Also known as sensory integration dysfunction, sensory Processing disorder is a complex neurological condition in which responds poorly to the information that comes in or has trouble receiving information.
There are three important categories of sensory processing disorders: sensory based motor disorders (SBMD), sensory modulation disorder (SMD) and sensory discrimination disorder (SDD).
The SMD consists of under-responding and over-responding to sensory stimuli. In SBMD, as a result of incorrect processing of sensory information the motor output is disorganized resulting in developmental coordination disorder and/or postural disorder.
The symptoms vary depending on the disorder’s type and subtype. Therefore, people suffering from sensory over-responsivity might: avoid crowds and noisy places, get extreme car sick, feel discomforted by normal lights, sounds, smells, tastes or even sensations like their own heartbeat. Also they can be very picky eaters, have sleep disorders, feel constant under stress and dislike textures in foods, fabrics or grooming products. They can go as far as refusing to hug or kiss because they have a very negative reaction to the contact with the skin.
People suffering from under-responsivity might have difficulties waking up, be unaware of pain or the presence of other people, might be unreactive and slow and sometimes might appear deaf. People suffering from sensory craving might seek or make disturbing, loud noises, seek extreme sensation, crash, jump and climb constantly or fidget excessively.
People suffering from SMBD might have poor posture, appear slow and uncoordinated and feel clumsy and slow. People suffering from sensory discrimination problems might have poor handwriting, use inappropriate force to handle objects, drop things constantly and have difficulty eating and dressing.
Damage in any part of the brain can be the cause of the disorder. The current research focuses on finding the neurological and genetic causes of the SPD. People diagnosed with SPD should seek the specialist help of a neurologist for a better understanding of their situation and the things they have to do to improve the quality of their life.
Some of the possible causes under research are increased D2 receptor in the striatum, genetic influences in people with auditory and tactile over responsivity, the sensory gating and the abnormal microstructure of white matter in children suffering from the disorder.
Sensory processing disorder is not recognized yet in the DSM – 5 and the ICD – 10. Diagnosis is based on expert observational scales, standardized questionnaires, standardized tests and free play observation at an occupational therapy gym. Diagnosis is made by different professional depending on the country. The professional that might be responsible for a diagnosis might include psychologists, speech and language therapists, occupational therapists and physiotherapists.
Standardized tests include TSI (DeGangi-Berk Test of Sensory Integration), SIPT (Sensory Integration and Praxis Test), TSFI (Test of Sensory Functions in Infants). The questionaries used most often include SPM (Sensory Processing Measure), SPSC (Sensory Profile School Companion), SP (Sensory Profile), Infant/Toddler Sensory Profile, APM-P (Sensory Processing Measure Preeschool). There are also o few tests that might be used as well such as COMPS (Clinical Observations of Motor and Postural Skills), BOT-2 (Bruininks–Oseretsky Test of Motor Proficiency, Second Edition), DTVP-2 (Developmental Test of Visual Perception: Second Edition), Miller Function & Participation Scales, BRIEF (Behavior Rating Inventory of Executive Function).
The treatment developed to treat the SPD might include sensory integration therapy, sensory processing therapy, physical exercise, prism lenses and auditory integration training.