SENSORY PROCESSING is a complex neurological process that influences the functional skills in most individuals. People with Sensory Processing Difficulties misinterpret everyday sensory information, such as touch, sound and movement. They may feel overwhelmed by sensory information, may seek out sensory experiences or may avoid certain experiences. Sensory Processing Disorder is not a recognised disorder and is not listed on the DSM-5.
People with SPD experience their world as either Hypersensitive (over reactive, sensory avoidance) or Hyposensitive (under reactive, sensory seeker). They may also present with motor skill problems. They may react with strong emotional behaviours and experience what may be described as ‘melt downs’.
The brain and nervous system receive input from body parts as well as from the outside world. The central nervous system is also a means of transmitting messages throughout the body and functions somewhat like a computer system. The messages that are transmitted, however, affect functions such as muscle movement, coordination, learning, memory, emotion, behaviour and thought. As with a computer, a breakdown or malfunction in one part of the system often affects other functions of the system.
Sensations from hearing, vision, taste, smell, touch, pressure, and movement provide the input to the brain which is organized for movement, cognition and learning. The richness of the sensory environment and the interactive experience of the individual with the environment contibute to optimal development of function.
When there is a Sensory Processing dysfunction, it is hypothesized that the brain does not process or organise the flow of sensory impulses in a way that gives the child precise information about themselves and their world.
As a result, learning can be difficult and children may feel uncomfortable, or have difficulty coping with the stress of daily sensory and organizational demands. This often results in additional or behavioural difficulties.
Sensory Integration (S.I.) is the term used to describe the way in which the brain sorts out and organizes for our use the many sensations which we receive.
Dr Jean Ayres defined sensory integration as, ‘the neurological process that organizes sensations from one’s own body and from the environment and makes it possible to use the body effectively within the environment” (Ayres, p11, 1989).
Sensory Integration is the body’s ability to:
1 Receive or take in sensory stimuli
2 Interpret the stimuli
3 Process the stimuli into a response; and
4 Adaptively respond to the stimuli
The sensory system takes information from the surrounding environment through touch, smell, sound, vision, taste, movement and gravity. It processes or interprets these sensations together to make sense of the environment. The process of sensory integration lays the foundation for efficient operation of the nervous system and other parts of the body that respond to the signals sent by the nervous system. The child then responds to these sensory inputs and makes appropriate responses to perform skills required.
These difficulties put children with SPD at high risk for many emotional, social, and educational problems, including the inability to make friends or be a part of a group, poor self-concept, academic failure, and being labelled clumsy, uncooperative, belligerent, disruptive, or “out of control.” Anxiety, depression, aggression, or other behaviour problems can follow. Parents may be blamed for their children’s behaviour by people who are unaware of the child’s “hidden handicap.”
Effective treatment for SPD is available, but far too many children with sensory symptoms are misdiagnosed and not properly treated. Untreated SPD that persists into adulthood can affect an individual’s ability to succeed in marriage, work, and social environments.