Sensory experiences include touch, sight, sound, smell, taste, movement, body awareness and pull of gravity. Sometimes one or more of these senses are either overactive to stimulation or underactive to stimulation.
Although sensory receptors are located within the peripheral nervous system (includes everything except for the brain and spinal cord), it is researched that the sensory problems occur from neurological dysfunction in the central nervous system (brain). The dysfunction may produce varying degrees of problems in development, information processing and behaviours.
Sensory integration focuses primarily on three basic senses, tactile, vestibular, and proprioceptive. A dysfunctional tactile system could lead to misperception of touch and/or pain (hypersensitive/hyposensitive). Tactile defensiveness occurs when the individual is extremely sensitive to light touch. These types of stimulations in the brain create difficulty for the individual to organize.
The vestibular system refers to structures found within the inner ear (semi-circular canals) that detect movement and head positions changes. Dysfunction may cause hypersensitivity to vestibular stimulation and cause fearful reactions to ordinary movement activities (e.g. swings, slides) and may also be apprehensive walking or crawling on uneven terrain. On the other extreme of dysfunction, some individuals demonstrate a hyporeactive vestibular system that they are trying to continuously stimulate.
The proprioceptive system refers to components of skin, muscle, joints, tendons that provides an individual with a subconscious awareness of postural positioning, it also allows for fine motor movements such as using a spoon or pencil. Dysfunction can result in clumsiness, lack of body awareness or odd posturing, difficulty crawling and manipulating small objects and a resistance to new motor movement activities.
Overall a dysfunction within sensory integration can cause hyper or hypo reactions throughout all areas. Manifestations of these are individualised and can cause fine and great motor movement/coordination delays or concerns. For further information speak with us at The Timmermans method or your child’s pediatrician or Occupational Therapist as there are other methods for assisting with sensory input.