MOVEMENT, MUSCLE TONE, MIDLINES & BALANCE

Mirror neurons and baby development
June 7, 2019
Jaws attends playgroup
September 17, 2019

By Dr Melodie de Jager

Can you remember when you learned to walk, ride a bike or ice skate? The hardest part was to start and to stop? Once in motion, it was easier to maintain balance and to keep going. You may wonder why it would be easier to maintain balance and keep going while in motion.

Movement helped you to maintain your balance.

Increasingly, we notice learners moving about in class, ‘needing’ to: throw a paper away, sharpen a pencil, go to the toilet, fidget, rock, bounce, etc. In an attempt to satisfy the learners’ need to move,  many educationists have suggested the use of stress balls to keep the hands moving, sitting on large gym balls to allow for contained movement, doing goal specific movements in class, and chewing gum.  All of these strategies are an attempt to stimulate the vestibular system and in so doing, enable the children to sit still and concentrate. But that sounds like a contradiction – move to sit still?

Balance is not something you HAVE. It is something you DO. Schrager

  1. WHAT IS BALANCE?

Balance is the ability to ‘hold’ a posture while doing something else – sitting up while reading, writing or listening in class, bending down while fastening a shoe, walking while talking, carrying a cup of tea without spilling, catching a ball while running, skating while waving, driving while listening to the radio, etc. Balance is the ability to keep the body upright and still, while simultaneously using lots of muscles to make minute movements, resulting in the body performing a seemingly effortless task.

There are two kinds of balance, static balance and dynamic balance.

Static balance

Static balance is the ability to hold a posture in the same location, but without support, e.g. sitting while playing a clapping game, standing on one leg, sitting upright while listening or reading. Static balance is also called a state of static equilibrium.

Static balance is monitored by the maculae receptors within the membrane of the vestibular system (Marieb, 2000), which are responsible for registering the position of the head to the pull of gravity when the body is not moving (Marieb, 2000). Each macula is a patch of receptor cells with their hairs embedded in the otolithic membrane. This membrane consists of a jelly-like material and contains small particles made of calcium salts, known as otoliths. During head movement, the otoliths roll in response to the changes in the pull of gravity. The rolling otoliths slide over the hair cells, bending the hairs and pulling on the otolithic membrane. The activated hair cells send an impulse along the vestibular nerve (a division of cranial nerve VIII) to the cerebellum of the brain, informing it of the position of the head in space (Marieb, 2000; Hogan, 2004).

Fig 1: Static Balance: structures and function of maculae (Marieb, 2000). 

This is practically illustrated by a spirit level with three tubes angled to indicate equilibrium – the midpoint, between moving backward and forward, up and down, and left and right. A still and straight posture would imply that the three bubbles within the three angled tubes of the spirit level would simultaneously be at midpoint.

The absence of static balance is when a prop (like an arm or a wall) is needed to stay upright.

Concentration would then be more focused on maintaining balance rather than on writing or reading.

Dynamic balance

Dynamic balance is the ability to hold a posture, while moving in a co-ordinated way, using appropriate muscles to do a task with minimal effort and maximum effect. Dynamic balance is also called a state of dynamic equilibrium and is monitored by receptors in the semi-circular canals, which respond to rotational movements of the head. This can be illustrated by a snow globe, where the ‘snow’ gets unsettled every time the head moves. Since these canals are orientated in the three planes of space: forward/backward, up/down, left/right, any movement of the head will be detected by the direction in which the ‘snow’ is moving.

 Fig 3: Dynamic balance: structure and function of the crista ampullaris (Marieb, 2000)

Dynamic balance is monitored by the maculae receptors within the membrane of the vestibular system, which are responsible for registering the position of the head to the pull of gravity when the body is moving in a linear manner (Marieb, 2000).

The opposite of dynamic balance is when a child trips easily, seems clumsy and uses additional movements to prevent her from falling. The absence of dynamic balance often goes hand in hand with movement of the jaw, mouth, tongue and hands. 

  1. THREE PLANES OF SPACE

Gross motor movement is needed to activate the proprioceptive and vestibular systems before balance is possible. Gross motor movement is naturally prompted by the primitive reflex system to get the baby moving. In time, a baby will move on three planes: backwards and forward (when he engages in suckling, or moves towards and away from touch), up and down (when he starts sitting up and later pulling up to walk), left and right (when he starts cruising around furniture or turning to see). These early movements are made in preparation for static and dynamic balance later and develop with the help of the three semi-circular canals within the inner ear.

