Sensory Processing Disorder (SPD)

Sensory processing disorder (SPD), formerly called sensory integration dysfunction (SID), is the brain’s inability to intelligibly manage multisensory integration—important for developing motor skills, social-emotional relationships, and cognitive skills. SPD makes it challenging to meet the body’s minute-by-minute demands internally/externally, leading to difficulties in school, play, sports, work, relating to others (especially in groups), and dealing with stressors. Sensory challenges can be over-/under-reactive to sensory experiences. Also see Sensory-Based Motor Disorder (SBMD), with two subtypes (dyspraxia and postural disorder) and Sensory Discrimination Disorder (SDD). SPD most negatively affects three sensory systems:

• Somatosensory (tactile) system recognizes touch sensations (pressure, temperature, pain) through the skin, so we can touch and understand objects.
• Proprioceptive system helps orient the body and understand its spatial relationship to the environment through proprioceptors in the muscles and joints.
• Vestibular system, through a complex organ in the middle ear, determines movement, equilibrium, balance, and eye-hand coordination.