What is the vestibular system? An evidence based overview of childhood vestibular development
What is the vestibular system?
The vestibular system is one of our sensory systems that provides the sense of balance and information about head and body position. It is a key component in eye movements, keeping a stable gaze, postural reflexes and postural control and balance. The peripheral part of the vestibular system or the vestibular apparatus is located in the inner ear and is connected to the vestibular nerve which is part of the 8th cranial nerve or vestibulocochlear nerve. The vestibular nerve relays information from receptors in the inner ear about head and body motion and position to the brain which is the central part of the vestibular system. The cochlear part of the vestibulocochlear nerve relays hearing information from the ear to the brain. This is why hearing and balance are closely associated in children as they share the same space and nerve in the ear. The vestibular nerve is therefore primarily responsible for maintaining body balance and a stable gaze during head and body motion, while the cochlear nerve is responsible for hearing.
What are the functions of the vestibular system in children?
Maintaining a stable gaze on head and body movement
The development of muscle tone
The development of postural reflexes
The development of head control
The development of trunk or core control
The development of balance
Navigation and spatial awareness
Heart rhythm and regulation of blood pressure
Regulation of arousal levels
How does the vestibular system develop in children?
The vestibular apparatus develops in utero and is structurally fully developed at birth. However it takes until about 15 years of age for the vestibular system to fully develop. Therefore assessment and treatment of vestibular disorders in children are different from adults as the adult vestibular system is fully developed. For the vestibular system to properly develop it needs exposure to gravity. This is why tummy time and floor play without restriction is so important in the early months as it kick starts the vestibular system. Without this exposure to floor play and gravity (ie lifting head up off the floor on tummy and on back and through rolling), the vestibular system is not stimulated and there is a risk of developmental delay. In fact, there is now research that shows sufficient tummy time ie vestibular stimulation is strongly associated with improved motor developmental outcomes and lower body mass index. There are also albeit weaker associations of tummy time with improved speech and cognitive/learning outcomes. The critical period or most rapid change for vestibular development is in infancy up to preschool years. Therefore, early intervention for potential vestibular disorders is best to maximise child developmental outcomes.
What are common childhood vestibular complaints?
Unlike adults, children do not understand the term ‘dizzy’ and do not report being ‘dizzy’ which is what adults tend to report if their vestibular system is impaired. Vestibular complaints or hypofunction in children may present as follows:
1. Infants (0-2 years)
Lack of head control or a head lag
Poor tolerance of tummy time
A head tilt or side preference
Low muscle tone
Delayed rolling or resistance to rolling or just rolling over one side
Lack of ability to get in and out of sitting
Behaviour – irritable, poor tolerance of handling, cautious or fearful of movement
Standing – major difficulty in standing still and play in standing
Walking – toe walking or asymmetric foot/leg posture
Delayed onset of walking after 18 months of age
Global developmental delay
2. Children (>2 years)
Difficulty with motor skills such as walking up and down stairs
Difficulty with higher level skills including single leg balance, jumping, hopping, running
Avoidance of physical activity including playgrounds, riding a bicycle
Difficulty with walking or running and turning while doing do – may lose balance
Recurrent falls and below average balance for age
Constantly tripping, bumping into things/people
Difficulty walking or maintaining balance in the dark
Motor skills delay
Motion sickness, headaches
Reading difficulty due to difficulty with maintaining a stable gaze
Speech delay and learning difficulties
What are some conditions that can be associated with vestibular dysfunction?
Vestibular disorders are not rare in childhood but are poorly understood, overlooked and under studied. Research has reported overall prevalence between 0.7 and 15% of vestibular dysfunction (see above for vestibular complaints in children) in all children with the prevalence rising significantly in the following childhood conditions:
Acquired brain injury
Idiopathic Toe walking
Recurrent and chronic middle ear infections
Prolonged and chronic use of certain ototoxic antibiotics
Sensorineural hearing loss
Post cochlear implants
Post childhood cancer therapy
Developmental coordination disorder/dyspraxia
Labyrinthitis due to infection including mumps, measles, influenza, mononucleosis
Syndromes including Down Syndrome, Usher, CHARGE, Pendred, Cogan, Albinism
Benign Paroxysmal Positional Vertigo (BPPV)
Cranial trauma ie skull fracture
Torticollis or head tilt in babies
What should I do if I am concerned about my child’s balance and motor skills?
First and foremost it is always wise to visit your GP or a Paediatrician and share your concerns – your GP may refer onto a Paediatrician to check for any potential underlying medical causes for your child’s difficulties.
Your GP may also refer your child to a Chartered Paediatric Physiotherapist in the NHS or HSE who will assess your child and provide intervention, education and advice as needed.
You can also seek a specialist paediatric vestibular assessment with Deirdre O' Donoghue, Specialist Chartered Paediatric Physiotherapist (CORU and HCPC registered) at Move Kids Physio in Cookstown, Co. Tyrone who will conduct an in-depth neurodevelopmental, vestibular and motor skills play based assessment on your child and provide intervention and/or a home programme and education as needed. Go to Services | Move Kids Physio to find out more. Follow on social media; Resources | Move Kids Physio for ongoing information on vestibular assessment and rehabilitation in childhood.
Deirdre has received extensive training and certification in vestibular rehabilitation and has attended a number of paediatric vestibular training courses. Deirdre has also established a link with the Audiovestibular Department in Alder Hey Children’s Hospital in Liverpool in the event she feels that your child requires further testing of his/her vestibular system, she can refer directly to Alder Hey which is part of the NHS. To book an assessment you can email email@example.com or fill in the contact form on the website at Contact | Move Kids Physio.