Sensory Stimulation In Autistic Children - Processing, Behavior

Children with autism may have a dysfunctional sensory system which can lead to one or more sense to be either over active or under active to stimulation. Such sensory stimulation problems may be the cause for behaviours such as rocking, spinning and hand-flapping. Though these receptors for the senses are located in the peripheral nervous system, it is believed that the trouble emerges from neurological dysfunction in the central nervous system- the brain.

Sensory Integration in Child with Autism

Sensory integration focuses on three basic senses, that is, tactile, vestibular and proprioceptive. They are interconnected and start forming before birth and develop until the individual is matured and starts interacting with his/her own surroundings. These Sensory stimulation senses are also connected with other systems in the brain and are critical to our basic survival. The inter-relationship between these three senses allows us to experience, interpret and respond to different stimuli in our surroundings.

Let us look at these three senses below, in depth.

1. Tactile System:

   Tactile system consists of the nerves under the skin’s surface that sends information to the brain such as pain, touch, light, pressure and temperature. These senses are known to play a vital role in perceiving the environment and enhance our protective reactions for survival.

   Dysfunction in tactile system can be noticed when your child starts withdrawing on being touched, refuses to eat certain kinds of textured food, refuses to wear certain kind of clothing, complaining about having washing his/her face or hair and even avoid getting his/her hands dirty in mud, clay or even glue.

   A dysfunctional tactile system may lead to a misperception of touch and or pain (hypersensitive or hyposensitive) and may lead to self-imposed isolation, general irritability, distractibility and hyperactivity. Tactile defensiveness is a condition in which a child can get extremely sensitive to light touch due to the system working in an improper way.

   In this, abnormal neural signs are sent to the cortex in the brain which can interfere with other processes in the brain. This can cause an overly stimulated brain which can lead to excessive brain activity, which can neither be turned off nor organized. This can make it tough for a child to organize his/her behaviour and concentrate, leading to negative emotional response to touch sensations.

2. Vestibular System:

   The vestibular system refers to structures within the inner ear that can detect movement and changes in the position of the head. It is the vestibular system which tells an individual whether his/her head is upright or tilted. Dysfunction in this system can manifest itself in two ways. A child might be hypersensitive to vestibular system and have fearful reactions to ordinary movements such as swings, slides and even ramps.

   They also have trouble in climbing or descending the staircase and always seem to be fearful and clumsy in big spaces. In extreme cases, a child may seek intense sensory experiences such as excessive body whirling, spinning or jumping.

3. Proprioceptive System:

   The proprioceptive system refers to components of muscles, joints, and tendons that provide a person with a subconscious awareness of body position. When this system is working efficiently, an individual’s body position is adjusted in various situations and also receive the essential signals to allow one to sit properly anywhere. This system also allows a child to manipulate objects using fine motor movements such as writing with a pen or a pencil, using a spoon to drink and even buttoning a shirt.

   Common signs of this system’s dysfunction are clumsiness, tendency to fall on and off, odd body posturing, lack of awareness of body posture, minimal crawling when young and troubles in manipulating objects such as unbuttoning a shirt or spilling when eating or drinking.

    

A child may be over or under responsive to sensory input and his/her activity level might be either very high or very low. A child might be in constant motion or can get tired easily. At times a child can even fluctuate between these extremes. Dysfunction in these systems may result in language and speech delays, under achievement in academics, become easily distractible, impulsive and irritated. At times the child will find it hard to adjust to new surroundings and might get easily aggressive, frustrated, resulting in withdrawal.

Evaluation and treatment of these basic senses are performed by an occupation therapist or a physical therapist where the aims are to provide the child with sensory information which helps to organize the central nervous system, assisting the child in modulating sensory information and processing an organized response to sensory stimuli.