When a child is born, the earliest parts of the brain that start to develop are the primitive reflexes. They are present during the first few months of life to help with survival, but within the first year are replaced by postural reflexes instead. Plainly speaking, the forebrain begins to inhibit the hindbrain and these postural reflexes are a more mature response that control balance, coordination, and sensory motor development. This process helps a child reach developmental milestones on time.
If these primitive reflexes are not inhibited correctly then they can contribute to issues like poor sleep, energy levels, impulse control, balance, coordination, immunity, sensory perceptions, poor motor control and fine motor skills. This sequela of events can lead to a child being given labels like ADHD, ASD, SPD, global apraxia, and other learning disabilities. Not only do we see these retained primitive reflexes contributing to symptoms listed above but can also contribute to all levels of social, emotional, and intellectual learning.
There can be several reasons for the retention of primitive reflexes. The birth process is a key factor so a C-section birth or traumatic birth could contribute to their retention. Falls, hitting the head, lack of tummy time and emotional traumas can be a factor as well. There can also be underlying metabolic dysfunction that can make it difficult for neurons to grow and the postural reflexes to develop, so a mother’s health during pregnancy is something to consider as well.
There are 8 primitive reflexes that will be discussed. Key features like what the primitive reflexes are responsible for, as well as how to test for any retained primitive reflexes.
Moro – The Moro reflex acts as a baby’s primitive fight/flight reaction and is typically replaced by the adult startle reflex by four months old. If a child experiences a retained Moro reflex beyond 4 months, they may become over sensitive and over-reactive to a sensory stimulus resulting in poor impulse control, sensory overload, anxiety and social immaturity. Some additional signs of a retained Moro reflex are motion sickness, poor balance, poor coordination, easily distracted, unable to adapt well to change, as well as mood swings. While the child’s eyes are closed or looking away, an adult can clap their hands by the child’s ear. If the noise startles them and they flail their arms outward, this is a sign of a retained reflex. Also, if a child tries to stand on one leg and has poor balance and falls over this can be another positive sign.
Rooting Reflex – The rooting reflex assists in the act of breastfeeding and is activated by stroking a baby’s cheek near the corner of their mouth, causing the baby to turn and open her mouth. Retention of the rooting reflex beyond four months may result in difficulty with solid foods, poor articulation, and thumb sucking.
Palmar Reflex – The palmar reflex is the automatic flexing of fingers to grab an object and should integrate by six months. If the palmar reflex is retained, a child may have difficulty with fine motor skills, stick their tongue out while writing and exhibit messy handwriting. They may also have speech and language problems and even anger issues. This child may also have trouble holding pencils and markers in the traditional tripod grip. If a parent strokes the child’s palm with a paintbrush (or lightly with a fingertip) the fingers should not flex. If their hand flexes this is a sign the reflex is retained.
ATNR – Asymmetrical tonic neck reflex (ATNR) is initiated when laying babies on their back and turning their head to one side. The arm and leg of the side they’re looking should extend while the opposite side bends. This reflex serves as a precursor to hand-eye coordination and should stop by six months. Ask the child to get on all fours with the arms straight, fingers pointing forward and the head in neutral. With their weight over their hands, the parent rotates the child’s head left or right. If their elbow bends on the opposite side of head rotation or the weight shifts posteriorly (i.e. off the hands) then the reflex is probably present.
Spinal Galant Reflex – The Spinal Galant reflex happens when the skin along the side of an infant’s back is stroked, the infant will swing towards the side that was stroked. This reflex helps with the birthing process and should inhibit between three and nine months. If it persists, it may affect a child’s posture, coordination, attention and ability to sit still. Retention of the spinal Galant reflex is also associated with bedwetting. With the child on all fours, lightly stroke down one side of the lumbar spine towards the hips. If they move their back (typically arching or away from the stroke) then the reflex is probably present.
TLR – The tonic labyrinthine reflex (TLR) is the basis for head management and helps prepare an infant for rolling over crawling, standing, and walking. This reflex initiates when you tilt an infant’s head backward while placed on the back causing legs to stiffen, straighten and toes to point. Hands also become fisted and elbows bend. It should integrate gradually as other systems mature and disappear by 3 1/2 years old. If retained, the TLR can lead to poor muscle tone, tendency to walk on toes, motion sickness, and poor balance. To test this reflex, have the child stand straight with his feet together. Have them close their eyes and then look up for several seconds and then look down for several seconds. Make sure that you have your hands ready to catch the child in case they fall. Notice any swaying or movement, locked knees or holding of breath when the head is tilted either up or down, all which are indicators of a retained TLR.
Landau Reflex – The Landau reflex assists with posture development and technically isn’t a primitive reflex as it isn’t present at birth. It is when a baby lifts his head up causing the entire trunk to flex and typically emerges at around 3 months of age. It is fully integrated by one year. If the landau reflex persists beyond this point, children may experience short-term memory problems, poor motor development, and low muscle tone. When holding the infant face down in the air, the baby’s legs will arch up if the head is up and drop down if the head is lowered. This is normal up to about 1 year. If it persists past one year of age, this means the reflex is retained.STNR – Also known as the crawling reflex, symmetrical tonic neck reflex (STNR) is present briefly after birth and then reappears around six to nine months. This reflex helps the body divide in half at the midline to assist in crawling – as the head is brought towards the chest, the arms bend and legs extend. It should disappear by 11 months. Developmental delays related to poor muscle tone, tendency to slump while sitting, and inability to sit still and concentrate can result if the STNR is retained. Usually, this can be a child that skips crawling. With the child on all fours with the weight forward over their hands, the parent flexes the neck fully (looking down) and holds for 5 seconds, then slowly extends the neck (looking up) and holds for 5 seconds. Repeat 3 times. If the child alters their body position by shifting their weight backwards, flexing their elbows, or arching their back then the reflex is probably present.