Movement on any of these three planes disturbs balance and activates the ‘spirit level’ in the semi-circular canals.  This in turn determines the direction of the movement that is taking place, and it instructs the inside senses on how to respond to counteract the movement and maintain balance. Moving ‘snow’ indicates rotation and settled ‘snow’ indicates ease at restoring balance. The moment balance is regained, the ‘bubbles’ in the three semi-circular spirit levels are all in the centre, the ‘snow’ is settled, and you know where you are in space.

Each semi-circular canal correlates with a plane of space:

  • Lateral plane:  forward and backward movement, and stopping along a horizontal axis, like sitting, bending forward, rocking and swinging, forward and backward rolls, or on a scooter board up and down a ramp.
  • Superior plane:  horizontal movement, and stopping around a vertical axis, like turning and spinning on a carousel, or playing ring-a-rosy.
  • Posterior plane:  tilting movements, like when in a plane or a boat, and when balancing on a wobbly board or a big gym ball, walking over a hang bridge, or playing on jumping castles and trampolines.

Movement helps to maintain balance over a small base of support. 

  1. MOVEMENT AND THE PULL OF GRAVITY

According to Goddard (2002) the one relationship everybody on earth shares, is the relationship with gravity. Gravity refers to Newton’s law that if it goes up, it will come down. It is the down-pull of gravity that provides you with a sense of stability – a reference point or a sense of centeredness. Ayres (1980) calls this sense of centeredness, ‘gravitational security’.

The down-pull of gravity on the body creates a secure and stable base from where you can:

  • orientate yourself in space (Where are you: in front, behind, next to? Where are objects: on top, under, in between? Which way does a b face: to the left, or to the right? Does a p go up or down?)
  • experience time (before, after, during, 7 o’clock, lunchtime, evening, Monday, winter, birthday)
  • integrate information from various senses (sensory integration, visual and auditory processing)
  • develop muscle tone (balance between flexion and extension of muscles)
  • praxis – the ability to choose responses, arrange them in order and to execute the response
  • judge direction, depth, height, weight, speed, distance and velocity (distance and speed between an on-coming car and your ability to cross the road safely, ball games, strength needed to lift a chair, height of a step, the strength needed to kick a goal)
  • plan (what is in place, what is needed, what needs to happen)
  • engage in activities and with people
  • establish a sense of self.

The pull of gravity interacts with the body (vestibular system) to work like a Global Positioning System (GPS), which requires specific input:

  • Where are you?
  • Where do you want to go?

Once these two bits of information have been perceived, the GPS calculates the route or plan of action. If the GPS is faulty, you would get lost, feel distressed and be in need of help.

The same applies if a child’s vestibular system’s relationship with the pull of gravity is faulty – a child may feel lost, distressed and be in need of help.

Typical symptoms of a faulty human GPS (proprioceptive & vestibular systems):

  • tactile defensiveness
  • stiff posture
  • can’t hop or balance on one leg
  • can’t walk backwards
  • battle to skip and gallop
  • can’t skip with rope
  • clumsy
  • accident prone
  • poor motor planning
  • gets motion sick
  • poor static and dynamic balance
  • vertigo (dizziness)
  • find climbing down stairs difficult
  • avoid rope bridges
  • fear of heights
  • poor spatial orientation
  • can’t tell left from right without a marker
  • reversals
  • disorientation
  • low muscle tone
  • have problems crossing the midlines
  • avoid writing and reading
  • dyspraxia
  • dysphasia
  • dyslexia
  • dysgraphia
  • dyscalculia
  • Asperger Syndrome
  • avoid sport and dance
  • poor sensory processing
  • uncontrolled eye movements
  • poor perception
  • hyper alert/active or hypo alert/active
  • attention deficit
  • delayed language development
  • anxiety disorders
  • phobias
  • panic disorders
  • mood disorders
  • self-esteem disorders
  • repeated rocking, shaking or banging of head
  • swing for long periods of time
  • thrill seeker
  • dominant hand not established
  • rather watch TV or play computer games than play outside.

(Adapted from Levinson, 1984; Blythe & McGlown, 1979; Goddard, 2004) .

Barriers to learning such as those listed above can be addressed by improving the proprioceptive and vestibular function and the relationship with gravity, in order to develop a secure and stable base from which to learn and relate with greater ease.

