By Joanna Blanchard, MOTR/L
Pediatric occupational therapists often use words such as “sensory processing,” “proprioception,” “vestibular” or “registration.” What do these terms mean for children and how do these concepts translate to everyday experiences?
Sensory processing relates to our nervous system: organs including the skin, eyes, nose, mouth, tongue, ears, muscles and basically any other part of the body. When these areas of the body come into contact with, receive information and interpret the outside world describes sensory processing.
A sensory system in alignment provides the ability to:
- Take in sensory information
- Interpret and organize that information
- Respond meaningfully and effectively
This allows us to interact with our physical, social and cultural environment.
In layman terms, what does this look like?
Try this: take one of your forearms and squeeze it with the other hand. Firmly apply pressure, squeezing up and down the length of your arm, massaging for about 10 seconds.
Now, rest both arms at your sides or in your lap. Do you feel a difference between the two arms now? Congratulations, your sensory systems are working! (Or at least some of them are).
The touch alerted your tactile system and indicated that the touch to your arm wasn’t harmful. Your proprioceptors (little nerve receptors in your muscles and joints) felt pressure, movement, a change in activation and position and in turn “woke up” a little. Your vestibular system helped your body stay upright, balanced and remain still by mixing information from your eyes, core and neck and coordinating with your inner ear. That massaged arm is now awake and activated, yet strangely also relaxed and comfortable.
Each sub-system took in information and worked together with the others to interpret and adjust, drawing on previous experiences. All of the sensations were weaved together and integrated to make sense of what was happening, hence the term sensory integration.
This example provides a snapshot of how your nervous system works and how the brain puts together complex information. What’s presented to you is just how to simply feel things.
Now, imagine if your tactile system was hypersensitive and overactive to touch or input. Instead of feeling relaxed from the arm massage, the body might interpret the touch as uncomfortable as needles, unable to process if it’s a good touch or a bad touch, large or small, if one should pull away (flight) or strike out (fight). This is a system having a hard time with reception and interpretation of touch input.
The proprioceptive system, interpreting your muscles and joints, can also be underactive. A touch to the arm can produce a super slow, underwhelmed response: “Hey, do you feel something on that arm? Do we have to do anything about it? Because it takes a lot of effort to wake that arm up and move it, and plus I might fall off this chair. I just can’t do both the arm and my trunk at the same time. Let’s just shut it out.”
These are just two examples of how people register sensory information—the intensity an individual’s system registers and responds to sensory input. This varies from person to person and even day to day depending on fatigue, hunger, health and various other factors. A person can have different sensory preferences or levels of registration for different areas.
Some people love very hot showers (seeking intense tactile input), but hate loud sounds (avoiding intense auditory input). Some people love spicy foods, but can’t stand the feel of a fuzzy sweater. These are all normal variances among all people and even animals.
Sensory processing and integration comes from a primal need for survival that is ever-changing, depending on our situation. When a rabbit is munching clover, blissful in the sun and surrounded by other bunnies, his ears are down and his heart rate is relaxed. This helps filter out background noise (sensory input), such as the wind and birds.
However, once the bunny thinks he hears the cry or sees a shadow of a hawk fly overhead, he freezes. Suddenly he registers every single flicker of leaves and every twig snap: he is over-reactive, ready to run and hide. His heart rate increases, his muscles tense, his ears are perked up and he may even “eliminate” (poop or pee) to keep all of his body’s blood supply in his muscles instead of digestion. He will jump at the slightest sound and run if he can. This is how he survives.
If that bunny has an under-active system that doesn’t register (or misses) the cues, he will be easy prey. If the bunny has a constant overly-reactive system (on high alert, looking for hawks) all of the time, he will never be able to relax, eat or sleep. A stable, alert state and the ability to interpret sensory input correctly are needed for survival.
Typical sensory processing has a range and we all have individual preferences, some stronger than others. A sensory system struggling to interpret input correctly will struggle to feeling safe and comfortable, sort of like the bunny on high alert at all times.
When the sensory preferences or aversions become so strong that they interfere with a person’s ability to participate in everyday activities and quality of life suffers, it is classified as a disorder. Sensory Processing Disorder (SPD) happens when a person is unable to interpret or respond to sensory information appropriately, and it interferes with ability to function. While we can’t be comfortable at all times, participation in daily life should be attainable and if it isn’t, treatment options should be pursued.
Sensory processing disorders can be caused by motor, neurological or processing issues, under-or overexposure, trauma and sometimes it’s just “how we’re wired.”
Sensory processing disorder can manifest by affecting sleep, eating or elimination. Other signs include poor or delayed motor or language skills, fussiness, emotional instability, hyperactivity, distractibility or oversensitivity to stimuli.
Anxiety, attachment disorders, autism, Attention Deficit (Hyperactivity) Disorder are often co-existing conditions with SPD. Remember that bunny? If he’s an anxious bunny before he even goes outside, of course he is going to be on hyper-alert. Mental health treatment can help, which is why therapists often work together and combine treatment strategies.
Now, if the over-reactive bunny could assess how his friends are reacting, take deep breaths to calm down or stay close to a rabbit hole to feel safe, he would be using strategies to regulate his responses.
Sensory processing challenges can be supported and changed. How we respond or have strategies is how we self-regulate. Techniques can be learned to help lower our sensitivity or to get used to outside stimuli, adapt and respond appropriately.
In turn, therapy can help retrain our bodies and brains to help practice to increase the ability to tolerate stimuli. Occupational therapists use movement and sensory strategies to help practice this.
Our world is full of sensory input and we each bring our own perspective and reaction. How we take it in and respond is key to how we function, and also makes us each unique in what we find beautiful and exciting.