By Romy Kruger
The world is a busy place, and it only seems to be getting busier. Life is fast paced, there always seems to be a lot going on and the to-do list is ever growing. So how do we manage to take in all that is going on around us, whilst still remaining focused on what’s important? The answer is, through effective sensory integration of incoming stimuli.
Sensory integration is the way in which you process sensory information from your body and your environment so that it leads to an appropriate behavioural response. It is therefore essential that sensory information is initially registered as being meaningful, modulated within the body and then suitably responded to. When sensory input is well modulated, adaptive responses can be made, allowing us to reach an optimal state of arousal for learning and functioning.
We all know about our five senses: sight, sound, taste, smell and touch. But there are two lesser-known but very important senses called the proprioceptive sense and the vestibular sense. Proprioception gives us an awareness of where our body is in space. It interprets input from the proprioceptive receptors in the muscles and joints in order to help us guide movement and strength behind actions. For example, you know how to grade your force accordingly when picking up an empty glass compared to a full one.
The vestibular sense provides us with information about our head in relation to gravity. It is our movement sense. The receptors for the vestibular sense are located within the ear. There are two different kinds of receptors, some which register linear, up and down, movement and others which register rotational movement. It is possible that a person can experience dysfunction within only the linear receptors and not the rotational receptors or vice versa.
The vestibular sense is intimately connected to the auditory (sound) sense as the receptors for both are located within the ear. The way in which vestibular activity influences auditory processing is not entirely known but it is known that these two sensory inputs travel side-by-side in a single nerve to the brain stem. They are neighbours and they talk to each other. It is therefore not surprising that people with sensorineural hearing loss, chronic ear infections or otitis media may experience vestibular dysfunction. It is often harder to pick up on this in children than in adults as adults are better able to express how they are feeling whereas with children, discomfort within the vestibular sense may present in behavioural outcomes such as withdrawing from movement, having meltdowns or seeking out excessive movement to increase registration within the system.
Children with vestibular dysfunction may present with the following signs:
- Distress when moving backward on the change table to have a nappy changed
- Distress when being picked up and having feet off the ground
- Difficulty tipping the head back in the bath for hair washing or lying on the back when learning to swim
- Intolerance of any change of movement of the head
- Maintaining the head in the upright position when bending down
- Difficulty with balance
- Difficulty maintaining standing balance with closed eyes
- Fear climbing up and down stairs
- Motion sickness
Jean Ayres, the founder of Sensory Integration therapy, believes that one of the most basic of all human relationships is our relationship to the gravitational field of the earth. Sensory integration of the vestibular system gives us the trust that we are securely connected to the earth and will always have a safe place to stand. Gravitational security is the basis upon which we build our interpersonal relationships. You can therefore imagine that if a child or adult has a hearing impairment the world is already a scary place as one of the primary senses has been eliminated. If a vestibular dysfunction is placed on top of that, incoming stimuli from the environment is not being accurately and effectively integrated thus making it hard to build relationships, learn new tasks, and plan actions and behaviours.
If you think you or your child is experiencing sensory processing difficulties, an Occupational Therapist trained in Sensory Integration Therapy can help you.