  1. HOW DOES A SECURE AND STABLE BASE DEVELOP

A secure and stable base develops as the result of static and dynamic balance. If balance is lacking, you may compensate for it, but this means concentration is divided – the greatest portion of concentration is directed towards the physical component of an activity and the remaining portion of concentration is directed towards the skills associated with an activity, with an obvious negative impact on learning. For example, when learning to ride a bike, a child may start off by using fairy wheels to broaden his base – to provide gravity with a bigger surface to attach to and to keep him stable. As balance improves, the fairy wheels may be removed, while balance is maintained on a narrow base (2 wheels).

Broaden base with legs in w-position for more stability.

Stable and narrow base of support enhance concentration.

This can also be seen in young children when they need to sit with their legs in a ‘w-position’ to broaden their base so that they do not fall over; or when a child needs to support his head with his arm or hand while reading or writing; or when a child continuously moves forwards/backwards, side to side, or bounces up and down. All of these are desperate attempts to get the ‘bubbles’ in the centre of the three tubes of a spirit level, to maintain balance on the three different planes.

Movement broadens the base, and without moving, these children cannot balance; and without balance, they cannot sit up or sit still and concentrate. To be able to be still and concentrate, they wisely broaden their base to get some support from gravity so that they can stay upright.

For these children to be able to maintain their balance over a small base of support, it is important that the base remains stable – a stable base is created by a stable head and a strong core.

  1. HOW DOES A STABLE HEAD & STRONG CORE DEVELOP

Balance is only possible when a stable head and strong core muscles have developed. For this to happen, the outside and inside senses need to combine their efforts. When this process is done effectively, it is called sensory integration.

Outside senses

The outside senses are the senses that respond to sensations and stimulation from the environment through the sense of touch, smell, taste, hearing and sight. These five outside senses provide the inside senses with information about any changes in the outside in the environment.  They also rely on the inside senses to make the necessary adjustments, to enable a child to adjust to the environment.

Inside senses

The inside senses are senses that respond to sensations and stimulation from inside the body; and include the proprioceptive system, vestibular system and kinesis. 

The inside senses have the ability to find gravitational security, to determine who or what is moving, and to assess if you need to move to make any adjustments. For example, when the inside senses detect a car moving right next to you while you are stationary at a red traffic light, the inside senses determine whether it is you, or the other car, that is moving. The same applies to a child who falls off his chair when someone else is walking past his desk. His inside senses are not working efficiently and therefore he cannot tell who is moving. 

Proprioceptive system

“Propria” is derived from Latin meaning ‘one’s own’. The proprioceptive system is ‘one’s own’ conscious and unconscious awareness of the body position and its movement in space.

The proprioceptive system is also called ‘muscle sense’, and tells the brain:

  • when and how the muscles of the body are contracting or stretching;
  • when and how the joints are flexing, extending, or being pulled or pushed;
  • where one’s body parts are in space and what they are doing;
  • the rate and timing of movements;
  • how much force muscles are exerting; and
  • how to modulate the vestibular system (Arkwright, 1998).

Proprioceptors in the skin, joints and muscles are assisted by Golgi tendon receptors and muscle spindles, which detect the amount of tension in skeletal muscles and tendons, whether they are at rest or in motion.

It is the entire proprioceptive system that uses the forward/backward function to create an itch on the body (without an insect being present), which prompts you to touch that part of the body when the brain has temporarily lost awareness of a body part.  It is also the proprioceptive system that keeps on prompting touch after the amputation or loss of a body part. The sensation in the lost body parts tends to continue until the ‘map’ of the body in the brain, has been updated. The proprioceptive system, therefore, acts as an internal sense of self with a body map in the brain that allows internal awareness and appropriate movement, without conscious thought.

The vestibular system

The vestibular system is located in the inner ear and is one of the oldest systems in the body; being fully functional at 16 weeks in utero (Goddard, 2002). It comprises of the vestibule (Utricle and Saccule) and the three semi-circular canals (Rhoades & Tanner, 1995).

The semi-circular canals are three tiny, fluid-filled loops in the inner ear and are linked to two chambers, called the Utricle and Saccule. When the head is moved, the fluid in the three semi-circular canals and cavities lag a little, pulling on the hair detectors which tell the brain what is going on. The canals can tell whether you are nodding, shaking your head, or moving. The Utricle and Saccule can tell if you are tilting your head, and if movement is speeding up or slowing down.

In practical terms, the vestibular system works like a snow globe and spirit level rolled into one, to monitor and detect any movement of the head and/or of the environment. Any movement of the head unsettles the snow and sends the bubbles off-centre, alerting the brain to the need for adjustment to prevent you from falling over. Early in life the brain responds with the help of primitive reflexes; and later in life it uses postural reactions to maintain posture and prevent falling over.

