Sensory processing

By Danni Verona OTR/L

On a sunny spring day in the park children can be seen playing, look closely and you’ll see a toddler happily playing atop a sand pile. Admiring his chubby little hands as he clumsily dumps the sand into his bucket; his mother watches and compliments his “nice scooping”. He smiles in response; concentration visible, movements rough but succinct, he joyfully gets the job done. Problem solving, fine and gross motor movements, shared attention, and playful social interaction are all accomplished because of the brain’s ability to receive and integrate sensory input into complicated plans of action.

It’s no small feat that a person whose only been on the earth for a couple of years can use tools and understand language all while remaining balanced and upright.  The human brain is made of areas that are considered old, and some that are newer in the evolution of human development. In the older part of the brain there are structures responsible for processing sensory information:  touch, taste, smell, sight, sound, balance and movement. The initial reception of all these pieces of sensory information is at the unconscious level. As sensory information is received it is processed and sent onward to be used by the different areas of the brain responsible for allowing us to move and think.

However, not all of the sensory information that our brain and body receives is used by our “thinking” brain; in fact the majority of the input we receive isn’t registered into our conscious awareness, it gets ignored or filtered out. If the brain actually had to be aware of all the input it receives through the eyes, ears, nose, mouth, skin and muscles we would be unable to function because of the bombardment of constant information. There are areas in our older brain that are responsible for allowing information to be registered and processed onto the higher thinking centers. These areas are like stations that direct the flow of traffic. Some of the traffic flows into conscious awareness, some is routed to more unconscious areas of the brain for basic body function, and then some is completely ignored by ceasing to continue sending that signal.

The work of childhood is to develop the brain’s “information stations” so they run smoothly and efficiently.  It’s a process of ongoing miracles that the brain creates the neuron connections that allow for ease of information flow that then allows for ease of living and function. From the very beginning of life it is through the child’s day to day experiences that the brain creates the foundational processing structures that serve for their lifetime. Thus the incredible importance of ensuring that the brain is exposed to daily opportunities for processing rich sensory experiences that create the pathways that will be the most efficient, and functional!

Newborn babies are incapable of getting themselves from place to place, so we carry them around on our bodies or snuggled safely in baby carriers. We tend to keep them limited in their exposure to harsh sensory inputs by protecting them with blankets and soft clothing as we transport them. Infants seem to be at their calmest, when we structure and limit the amount of sensory input their brains receive. Even with this limiting of sensory input, there is so much new information to the babies brain that they can only engage for short periods before shutting down and sleeping.  Then as their body grows and the brain makes more connections the babies begin to engage in as many experiences as the can. They crawl and toddle about getting into everything that stimulates their awareness.  Through the child’s ongoing exploration the brain begins the process of filtering and choosing the information that is important to have and that with which it need not bother.

As children engage in different activities the brain adjusts by sending the right types and amounts of sensory information that is required to actively participate in the experience.  Some activities require multiple pieces of sensory input to reach awareness. For example playing outside on a playground requires attention to a great amount of sensory input: The feel of the playground equipment, the muscles that must be used to climb and stay safe, the sights and sounds of the activity and the busy surroundings.  While other activities make more of a demand to disregard and choose what is needed to be successful for the present task at hand. Like when sitting and doing a puzzle, the “information stations” need to send up mainly visual information with a little bit of touch and muscle input for placing the pieces in the right spot, and keeping the head in the right position on the body. Appropriate filtering allows for the attention that gives the child their ability to focus, learn and remain safe.

Some children have difficulty filtering and processing the right amounts and right combinations of sensory information to be successful in their actions, this in turn can affects memory and learning. Their bodies receive the input through their senses but too much of one type of sensory input is processed and not enough of another.  Joey’s brain receives the touch information about the ball; he then puts the ball in his mouth. Joey’s brain receives a stream of tactile/touches information about the ball from the touch receptors in the mouth and hand, but he doesn’t register much more than that. Joey wants to explore the shape sorter bucket, but without some more information about the ball and the bucket he won’t be successful in placing the ball in the round hole. To be successful he will need to gather information about how the bucket looks, the sound it makes when the ball hits the side of the bucket, how much force is needed from his muscles…, but when he tries to put the ball into the bucket hole, he misses so he goes back to mouthing the ball and begins to cry.

Sometimes certain sensory systems (often the visual system) are so much more efficient than the other senses the child over-focuses and disregards the less efficient sensations of touch, sound or movement, consequently making those systems even less connected in the brain. Janey can see the blocks and she has the idea that she wants to stack them. She watches how her friend does it, but she isn’t getting the information from her body that tells her that when she put that last block on with too much force that’s when it fell over.  She can see how to do it, but struggles with the feedback information from her muscles, and touch receptors. Even when the teachers gives her verbal instructions to slow down her movements she doesn’t understand, Janey gets mad because all she knows is how it’s supposed to look all stacked up. But she doesn’t know how it feels in her body to successfully stack the blocks. So she knocks all the blocks off the table, including her friends, and now she just has the experience of feeling bad.

