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Do You Really Know About Child Development And Milestones?

Early childhood is characterized by rapid development, which is often monitored through the assessment of primitive reflexes and developmental milestones. Primitive reflexes are temporary reflexes that disappear after approximately one year of life. Abnormal or persistent primitive reflexes are suggestive of neurological or musculoskeletal pathology and should prompt further evaluation. Developmental milestones are the physical, intellectual, and behavioral skills a child is expected to acquire by certain ages. These milestones should be assessed at every well-child visit and whenever there is a concern for abnormal development. If the assessment is abnormal, the child should promptly receive further evaluation and/or relevant referrals.

Primitive reflexes

  • Primitive reflexes are reflexes that are normally present during infancy and disappear with the development of inhibitory pathways to the subcortical motor areas (usually within the 1st year of life)
  • Primitive reflexes persistence
    • In children; : indicates impaired brain development
    • In adults; : suggests frontal lobe lesions; (frontal release signs)
ReflexDescriptionAge of resolutionClinical significance
Moro reflexHolding an infant in the supine position while supporting the head, then allowing the head to suddenly fall back elicits abduction and extension of the infant’s arms and elbows, followed by their flexion. 3–6 monthsUnilateral absent
ipsilateral brachial plexus injury
Ipsilateral fractured clavicle
Bilateral absence indicates brain injury (e.g., due to birth asphyxia, intracranial hemorrhage) or bilateral brachial plexus injury
Rooting reflexStroking the cheek elicits the turning of the head towards the stimulus and opening of the mouth.4 monthsUnilateral absence indicates peripheral injury

Bilateral absence or premature resolution
Perinatal asphyxia
Intracranial hemorrhage
Sucking reflexTouching the roof of the mouth elicits a sucking motion.4 monthsUnilateral absence indicates peripheral injury

Bilateral absence or premature resolution
Perinatal asphyxia Intracranial hemorrhage
Palmar graspStimulation of the palm elicits a grasping motion.3–6 monthsUnilateral absence
Brachial plexus injury
Peripheral nerve injury
Bilateral absence of the reflex at birth may indicate cerebral palsy.
Plantar graspStimulation of the sole elicits curling of the toes (plantar flexion).12 months Bilateral absence: suggestive of cerebral palsy.
Plantar reflexStroking the sole of the foot from heel to toe elicits dorsiflexion of the foot with the concomitant extension of the big toe and fanning of the other toes.12–24 monthsPersistence or reappearance after 24 months indicates an upper motor neuron lesion (Babinski sign).
Stepping reflexHolding the infant upright with feet on the examination table elicits a stepping motion with alternating flexion and extension of the legs.2 monthsInfants born at term step from heel to toe. Preterm infants tiptoe.
Galant reflexHolding the infant in the prone position and stroking it on one side of the paravertebral region elicits flexion of the lower back and hip towards the stimulus.2–6 monthsPersistent Galant reflex might be associated with bed-wetting  
Asymmetrical tonic neck reflex (ATNR)Turning the head to one side elicits extension of the arm and leg on the side the head is facing and flexion of the contralateral arm and leg (fencing posture).3–4 monthsThe ATNR aids in the development of hand-eye coordination. 
Glabellar tap signTapping the glabella elicits blinking.4–6 monthsThe persistent glabellar tap sign is a frontal release sign called the Myerson sign. 
Landau reflexPlacing the infant in a prone position elicits arching of the back and raising of the head.24 monthsNone
Snout reflexTapping or applying light pressure to closed lips elicits puckering.4 monthsNone
Parachute reflexHolding the infant in an upright position, followed by sudden lowering towards the examination table elicits the extension of the infant’s arms. This reflex appears at 6–9 months of age.PersistsInfants suffering from neonatal encephalopathy may show an asymmetric or absent parachute reflex
the photo from GrepMad

Developmental milestones

The age at which a child should reach a particular milestone may differ slightly depending on the care specifics in different countries and cultures. The milestones listed in the tables below are valid in the US.

AgeGross motorFine motorLanguageSocial/Cognitive
2 monthsRaises head and chest when proneFollows objects past the midlineCoosSmiles back (social smile)Recognizes parents
4 monthsHolds head straight
Rolls over the front to back

Props himself/herself up on wrists in the prone position
Holds and shakes rattleLaughsMakes consonant soundsLocalizes sound 
6 monthsSits without support
Rolls over back to the front
Grabs and transfers objects from one hand to the otherRaking grasp BabblesDevelops stranger anxiety (6–9 months) Develops object permanence (6–9 months)
9 monthsCrawlsStands when holding on to somethingPincer grasps (9-12 months) Says “ma-ma,” “da-da”Orients to nameImitates actions separation anxiety (considered normal until 3 years of age) [13]
12 monthsStarts to walk throw objectsPoints at objectsKnows 1–5 wordsFollows simple commands (e.g., “Come to mommy”.)

Common developmental behaviors

Certain temporary pediatric behaviors are considered normal parts of cognitive, imaginative, and creative development, e.g.:

  • Stranger anxiety: when an infant is fearful of unknown individuals
    • Expected ages: 6 months–3 years 
    • Clinical features: crying and/or clinging to a known caregiver when around strangers
  • Separation anxiety: when an infant or young child is afraid of being separated from their caregiver
    • Expected ages: peaks between 9 and 18 months and resolves by 3 years of age  
    • Clinical features
      • Crying and/or clinging to a caregiver if the caregiver tries to leave
      • Continued crying after a caregiver has left
  • Pretend to play: when a young child imitates adult activities and/or interactions [20]
    • Expected ages: starts around 15–18 months
    • Examples
      • The use of real or toy items to imitate activities 
      • Symbolic play: the use of an item to represent other things 
    • Benefits: enhances creativity and provides practice for social skills, emotional regulation, and language development 
  • Magical thinking: when thoughts are believed to affect change and nonrelated events are causally linked [21][22]
    • Expected ages: ∼4–5 years
      • Decreases with age
      • Some persistence into adulthood may occur.  
    • Examples
      • Assuming their actions cause unrelated events 
      • Attributing emotions to an inanimate object 
      • Believing that wishing for something causes it to come true
  • Imaginary companion (IC): when a fictitious human, animal, or object is treated as if it were alive
    • Expected ages: Preschool and young school-aged children  
    • Benefits are similar to those of pretend play. 
The photo on WiKi


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