When the vestibular system is working ineffectively, performance may be erratic and dyslexia, dysgraphia, mirror writing, or any of the other barriers to learning listed above, may be experienced. This is clearly observed by monitoring a person in a gravity free environment, such as an aeronaut in space. It has been reported that educated and literate aeronauts start to write from right to left, reverse numbers and letters, and even produce mirror writing, which according to Goddard (2002), demonstrates the significance of gravity and balance for spatial orientation and directional awareness.

To ponder: Could this mean that a child who struggles with number and letter reversals, who writes mirror image, and who finds spelling, reading and writing difficult, may be a child with a vestibular problem?

According to Arkwright (1998) the vestibular system:

  • maintains the muscles and posture of the body to move efficiently;
  • maintains a stable visual field by adjusting eye and neck muscles to compensate for movement of the head and body; and
  • provides a foundation for higher level of learning.

At the Mind Moves® Institute the role of effective proprioceptive and vestibular systems has been found to positively influence:

  • sensory integration
  • muscle tone
  • motor planning and
  • praxis.

The proprioceptive and vestibular systems in turn rely on kinesis to anticipate action and to initiate muscle tone. 

Kinesis

Kinesis is a term used to describe the process that takes place just before a muscle response becomes involved. It is the part of the inside senses which anticipates the required change in muscle tone to prevent you from falling over; going too fast; applying too much pressure; initiating and adjusting movement; maintaining balance; relaxing; or letting go; etc. Kinesis enables you to determine how much force is needed to throw a ball or to put a glass down without banging it on the table.

To ponder: Could that mean that a child who struggles to sit still may be a child who needs to move in order to activate his proprioceptive and vestibular systems, to become aware of his various body parts and their relation to each other, to complete his body map?

  1. MOVEMENT, MUSCLE TONE, BALANCE & LEARNING

The interaction between the proprioceptive system, the vestibular system, and kinesis is associated with movement that maintains the body in an upright position. Movement occurs on three planes, which means that three midlines are crossed:

  • the midline between front and back parts of the brain and body (Moro reflex);
  • the midline between top and bottom parts of the brain and body (TLR reflex); and
  • the midline between the left and right sides of the brain and body (ATNR reflex).

Gross motor movement starts as early as 5 weeks in utero, prompted by primitive reflex reactions, to activate the inside senses in a gravity free environment. Over time, these inside senses contribute to the development of muscle tone, crossing the midlines, and balance. Each primitive reflex initiates a new neurological pathway, enabling the different senses and the nervous system to communicate effectively with each other, in a progressively more complex manner.

To assist in this process, the vestibular nerve begins to myelinate in utero by registering the movements of the fetus and its environment (uterus). This is necessary for the baby’s survival outside the uterus (Hogan, 2004). Outside the uterus, the pull of gravity presents an added challenge. These basic in utero movement patterns serve as the ‘blueprint’ for movements needed to oppose the force of gravity once born.

Muscle tone is an opposing force to gravity; and through repetitive movement patterns (reflex reactions), muscle strength, coordination, and control are developed. The more the body weight, the more the muscle tone that is needed to oppose the pull of gravity – in a resting position, static position, as well as during movement.

To ponder: Could a discrepancy between body weight and muscle tone be the reason why overweight babies battle to crawl?

May that also be the reason why overweight babies, children and adults find it so difficult to start any movement program or participate in sport and dance?

  1. MOVEMENT & MIDLINES

The constant crossing of the three midlines starts off with gross motor movements, and over time refines to become more controlled fine motor movements. The constant fight against the pull of gravity and the continual crossing of the midlines, stimulates the development of muscle tone from top to toe (cephalo-caudal) and from inside to outside (proximal-distal). Balance is only possible if you have sufficient muscle tone to simultaneously hold the body in the centre of all three midlines.

Can you remember learning to ride a bike, how much easier it was to ride than to start and stop? Children with poor balance, low muscle tone and midline problems, concentrate and cooperate better when they are on the move. Teachers and parents can help these children by offering movement opportunities in class or while doing homework, to develop their inside senses so they too can sit still and straight, and use the biggest portion of their concentration for the task at hand.

These movement opportunities:

  • activate their proprioceptive and vestibular systems
  • encourage crossing the midlines
  • improve muscle tone.

This in turn:

  • develops sensory integration
  • improves concentration
  • maintains static balance (sit still)
  • organises the flow of information to facilitate learning.