It is also true for all children that there are times when too much information about the surrounding environment is being allowed into awareness, so that the child looks around or moves every few seconds to explore something in the environment rather than the toy in front of them. Or on the other end of the spectrum is the child that is completely overwhelmed by too much information so their brain compensates by going into shut down mode, and “zoning out”, by not participating at all.

The brain must receive the right amount and right combination of sensory information in order to respond with appropriate action. Whenever the child creates an action there is feedback in the way of more sensory information. With each successful action and successful perception of feedback there is growth in the brain and there is learning. 

To place the ball into the round hole on top of the shape sorter bucket requires the brain to have information about the feel of the ball, the shape of the sphere(a combination of feel and look), the way the hole looks, and the way it sounds when it hits the side versus going through the hole. The brain must ignore the feel of the tag on the back of the tee-shirt, the sound of the truck outside as it passes and the sight of other toys in the area.  There must be successful sensory information integrated for successful plans of action.

When a child is not developmentally progressing, or their spontaneous learning seems too slow, or anger and frustration become the norm:  it’s time to adjust the environment, and create structure in the child’s experiences. In addition, attention must be paid to providing specific types of sensory input so that the parts of the brain responsible for integrating and filtering sensory information are working at their best; and that the child is receiving a wide variety of sensory input to develop all of the processors.

When using Sensory Integration strategies in a structured way as a means of providing a therapeutic opportunity there needs to be a focus on providing specific types of sensory input during activities, and at different intensities.

If the child has a particular weakness in a sensory processing area such as poor tactile (touch) integration, the activities chosen need to be offered in a predictable safe manner.

If general integration and regulation for processing are an issue, or if there are postural/ muscle tone issues then the child may be presented with opportunities to swing and jump so that the body can receive maximum input through the vestibular and proprioceptive processors.

If a child displays difficulty with focus and attention during activities, whether it is due to under-focus (poor filtering) or over-focus (excessive filtering), or modulation (poor transitioning, and overall difficulty with matching appropriate focus) the child will require specific physical activities that help prepare and maintain his nervous system for learning.

Activities designed to give more intensity of input to the total body can help the lower brain with proper attention and filtering. These can include big movement activities like swinging and bouncing, and total body activities like lotion play, or sitting in a tub of beans. Following and during these activities the child should be offered opportunities to play in a way that asks for physical action and then reaction. Some of the play will need to be structured to include opportunities for listening, following direction, and reciprocating interactions. But some activities can be very child driven with less structure and more spontaneous problem solving. The child’s tolerance and level of enjoyment will help guide which approach is best. However, it is important to remember that in order for new brain pathways to be made for real learning and memory, the child must be actively engaged. Passive reception of the sensory input may help prepare the child but in and of itself it does not provide opportunities for new learning.  As adults even when you are sitting and staring at a TV show, or a lecture, you won’t remember the information or be able to use it until you manipulate it in your mind, and somehow actively engage in thoughts about the information.  Our children need intense interaction in the way of play, and emotional responses before they will develop the ability manipulate and learn from experiences only occurring in their minds.

When a child is happily engaged in an activity in which there is shared interaction with another person and good attention to the activity- then at some level they are successfully integrating sensory information. If a child can play and respond to incoming sensory input, at whatever physical level they are able, and that play is interactive with ongoing opportunities to respond they are learning and successfully integrating. If the child can pass the ball back and forth, look up at the person to whom they are passing the ball, respond to even the simplest communications with action or words they are in a basic peak- processing mode. Having simple successes that then build the brain’s capacity for duplicating that experience is how we all learn. The complexity of the activity can then be increased to so that there is even greater opportunity for new learning.

In addition to considering the sensory qualities of our children’s worlds, Dr. Bruce Perry an expert in brain development and healing reminds us that the essential elements that every human being must experience in order to develop and be healthy are daily interactions in which there is : Safety, Comfort, Mutuality, and Pleasure. 

Our children who struggle with success, and/or whose behaviors challenge our enjoyment of them need us to stay mindful that if we want to improve their success and behaviors we must consciously create successful interactions with them. They need us to expand our awareness of their sensory world and consciously strive to create the experiences that allow for these essential human elements. They need us to create the environments and the opportunities to develop their brains ability to process and utilize sensory input.  And they need us to remember that when both parties feel safe, comfortable, mutually engaged, and are having fun- the opportunity for growth is greatest!

If the concepts presented in this article make sense, but you are still struggling with how to apply them to your child. And/or your child needs a person other than their loving caretakers to be a part of the program to assist your child’s development please contact your local Occupational Therapist.  If you’re in the Portland area, give me a call and we can chat bout how to serve your needs.