What Are Examples of Infantile Primitive Reflexes?

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Patient Presentation
A 2-month-old female came to clinic for her health supervision visit. The parents were pleased with how well she was growing. “She’s amazing,” said her dad, “She can even walk,” and he proceeded to show the pediatrician how she would lift her feet and place them slightly forward when she was held upright. The past medical history showed a full term infant without prenatal or natal problems.

The pertinent physical exam revealed normal growth parameters in the 75-90%. She had a social smile. She had good tone and strength. Cranial nerves were intact and deep tendon reflexes were normal for age. She had a positive Babinski reflex. The pediatrician also pointed out other normal primitive reflexes including the Moro reflex, Asymmetric Tonic Neck reflex, Stepping and Placing reflexes as well as Galant and Perez. The diagnosis of of a healthy infant was made. “You’ll notice some of these reflexes for a while and then they will go away as her brain matures. Right now they show that she is doing well,” the pediatrician remarked. The parents smiled approvingly.

Discussion
As part of the normal developmental process of central nervous system maturation, primitive reflexes (i.e. infantile automatisms) occur which are automatic movement patterns which can begin during fetal development and continue after birth. Some appear important for human survival such as rooting and sucking to obtain nutrition. Others may be phylogenetic remnants. Primitive reflexes are present and disappear at predictable times and therefore can assist in evaluation of infant development. There is a range of normal and some can persist to older ages in some individuals. Primitive reflexes that occur before or after predicted times or that present asymmetrically on the body can potentially show abnormalities and therefore are important to note. Children and adults with various brain injuries or diseases also may show some of these primitive reflexes.

Learning Point
Examples of primitive reflexes include:

  • Rooting reflex
    • Mouth or cheek touched and infant turns head to that side
    • Present at birth
    • Disappears around 3-4 months, but can be seen in sleeping infants until 7-8 months
  • Sucking reflex
    • Sucking begins when nipple placed in infant’s mouth, or examiner’s finger is placed at the commissure of infant’s mouth
    • Present at birth
    • Disappears around 3-4 months, but can seen in sleeping infants until 7-8 months
  • Moro or Startle reflex
    • Infant is surprised/startled and the four limbs abduct and extend then abduct and flex. Infants will also extend the spine initially and then close the fingers. Startle is elicited by striking surface on either side of infant (original method by Moro), loud noise, or lifting the infant head and shoulders above body and allowing the head to drop (of course with support).
    • Present at birth, can be seen as early as 25 weeks gestation and is elicited by 30 weeks
    • Disappears around 3-4 months but normal up until 6 months
  • Stepping reflex
    • Infant held upright and slightly forward with feet on surface will raise legs and look like stepping or walking
    • Present at birth
    • Disappears around 2-3 months
  • Placing reflex
    • Infant held upright and dorsum of foot is touched by the edge of table. Infant lifts foot and places it on the table
    • Present at birth
    • Disappears by first year
  • Palmar grasp reflex
    • Examiner’s finger placed in infant palm at base of fingers and press applied. Infants finger’s flex to grasp the examiner’s finger. There are 2 phases – the catching of the examiner’s finger and the holding of the examiner’s finger
    • Present at birth, can be seen as early as 28 weeks gestation
    • Disappears by 6 months
  • Plantar grasp reflex
    • Examiner’s finger placed in infant sole at base of toes and press applied. Infants toes flex to curl around the examiner’s finger. There are 2 phases – the catching of the examiner’s finger and the holding of the examiner’s finger.
    • Present at birth
    • Disappears by 15 months
  • Babinski reflex
    • Pressure applied to sole of foot along the lateral edge starting with the heel and curving around to the base of big toe. Normal or negative is to have downward curving of the toes or no movement. A positive Babinski reflex, that of the toes curving upward, is normal in infants because of their immature neurological status.
    • Present at birth
    • Disappears by 1-2 years
  • Landau reflex
    • Infant is placed face down on a surface or in lateral suspension and the infant lifts its head and extends its legs
    • Present starting at 3 months
    • Disappears by 2 years
  • Blinking or Glabella reflex
    • Glabella is lightly tapped and both eyes blink. Habituation occurs with multiple attempts of the tapping
    • Present at birth
    • Disappears by 1 year
  • Asymmetric tonic neck reflex
    • With infant in supine position, head is gently rotated to one side. Extension of the lateral arm and flexion of the contralateral arm occur. This position is sometimes called the Fencer’s position.
    • Present around birth
    • Disappears by about 6 months
  • Symmetric tonic neck reflex
    • With infant in supine position, head is gently flexed. Extension of the head, arms and legs occurs
    • Present around 2 months
    • Disappears about 6-9 months
  • Parachute reflex
    • Infant prone in air and brought to the surface with the head down. Infant reacts as if trying to cushion a fall with their arms abducted and extended and fingers spread.
    • Present around 8-9 months
    • Present throughout life
  • Gallant reflex
    • Infant head prone in air and one side of lower spine lightly stroked. Infant’s spine contracts on that side causing the hips to move laterally on the side stroked (e.g. spine incurves).
    • Present at birth
    • Disappears around 2-4 months, up to 6 months
  • Perez reflex
    • Infant head prone in air and both sides of lower spine lightly stroked. Infant extends hips and legs.
    • Present at birth
    • Disappears around 2-4 months

Questions for Further Discussion
1. What do decerebrate and decorticate postures look like? What do they mean?
2. What informal or formal developmental evaluations do you carry out in the office?
3. What are indications for referral to a neurologist or developmental pediatrician?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Infant and Newborn Care and Infant and Newborn Development.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Futagi Y, Toribe Y, Suzuki Y. The grasp reflex and moro reflex in infants: hierarchy of primitive reflex responses. Int J Pediatr. 2012:191562. doi:10.1155/2012/191562

Gieysztor EZ, Choinska AM, Paprocka-Borowicz M. Persistence of primitive reflexes and associated motor problems in healthy preschool children. Arch Med Sci AMS. 2018;14(1):167-173. doi:10.5114/aoms.2016.60503

Salandy S, Rai R, Gutierrez S, Ishak B, Tubbs RS. Neurological examination of the infant: A Comprehensive Review. Clin Anat N Y N. 2019;32(6):770-777. doi:10.1002/ca.23352

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa

Published