Once the balance system (proprioceptive system, vestibular system and kinesis) is effective, these children feel more in control of themselves and their behaviour, which aids greatly in concentration, the development of confidence and a positive sense of self.

  1. WHAT CAN YOU DO

You may need to consult with a neuro-developmental physiotherapist, an occupational therapist with Sensory Integration training, or a movement specialist such as an Advanced Mind Moves Instructor, to tailor make and implement a structured movement program. It would be helpful if the movement programme focusses on developing a more efficient balance system. Once efficient, the balance system would manage movement more spontaneously. As muscular control improves, it has been found that the need for movement (to maintain balance) will decrease.

The most advanced level of movement is the ability to stay totally still. Perfect balance is the action of not moving. Rowe

Mind Moves is an example of a movement program designed for use in class and at home. The movement activities are simulations of the natural primitive reflex actions, with the purpose of activating the primitive reflexes to complete their function of developing specific neurological pathways. Once these pathways have been established through repetitive use, the primitive reflexes tend to integrate and go to rest. Integrated primitive reflexes become part of the survival responses, and the thinking brain is then freed to pay attention to higher cognitive functions, like learning the ABC, knowing left from right, telling time, numeracy skills, reading with comprehension, etc.

Each primitive reflex introduces a new neurological pathway, enabling the different senses and the nervous system to communicate effectively with each other, in an increasingly more complex manner. Each primitive reflex adds a dimension to the constantly developing sensory-motor system to improve a child’s ability to cross the midlines, improve muscle tone, and establish balance.

Once a primitive reflex has fulfilled its function, it becomes inhibited, and ready to resurface and repair or reconstruct its pathway if injury or trauma occurs.

Movement moulds the brain. Repetition makes it efficient.

  1. SUGGESTED MOVEMENT PROGRAMME

  • Participate daily in activities that promote movement, like sliding, swinging, going on the round-about, bouncing on a trampoline, roller blading, ice skating, skateboarding, scooter boarding, climbing a jungle gym, spinning, riding a tricycle/bicycle up and down a ramp, etc.
  • Play ‘old-fashioned games’, like ring-a-rosy, leap frog, tag, Marco Polo, musical chairs, statues, etc.
  • Embark on a movement programme such as Mind Moves (De Jager, 2019a).  First determine a goal – be clear about what you want to achieve (your expected outcome). For example, to improve crossing the midline, to improve muscle tone, or to sit still in class. Secondly, select the appropriate Mind Moves. Do the moves slowly and with control, before school, when needed in class, and before doing homework. Repeat each move at least three times and notice changes in posture, muscle tone, balance, coordination, confidence and a sense of self. Celebrate every improvement.

Mind Moves to stabilise the base

A child develops from head to toe, the head must therefore stabilise before the trunk. A stable head is important because the head leads all physical development. Think of a baby – once the baby can keep its head up, rolling, sitting and crawling naturally follows.

Neck flexor: Maintain the spine in a “string of beads” position throughout this move.

Place the palm of the hand against the forehead, pushing firmly for a count of eight. Remember to breathe. Alternate the position to the back of head, the left and the right side of head, repeating the process first with one hand, and then the other. This movement strengthens and relaxes the neck and shoulder muscles to isolate head movement from body movement, and in so doing inhibits the Tonic Labyrinthine Reflex (TLR). It also improves posture, listening skills, balance, and muscle tone.

Trunk rotator: Lie flat on the back, spread the arms wide, and raise the knees to hip level. Slowly rock the knees to the left until the left knee touches the floor, and then to the right until the right knee touches the floor. The shoulders and lower back should stay glued to the floor. This move strengthens the core muscles, while separating the shoulder action from the hip action, to promote sitting, focus, and concentration. It also forms the basis for crossing the lateral midline.

Homolateral walk: Move the left arm and left leg together, then the right arm and right leg. Follow with a Bilateral walk, touching the left hand to the right knee.

Mind Moves to cross the midlines

There are three midlines between left and right, front and back, as well as top and bottom of the body. These three midlines also exist in the brain between the left and right brain, the sensory back brain and the front or motor part of the brain, the thinking, top part of brain and feeling, bottom part of the brain. To improve crossing these midlines, a child must move across all the midlines kinaesthetically (with whole body like in Trunk Twister), auditory (as in Neck Rotator) and visually (as in Mouse Pad).

