Like any reflex, primitive reflexes are automatic, unconscious reactions to stimuli.
In the womb and early stages of life, we are equipped with a number of reflexes that not only aid the birthing process, but are also a baby's tool-kit for survival and early learning during the first year of life. For example, I am sure you still remember that overwhelming joy at seeing your baby rooting and sucking for the first time and how, when you placed your finger in their tiny hand, they were able to grip it tightly. These automatic, stereotypical movements made by newborn babies are called primitive reflexes. They are instinctive, involuntary reflex movements that require no thought and are directed from the brain stem. They are vitally important to a baby's birth, survival and learning. Without the appropriate rooting and sucking reflexes, for example, a baby will not have the ability to suck properly, therefore making effective feeding very difficult.
Every primitive reflex triggers, or is triggered by, a physical reaction. For example: if you blow in a baby's face it will blink; a sudden loud movement will startle and make it cry; or placing a finger in a baby's open palm will cause the baby to grasp the finger. As a baby grows, these reflexes should mature and start to weaken through movement and eventually integrate or 'go to sleep'. This allows the Postural Reflexes to develop along with related motor skills, like sitting, crawling, walking, running and jumping. If, for any reason, there is a deficit of normal movement, primitive reflexes, with their associated complications, may remain and postural reactions may not fully mature.
This can lead to difficulties with not only subsequent motor development, but also perceptual skills, the visual functioning needed for reading and the hand-eye co-ordination needed for writing. The presence of primitive reflexes and the lack of postural reflexes provide evidence of neuro-motor and sensory immaturity in the functioning of the central nervous system, which can act as a barrier to learning and lead to behavioural problems such as concentration difficulties, frustration, poor impulse control and general underachievement.
The following reflexes are the ones most often retained:
The Moro Reflex, sometimes called the infants' startle reflex, acts as a baby's fight-or-flight response. A sudden bright light, change in temperature, loud noise, touch or change in body position can activate the Moro Reflex. Its role as a survival mechanism in the first months of life is to alert, to arouse and to summon assistance. The Moro Reflex should be replaced by the adult startle reflex by 2-4 months of age.
Possible long term effects of a retained Moro Reflex:
- Constant fight-or-flight mode
- Easily triggered anger or emotional outbursts
- Over-anxiety & dislike of change
- A need to control situations
- Better interaction with younger children than with their peers
- Shyness, low self-esteem and weak ego
- Difficulty with balance and sport, particularly ball games
- Difficulty with reading and writing
- Stimulus bound: difficulty ignoring surrounding visual and auditory stimuli, (e.g. shutting out background noise), a need to pay attention to everything, affecting concentration and attention
- Hypersensitivity to both light and sound
- Weak immune system, prone to allergies and infections
- Sensitivity to certain foods, picky eater
The TLR is activated by movement of the head, both forwards and backwards. When a baby's head is brought forward, the whole body - arms, legs and torso - curls inwards into the characteristic foetal position. When the head moves backwards, the whole body straightens and extends. The Tonic Labyrinthine Reflex helps an infant to start to defy gravity and master neck and head control outside of the womb. It should be completed by three and a half years of age
Possible long term effects of a retained TLR:
- Postural problems, specifically hyper- or hypo-tonus (muscle tone)
- A tendency to walk on the toes
- Problems with balance and co-ordination
- Motion sickness
- Orientation and spatial difficulties
- Oculo-motor problems (e.g. tracking or following objects, hand-eye co-ordination)
- Visual-perceptual problems, spatial problems
- Poor sequencing skills
- A dislike of sporting activities
- Poor sense of direction
- Fear of heights
- Difficulty learning to tell time
The STNR helps prepare an infant to push itself up off the ground from the prone position in preparation for crawling on hands and knees. It is activated by movement of the head up and down, which automatically results in movement in the arms and legs. When the head is lifted up, there is extension in the upper limbs accompanied by flexion in the lower limbs. When the head is lowered, the limbs of the upper body flex and lower limbs extend. In normal development, most babies pass through a phase of rocking backwards and forwards on their hands and knees at around 8-11 months old, helping to integrate this reflex before learning to crawl.
Possible long term effects of a retained STNR:
- Poor integration of upper and lower body resulting in, for example, difficulty in learning to swim
- Poor sitting posture: a tendency to slump when sitting at a desk or a table, to sit with legs tucked under or wrapped around legs of chairs, 'W' sitting
- Poor attention and concentration when sitting &/or a preference to work while lying on the floor
- Poorly developed or weak muscle tone
- Poor hand-eye co-ordination
- Difficulty with visual accommodation, e.g. copying from the blackboard, catching a ball, etc.
- Impaired vertical visual tracking: the ability to read/align columns or track an object moving slowly in a vertical direction
- Messy eating
The ATNR is activated when a baby turns their head to one side. The arm and leg on the jaw side automatically straighten and the limbs on the opposite side flex. This reflex is thought to have an important role to play in not only the birthing process, but also early hand-eye co-ordination and distance perception. The Asymmetrical Tonic Neck Reflex should be inhibited by 6 months of age in the waking state. If it remains active, it can significantly impact a child's academic performance and ability to function well in school.
Possible long term effects of a retained ATNR:
- Difficulty with the ability to control the arm and hand when writing, resulting in poor handwriting, immature pencil grip, a tendency to use excesseive pressure on writing implements, etc.
- A tendency to rotate paper or page by 90 degrees when writing to compensate for the reflex
- Difficulty crossing the vertical midline: for example, a right-handed child may find it difficult to write on the left side of the page
- Discrepancies between oral and written performance
- Poor development of lateral eye movements, such as visual tracking (necessary for reading and writing)
- Impaired control of automatic balance
- Affected bilateral integration: the differentiated and integrated use of the two sides of the body
- Continued cross laterality or ambiguity of laterality beyond 8 years of age
These are only some of the reflexes that might be involved in specific learning difficulties and behavioural problems. More than two reflexes must be present before a diagnosis of Neuro Developmental Delay is considered.
Further recommended reading:
Reflexes, Learning & Behavior: A Window into the Child's Mind, by Sally Goddard. Published by Fern Ridge Press: ISBN 0-9615332-8-5