When most people hear Sensory Processing Disorder (SPD), they tend to think of the child who cannot tolerate tags on clothes, covers their ears and screams at parades, and who pulls away from hugs at family parties. While these are all behaviors associated with SPD, they only align with one type.
Hypersensitivity, or sensory defensiveness, occurs when a child has difficulty filtering unnecessary sensory input and therefore gets bombarded with a waterfall of input, overflowing his or her regulatory system. However, there is another side to the story that often surprises parents that I work with. Just like a child may be over-sensitive, they may also be under. Poor sensory registration, or hypo-sensitivity, is another common classification of sensory processing disorder and applies to children who do not absorb, or register, all of the input entering their body. They are therefore “missing out” on crucial information from their own body and the environment, which is used to make adaptive responses and learn.
Imagine a giant waterfall, filling a pool at the bottom to the “just right” level. Now imagine that waterfall has a giant strainer at the bottom, causing a tiny fraction of the water to pass through and barely filling the pool. While typically processing children naturally and efficiently take in information from the environment through their many sensory receptors and use this information to make adaptive responses, this is much more difficult for children who miss some of the information coming in. Using the waterfall metaphor again, think how much more water you would need to send through the strainer to fill up the pool. This explains why poor sensory registration is often (but not always!) associated with “sensory seeking” behaviors, as children attempt to obtain additional input so that they may better absorb it. These seeking behaviors can often be misperceived as having difficulty following directions or misbehaving, while children may actually be trying to “fill their pool.” Another possible presentation is that children might appear to “be in la la land” and are likely not noticing or absorbing the cues they need to respond appropriately.
While it is very important to identify poor sensory registration, it can be difficult to identify at times.
Below you will find 10 red flags for poor sensory registration, organized by sensory system, to help you identify potential sensory processing deficits in your child:
Touch (Tactile) Processing:
- Your child does not notice when his or her face has food, toothpaste, or other materials on it. He or she may not be registering that input and will not notice unless pointed out by someone else or by looking in a mirror.
- Your child does not respond quickly when you call his or her name or needs to hear directions several times to respond. If a child does not have actual hearing impairment, being less responsive to auditory input can be a sign of poor registration of sound input.
- Your child has a particular difficulty finding objects in a drawer, toy box, or other storage space, even when the object is very visible. They may have visual perceptual deficits related to poor registration of visual information.
- Your child may perform writing, coloring, or other visual motor tasks in a way that appears careless and not notice their errors unless specifically pointed out. They may be having difficulty noticing the difference between good work and poor work.
Body Awareness (Proprioceptive Processing):
- Your child may have difficulty navigating through hallways without leaning against or rubbing their hands against the walls. This may be their way of compensating for decreased body awareness to help them understand where their body is in space.
- Your child may have difficulty maintaining upright posture, whether slouching in a chair, w-sitting on the floor, or leaning against a wall when standing.
- Your child may use excessive force when giving hugs or using objects (e.g. breaks crayons, throws balls too hard).
- Your child may prefer sleeping with very heavy blankets or prefer to keep their coat on indoors. This input gives them the weight he or she needs to better perceive where his or her body is.
Movement/Gravitational (Vestibular) Processing:
- Your child loves intense movement (i.e. spinning, rolling, or going upside down) and can do so for a significant period of time without getting dizzy or nauseous.
- Your child may appear clumsy when moving about and lose his or her balance unexpectedly.
Of course, as with any set of red flags, one or two red flags does not qualify for a sensory processing disorder. However, if quite a few of the sensory registration items above resonate with you, and if any of these items significantly interfere with your child’s daily functioning, it would be helpful to set up an evaluation with an occupational therapist.
Occupational therapists are specially trained to identify sensory processing disorder through parent interviewing and clinical observation of your child. If a disorder is identified, an occupational therapist can work with you to create a sensory diet, or prescribed set of sensory activities, to help your child get the input he or she needs to feel organized and calm to better learn and grow. They may also teach you strategies to help your child better attend to the input that is entering their body.