What is Sensory Processing Disorder?

By: Laura Van Zandt, OTR/L

As an occupational therapist, I have heard sensory referred to as many different things. Just a few examples include “sensory integration, sensory processing, sensory disorder, sensory dysfunction”. Not only is this confusing as an occupational therapist, but it has to be extremely confusing to parents too.

Sensory processing is a broad term that is used to refer to the way sensations are received and organized by the brain and how our bodies respond to this sensation and appropriately use it to interact within our environment. Our brains not only process information through the senses of touch, taste, smell, sight and sound but our brains also process information from our inner ear, muscles, joints, and ligaments to help us with movement and body position. All the sensory systems need to work together for effective sensory processing.

Overview of these sensory systems

• Visual sense: is the ability to interpret what is seen regarding contrasts of light and dark, color, and movement.
• Olfactory sense: is the ability to interpret smells
• Auditory sense: is the ability to interpret what is heard regarding volume, pitch, and rhythm.
• Gustatory sense: is the ability to interpret to receive taste sensations
• Tactile sense: is the ability to interpret touch sensations like pressure, vibration, movement, temperature and pain.
• Proprioceptive Sense: is the ability to interpret where your body parts are in relation to each other.
• Vestibular sense: is the ability to interpret information relating to movement and balance related

If there is inefficiency in processing sensory information, a child’s ability to function is compromised and there be difficulties in the child’s arousal, alertness, attention as well as play, self-care, fine motor and gross motor skills. This difficulty has increasingly become known as sensory processing disorder and was first recognized by Dr. A. Jean Ayres, occupational therapist, educational psychologist, and neuroscientists.

Sensory processing disorder can be a confusing term. No two children are alike. Symptoms of sensory processing disorder, like most disorders, occur within a broad spectrum of abilities. While most of us have occasional difficulties processing sensory information, for individuals with sensory processing disorder, these difficulties are persistent and can significantly disrupt everyday life.

Some children may experience difficulties processing sensory information in all or only a few areas of sensory processing. Likewise, it is also common for some children to not experience difficulties in any one sensory system but have difficulties combining the sensory systems to develop a meaningful response. A child’s response to a certain type of sensory input or activity may vary from one instance to the next and is impacted by the events preceding the activity, how the child feels (tired, fidgety, ill, healthy), and the context in which the activity occurs (quiet, noisy, busy, structured). When describing a child’s sensory processing, it is important to remember that anyone’s sensory processing patterns are merely a reflection of that person’s ways of responding to sensory experiences in the course of everyday life (at home and school). Knowing a person’s patterns creates a tool for gaining insights about what settings and activities are likely to be easier or more challenging and reveals possibilities for navigating successfully in everyday life.

Sensory processing disorders can be divided into three main areas: sensory modulation, sensory-based motor, and sensory discrimination.

Sensory modulation disorder refers to the ability to filter sensations and to attend to those that are relevant in a graded and adaptive manner whereas sensory discrimination disorder refers to difficulty interpreting subtle qualities of objects, places, people or other environments.

Sensory modulation disorder can further be broken down into children who are over-responsive, under-responsive, or sensory cravers/seekers. Children who are sensory over-responsive are often predisposed to respond too much, too soon, or for too long to sensory stimuli most people find quite tolerable. These children are often in ‘fight or flight’ to common daily sensations and may try to avoid or minimize sensations or act out to counterbalance feeling constantly bombarded.

For example, a child who is over-responsive to touch sensation may find physical contact, clothing, and other touch sensory input difficult. Children who are sensory under-responsive are often unaware of sensory stimuli, have a delay before responding, or responses are muted/less intense as compared to the average person. They may appear withdrawn, difficult to engage, or self-absorbed because they do not detect the sensory input to the environment. For example, a child who is under-responsive to touch sensation may not be aware of clothing twisted on their body or messes on their face. The child who is sensory craving is driven to obtain sensory stimulation but getting the stimulation results in disorganization. They tend to be constantly moving, crashing, bumping, and/or jumping. They may “need” to touch everything and not understand what is their space versus other space. Sensory cravers can be difficult to decipher between children with ADHD.

In children whose sensory processing of messages from their muscles and joints is impaired, posture and motor skills can be affected. Children with a sensory postural disorder may have a poor perception of position of body, poorly developed movement patterns that depend on core stability, and appear weak with poor endurance. When posture is impaired these children might seek additional support by leaning on walls or resting their head on their hands when working at the table. When motor skills are involved these children often have difficulty with the ability to make a plan to execute an action as well as execute the necessary actions supporting the performance.

Click here to link to our sensory processing intake form to see if your child might benefit from an occupational therapy evaluation to determine if there is a sensory basis for your child’s difficulties.

With effective treatment provided by an occupational therapist, your child can develop the ability to process sensory information in an adaptive manner and learn strategies to help him or her cope with everyday experiences. Our occupational therapists are trained to use a variety of different standardized tests and clinical observations as well as caregiver input to help put all the pieces together of the puzzle and make appropriate referrals. Then our therapists expertly look at the match between the child, the activities and expectations, and the context to determine when there is a mismatch that needs intervention attention.

For more information visit our sensory processing webpage and visit the links below.

• From our blog: What is Sensory Regulation? 
• From our blog: How sensitive is too sensitive?
• Star Institute for Sensory Processing: Systems Checklist