Sensory integration refers to the interaction of different sensory systems or sensory qualities.
What is sensory integration?
Sensory integration is a process that occurs everywhere in the brain. It includes, for example, vision, hearing, taste, smell, movement, and body perception. Sensory integration (SI) is the term used to describe both the ordering of sensory impressions and a therapeutic concept developed by psychologist and occupational therapist Dr. A. Jean Ayres in the 1960s and 1970s. She noticed that there are children who suffer from a disturbance pattern, but where no damage can be proven. Sensory integration is a process that occurs everywhere in the brain. It includes, for example, sight, hearing, taste, smell, movement, and body perception. How the body processes these stimuli varies from individual to individual and depends on the quality of the sensory systems. Sensory integration is thus the basis for learning, speaking and acting. The information that one takes in via the sensory systems is processed in the brain and then translated into appropriate actions. Sensory integration begins during pregnancy and develops very rapidly, especially in early childhood. This is extremely important because in the early years, sensory systems are interconnected and the foundation for language, agency, social behavior, coordinated movement, and imagination is formed.
Function and task
Sensory information from the near senses plays a very essential role, especially in the first years of life. The near senses provide the brain with information about the body and what position it occupies in the environment. A distinction is made between:
- Touch or tactile sense (tactile sense).
- Sense of balance (vestibular sense).
- Sense of movement and strength (proprioceptive sense).
If a child in the first years of life is able to process the different sensorimotor experiences very well, it can develop a differentiated image regarding the limits or possibilities of the body. This image is also called body schema. If sensory information can be ordered and put together in the brain, this process is called “sensory integration”. A good sensory integration is necessary to be able to orientate in the environment. For this purpose, all information from the environment or from the body must be processed. This information is then received by the receptors located in the sensory organs. These include:
- The tactile corpuscles of the skin, which are important for touch.
- The arcuates in the middle ear for balance and gravity stimuli.
- Receptors in the joints and muscle spindles for informaitons regarding the range of motion.
Subsequently, the nerve pathways transmit the information to different brain centers, most of which are processed unconsciously and automatically. Important processes already take place in the brain stem, the lowest brain section. Here, for example, equilibrium stimuli are processed so that adaptation to changes in position is possible automatically. Unconscious processing is important because we need our attention for higher performance.
Diseases and disorders
If the interaction of sensory modalities is disturbed, sensory integration disorders occur. Sensory integration disorder refers to a mild neurological dysfunction in which sensory information cannot be adequately processed. As a result, the person cannot adapt his behavior to the requirements and reacts less purposefully and sensibly. The manifestations are very different. For example, the basic tension of the muscles may be hypotonic, i.e. too low, so that those affected have to make a conscious effort to maintain postural stability. However, the necessary attention is then no longer available for other activities. Children who suffer from this appear very limp and are restless. Other children, on the other hand, cannot plan their movements purposefully and are therefore extremely clumsy. Another disorder manifests itself in vestibular hypersensitivity, also known as modulation disorder. In this case, the child is unable to inhibit or filter stimuli.If the child is tactilely defensive, he or she avoids unexpected touches of people or materials that have a diffuse stimulus quality. Children react defensively and aggressively to such touches. Therefore, situations such as subway rides or waiting lines are avoided, which can also cause social anxiety. Vestibular defensiveness is an extreme form of fear of heights triggered by activities such as riding a bike or swinging. Children suffering from sensory integration disorder often show the following symptoms:
In infancy:
- Defensiveness or irritated behavior to touch.
- Defense or irritated behavior to changes in the situation
- Restlessness and crying episodes and very low activity levels
- Swallowing and sucking problems
- Disturbances of the sleep-wake rhythm
In infancy or school age:
- Sound sensitivity
- Lack of body or self-confidence
- “clumsy” children
- Delayed motor development
- Delayed linguistic development
- Stress and behavioral problems
- Hypo- or hyperactivity
- Learning or partial performance disorders
Sensory integration disorders are the result of a wide variety of processes. For example, they can occur due to a lack of developmental stimuli. Moving and active play are therefore eg extremely important for development. Children otherwise have few opportunities for sensory experiences and experience little physical contact. But overstimulation by stimuli can also cause a disorder. As a result, processing breaks down and the stimuli are only incompletely transmitted. Adults can also suffer from a sensory integration disorder, usually they then also had problems as children in the area of perception or it was not sufficiently challenged and encouraged.
