Sensory Processing Disorder (SPD)

Sensory Processing Disorder (SPD) is a condition that affects how your brain processes sensory stimuli.  Children with SPD will either overreact or under-react to sensory stimuli.  There are 3 major patterns of SPD including Sensory Modulation Disorder (SMD), Sensory-Based Motor Disorder (SBMD), and Sensory Discrimination Disorder (SDD).  


Sensory Modulation Disorder is when a child has difficulty regulating responses to sensory stimuli.  It consists of three subtypes including sensory over-responsiveness, sensory under-responsiveness, and sensory craving. Sensory over-responsiveness is having a response to sensory stimuli that is much greater or lasts for much longer than it would for most people. Sensory under-responsiveness is a below average response to sensory stimuli where the person may seem unaware of stimuli or experience a delay before responding. Sensory craving is when a child is driven to obtain sensory stimulation.  These children present as being on the move constantly and have a preference for crashing, bashing, jumping, spinning, swinging, and/or rolling. Not obtaining the stimulation typically results in disorganization.


Sensory Based Motor Disorder (SBMD) refers to difficulty with balance, motor coordination, and performance of skilled tasks. Two subtypes of SBMD are postural disorder, which is an impaired perception of one’s body position that results in poorly developed movement patterns, and dyspraxia, which is difficulty planning and/or executing skilled movements. Children with SBMD may have difficulty learning new motor skills, often trip or bump into things, appear clumsy or awkward, and may be accident prone. 


Sensory Discrimination Disorder (SDD) refers to difficulty organizing and interpreting sensory stimuli received from the body’s senses.  Auditory DD is difficulty interpreting stimuli that is heard, Visual DD is difficulty interpreting stimuli that is seen, tactile DD is difficulty interpreting stimuli that is felt on the skin, gustatory DD is difficulty interpreting stimuli that is tasted, and olfactory DD is difficulty interpreting stimuli that is smelled. In addition to these five senses, individuals rely on the proprioceptive system, vestibular system, and interoceptive system. Proprioception involves how the brain understands where the body is in space, therefore, proprioceptive DD is difficulty interpreting stimuli experienced through the muscles and joints. The vestibular system provides a sense of balance and allows the body to adjust accordingly with movement, therefore, vestibular DD is difficulty interpreting stimuli that is experienced by movement of the body through space or against gravity. Vestibular dysfunction may present as dizziness, frequent loss of balance, or clumsiness.  Interception, which is sensations related to internal organs, may present as complaints of frequent stomach aches or bathroom accidents because the child may not feel the need to use the toilet.


Occupational therapy can help children develop coping skills for dealing with sensory stimuli so that they do not feel overwhelmed or become withdrawn when presented in a sensory rich environment. Tactile and vestibular experiences are an essential component of sensory integration and are often used as organizing factors in treatment. Sensory integration therapy offers a variety of strategies to address the ranges of the disorder and helps restore a healthy lifestyle for the child by engaging in meaningful occupations.

Written By Tyler Boening, OTS