Protects us from stimuli that are interpreted by the brain as being harmful. Individuals with an over/under sensitive tactile system interpret touch differently. When tactile input is misinterpreted as being harmful, such as stimulation from certain types of clothing, food textures, or unexpected touch, it may elicit negative reactions such as pulling away, increased or agitated activity, or strong emotional responses. The heightened sensitivity to touch, resulting in routine misinterpretation or unusual reaction to touch is referred to as tactile defensiveness.
Allows us to have body scheme or an awareness of our body parts and the physical relationship of our bodies to objects and other people.
Helps us identify the size, shape, and texture of objects in our environment through our sense of touch. Provides us with the ability to distinguish the difference between a coin and a key in a pocket or to realize that a piece of food is still on your lip. Discriminating various aspects of touch provides the foundation for eating various textures of foods, using the hands for refined tasks, and knowing how to interact physically with other people.
The vestibular system provides us with a sense of security when moving. It is the foundation for the development of balance reactions and is important in motor development because of its influence on muscle tone, posture, the ability to use both sides of the body at the same time (bilateral motor coordination), balance, orientation in space, and eye movements. People who are frightened of moving or falling, often have difficulty with vestibular processing.
Proprioception is our muscle and joint sense, which helps us understand where our body is in space without looking. This allows for automatic movements without having to rely on our vision to monitor those movements such as being able to walk up a flight of stairs in the dark. It also provides information about how much force we need to use for tasks such as picking up a glass with different amounts of liquid, manipulating moving parts on a toy, and writing without thinking about the process of forming the letters. The ability to perform tasks without vision, such as wiping our face or pulling up our pants from behind, also requires proprioceptive processing. Oral motor skills require effective proprioceptive awareness, as a child cannot visually monitor their performance and must rely on input from muscles and joints in the mouth.
Proprioceptive input, obtained through moving, maintains and regulates body functions, including healthy neuromuscular and cardiovascular systems. People who exercise regularly may feel calmer and more alert. Children need increasing amounts of physical activity so that they can stay calm and alert throughout their day and proprioceptive activities can be a wonderful form of stimulation for calming and organizing the nervous system.
Our sense of sight and the ability for both eyes to work together
The auditory system provides us with the ability to hear as well as our ability to correctly understand what it is that we are hearing.
The olfactory/gustatory systems:
Our sense of taste and smell
Sensory integration is the foundation for us to be able to learn even the simplest things and to behave appropriately throughout our day. Sensations flow into our brain at every moment, and provide us with information that we can use to help us understand what is happening around us, to know what we need to do and to plan how to do those things. The brain detects and organizes these sensations to be able to form perceptions, adapt behavior and to support learning. Even very young children must be able to take in sensory information through all of the senses to perform skills automatically. They must be aware and comfortable with where their bodies are in relation to space; they must know where and how they are being touched and they need to know, without being taught, what sensory information to pay attention to and what to ignore. Many children however, have difficulty organizing information and performing the many complex tasks that are required for learning and functioning in our world. A. Jean Ayres, an occupational therapist and educational psychologist who developed Sensory Integration theory for use in therapy practice, once said, “When the flow of sensation is disorganized, life can be like a rush-hour traffic jam” (1979). These children, who have difficulty processing and using sensory information, may be diagnosed with sensory integration dysfunction, which may result in problems with development, behavior and learning.
Children with sensory integration dysfunction need all the help and understanding we can provide to them throughout their daily activities, to give them the support they need to even attempt routine tasks that most children perform easily.