Trunk twister: Stand with legs shoulder width apart, upper body dropped forward and arms hanging down. Start rotating slowly, from right to left, creating a circle with the body and arms. Stop to change direction, rotating from left to right, creating as big a circle as possible. It may be easier to do the exercise sitting down at first to prevent falling over. This move provides vestibular stimulation, which strengthens balance, muscle tone, and spatial orientation. It also promotes crossing the midlines, to improve appropriate action and task completion.

Neck rotator: Stand up. Imagine the neck and spine are a string of beads. Pull at the imaginary string above the head, until the beads hang in a straight line. Slowly turn the head as far to the left as possible, hold it in the extended position for a count of eight. Then slowly turn the head as far to the right as possible, and hold it in the extended position for a count of eight. The hips and shoulders should face forward while the head rotates. This move relaxes the tension in the neck and shoulders, to free up eye movement and improve listening skills.

Mouse pad: The eyes are to the brain what the mouse is to the computer. The eyes access different parts of the brain when turning up, down, horizontal, left, and right. Focus on the thumb held at elbow distance from the eyes. Move the thumb upwards, first around the left eye, and then around the right eye. Repeat five times. Swop hands and repeat the same process, always first drawing a circle around the left eye and then around the right eye.

Mind Moves to improve muscle tone

Muscle tone is an opposing force to gravity; and through repetitive movement patterns muscle strength, coordination, and control can be developed. The heavier the body, the less likely the child would want to move, because more muscle strength and tone are needed to oppose the pull of gravity. Muscle tone is a near-sensory function and its control centre is in the inner ear.

Antennae adjuster: Massage both ear lobes simultaneously from top to bottom using circular massage movements.

Temporal toner: Start in front of the ears, using both hands simultaneously. Gently tap upwards around the ears. This movement promotes temporal lobe stimulation to improve listening skills, auditory perception, vestibular stimulation, proprioception, and balance. It also promotes integration between listening and communicating, both in verbal and written form.

Gravity crawl: Crawl on a carpet or grass, keeping the tummy flat on the floor, while the arms and legs bend to propel the body forward. Leopard crawl on a flat surface as well as up and down a slope. This movement aids core muscle development, muscle tone, and vestibular stimulation. It also promotes posture and whole-body coordination for writing and sport.

We can give children the desire to succeed at things we want to teach them – by making early learning experiences interesting, successful and fun. Forcing academic tasks on unready brains, risk extinguishing the candle of intellectual excitement, particularly for children who are on different developmental timetables. Nobody wants to enter an arena where he has repeatedly suffered a knock-out punch. Healy

 

Arkwright,N. 1998. An introduction to Sensory Integration. San Antonio, Texas: Therapy Skill Builders.

Ayres, J. 1980.  Sensory Integration. Los Angeles: Western  Psychological Services.

Blythe, P. & McGlowd, D.J. 1979. An organic basis for neurosis and educational difficulties. Chester, UK: Insight Publications.

Converse, D. Rock-A-Bye Baby: Why Movement is Important. Hillsborough County Family and Consumer Sciences Newsletter. November 2004. http://hillsboroughhcs.ifas.ufl.edu/

De Jager, M. 2013. Play Learn Know. Welgemoed: Metz Press Publishing.

De Jager, M. 2017a. BabyGym – brain and body gym for babies. Cape Town: Metz Press Publishing.

De Jager, M. 2017b. Play Learn Grow. Johannesburg: Mind Moves Institute Publishing.

De Jager, M. 2019a. Mind Moves – removing barriers to learning. Johannesburg: Mind Moves Institute Publishing.

De Jager, M. 2019b. Brain development MILESTONES and Learning. Johannesburg: Mind Moves Institute Publishing.

De Witt, M.W. & Booysen, M.I. 1994. Die Klein Kind in Fokus. Pretoria: Acacia Books.

Ganong, WF. 1995. Review of Medical Physiology (17th ed). Connecticut: Prentice-Hall International Inc.

Goddard, S. 2002. Reflexes, learning and behaviour. Oregon: Fern Ridge Press.

Hogan, K. 2004.The Ear and the Alexander Technique. http://www.kayhogan.com

Levinson, H.D. 1984. Smart but feeling dumb. New York: Warner Books Inc.

Marieb, E.N.  2000. Essentials of Human Anatomy & Physiology (6th ed). San Francisco: Benjamin/Cummings Science Publishing.

Rhoades, RA & Tanner, GA.  1995.  Medical Physiology.  Little Boston: Massachusetts.

Sears, W; 1989. Wearing your baby. http://www.findarticles.com