child in cotton, which is usually the preferred fabric.
If the brain fails to make sense of incoming sensations, it cannot formulate an appropriate response to the environment. Therefore, behavior of children with DSI is often rigid and stereotyped. Their need for structure and consistency far exceeds that of typical children. They may become fixated on unusual things. They might insist on repeating a few lines of dialogue from a favorite book or play many times a day, or insist on wearing only green clothing. It's as if the transmission in the child's brain is stuck and does not want to shift gears. While similar behaviors are seen in almost all children, they are unusually frequent, long-lived, and intense in children with DSI. Children with altered sensory modulation have great difficulty transitioning from one activity to another. Rituals such as saying good-bye to all the playground equipment before leaving, and talking about which activity is coming next can be helpful in easing transitions. Carrying a firm toy that fits in the hand can provide a deep touch stimulus that can help keep a child's nervous system organized in a stressful environment. Three-inch-long vinyl baby animals are a particular favorite for this purpose.
Environmental alterations increase stress, particularly in the defensive individual, and stress increases sensitivity to tactile sensations. Children with poor sensory modulation become overwhelmed easily by their world. This can be particularly difficult for the family when an outing or special occasion arises. The event that was meant to be fun can be very stressful for the child with DSI. The proximity of many bodies increases the chance for accidental light touch, which is most aversive and terrifying to the child with tactile defensiveness. An increase in noise from cheering crowds or amplified sound will overwhelm a child with auditory processing difficulties. Such a child may cover his ears with his hands and cry, scream, or make nonsense sounds to cover up the intolerable outside noise. A child with visual hypersensitivity may cringe at the variety of sights, and he may squint or close his eyes to feel safe. Waiting in lines (queues) proves particularly intolerable for children with sensory modulation difficulties. When children express their distress, parents may feel embarrassed, particularly if onlookers seem judgmental. Since DSI is an invisible disability, it does not elicit compassionate and tolerant social responses. Families may become hesitant to venture out, and many become isolated. Helping Group members understand the child's special needs may make it more comfortable for the mother to attend LLL meetings.
Children who have difficulty with the tactile and proprioceptive-kinesthetic systems will usually try to compensate for their poor idea of where their body is in space by using vision to guide their actions. They may be very clumsy, and fall often, because their vestibular system does not react in time to correct their balance. The tiniest crack in the sidewalk seems like a crater, and the child often overcompensates by lifting the foot very high. This overcompensation may be a manifestation of dyspraxia, a motor planning deficiency. Motor planning is the ability to conceive of, plan, and execute a novel task. Children with poor motor planning have difficulty using skills they already have in a new environment. A new street to walk down seems like an obstacle course to the child with dyspraxia; getting into an unfamiliar van may take five minutes of maneuvering. Patience is required of everyone who must wait for the child to figure out just how to get both legs safely over the engine hump and into the back seat.
Helping Parents Find Information
Children are by definition immature and have some difficulty with sensory modulation. Sensory modulation should improve as children grow. Children with dysfunction in sensory integration show their distress in the unusual intensity, frequency, and duration of their responses to sensation. If these responses prevent the child from participating in age appropriate activities (if the child refuses to walk on or touch the sand, for example, and cries on the blanket while the other children build sandcastles), if the child is frequently frustrated, or the discrepancy between a child's behavior and development and that of his peers seems to be increasing, the child may need to be evaluated. Occupational and physical therapists are the appropriate professionals to evaluate a child's sensory integration, particularly those certified in Sensory Integration (SI). Often, the child's physician must make the referral to the therapist. The mother may be able to request an early intervention evaluation herself if her child is under two or three years old. In infants, indications for early intervention referral may include feeding difficulties, disorganized behavior (constant crying or difficulty sleeping more than a few minutes at a time), unusual irritability, and unusual posturing. Occupational therapists make the diagnosis of sensory integration dysfunction by combining information from observations of the child with that from parent questionnaires and formal testing.
While it is not appropriate for LLL Leaders to make diagnoses, it is proper to refer parents to sources of information. This needs to be done with extreme caution and sensitivity, as even if parents are convinced there is something unusual about their child, they are usually not happy about having that feeling confirmed. After active listening to a mother's concerns about her child, the Leader might recommend a book or Web site from the Resources list for the mother to see if the information there fits her child. Leaders may also help the mother rehearse talking to the physician about her concerns. The mother will continue to require support through the stressful evaluation process and adjusting to the child's diagnosis. The warmth and acceptance of her LLL Group and Leader can be invaluable assets to the mother coping with a special needs child.
Catherine Watson Genna is an LLL Leader on Reserve status and a lactation consultant. She has a private practice in Queens County, New York, USA where she resides with her husband, David, and their children Vincent and Alyssa. She is grateful that Vinny's sensory integration dysfunction was the catalyst for her interest in infant sucking skills; that his occupational and physical therapists were generous with their knowledge; and that LLL was there to encourage her to meet his needs.
Audio tapes Making Sense of Sensory Integration, 1998; Belle Curve Records, Inc. PO Box 18387, Boulder, Colorado 80308-1387 USA. Audio cassette and booklet set, Mary Darlington, 1-888-357-5867.
www.childrensdisabilities.info/sensory_integration/index.html Hints for parents by parents of children with DSI.
www.sinetwork.org/ Information and resources for parents, teachers, and therapists.
home.ptd.net/~binelson/#SID/ Sandra Nelson's website on sensory integration, includes an article she wrote explaining DSI, and resources for other parents. [Editor's note: now at mywebpages.comcast.net/momtofive/SIDWEBPAGE2.htm]
www.tsbvi.edu/Outreach/seehear/fall97/sensory.htm An article and links on SI Dysfunction in Young Children.
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Creger, P., ed. Developmental Interventions for Preterm and High-Risk Infants. Therapy Skill Builders, 1995.
Dowling, D., Danner, S., and Coffey, P. Breastfeeding the Infant with Special Needs. New York, March of Dimes Birth Defects Foundation, 1997.
Fisher, A., Murray E., Bundy, A., eds. Sensory Integration: Theory and Practice. Philadelphia, F.A. Davis, 1991.
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Wolf, L. and Glass, R. Feeding and Swallowing Disorders in Infancy: Assessment and Management. San Antonio, Therapy Skill Builders, 1992.