Primitive reflexes

1. Session 3: Primitive Reflexes

2. LEARNING OUTCOMES
By the end of this session, you will be able to:
1. Be familiar with the primitive reflexes present in the baby at birth,
2. Identify which of these reflexes are relevant to the neurological
examination of the baby,
3. Be able to explain the role of the primitive reflexes,
4. Be able to explain the disappearance/integration of these reflexes,
5. Be able to explain the clinical significance of the reappearance or
persistence of the primitive reflexes.

3. What are the Primitive Reflexes?
• Automatic involuntary stereotypic movements in response to
particular stimuli directed from brainstem and spinal cord (no cortical
= thought involvement).
• Needed for NUTRITION, SURVIVAL, PROTECTION AND
DEVELOPMENT (in utero and early life)
• By time, they disappear or are integrated into voluntary movements
(inhibitory effect of maturing cortical centers) = neurological
organization of the brain.

4. What are the Primitive Reflexes?
• Most are present at birth (e.g. rooting & sucking reflexes).
• They emerge at the last 4 months in utero (late fetal period) and first
4 months after birth.
• Most disappear or integrate by 6 to 12 months age.
• Persistence or reappearance after 6 t0 12 months age = cortical or
cerebral damage. It will lead to impaired development of postural
control, achievement of milestones and volitional movements.

5. What is the Function of Primitive Reflexes?
1. Critical for human survival (NUTRITION, PROTECTION)
2. Development of future voluntary movement through integration
(DEVELOPMENT)
3. Diagnostic tools (age specific = determine level of neurological
maturation)
4. Diagnostic tools (persistence or reappearance or asymmetry = CNS
immaturity or dysfunction)

6. Why do we test these reflexes?
• Evaluate developmental status & integrity of nervous system and lack
of damage (normal course of appearance and disappearance)
• Indicate gestational age (if premature baby: they appear later and
disappear later than mature babies)
• Evaluate symmetry (bilaterally elicited). If asymmetric (unilateral only)
= unilateral pathology e.g. obstetric brachial plexus palsy)

7. Primitive Reflexes
1. Palmar Grasp
2. Rooting / Search
3. Sucking
4. Moro
5. Startle
6. Asymmetric Tonic Neck (ATNR)
7. Symmetric Tonic Neck (STNR)
8. Plantar Grasp
9. Spinal Galant

8. Primitive Reflexes
Primitive Reflexes Stimulus Response Duration Importance
Palmar Grasp Reflex Palm: When a finger/or
other stimulus into the
palm of the child’s hand on
the lateral aspect.
4 fingers (not thumb)
close: Fingers flex and the
child firmly grasps the
hand. Hand will relax and
open directly after
removal of stimulus
Appears in utero and
disappears 3 months
postpartum
- One of the most noticeable reflexes
- May lead to voluntary reaching / grasping
Pathological if tonic part of the reflex
(flexion) persists (denoting neurological
abnormality called spasticity. It causes
difficulty with releasing objects from hand
and hand activities and Interferes with the
development of voluntary grasp
Rooting - Search Reflex Touch cheek gently
touching the top lip, and
area of the face with your
finger.
Head moves toward
stimuli and open his
mouth
Appears in utero and
disappears 3 months
postpartum.
- Often in conjunction with sucking reflex.
- It contributes to head/body-righting
reflexes.
If no reflex or persistence may be sign of
CNS or sensorimotor dysfunction. If No
reflex problematic for nutrition persistence
hypersensitivity in the mouth and on the
lips may contribute towards a drooling,
Sucking Reflex touch of lips by placing a
clean gloved finger, bottle
teat or dummy in the
mouth and onto the tongue
Sucking action Appears in utero and
disappears 3 months
postpartum.
- Often in conjunction with searching reflex
- Premature babies often have a weak suck
reflex and subsequently need tube
feeding
- No reflex problematic for nutrition

9. Primitive Reflexes
Primitive Reflexes Stimulus Response Duration Importance
1. Moro Reflex Tested on a padded
surface e.g. on crib
cushion or foam mat.
Child is held at a 45
degree angle to the
supporting surface. The
head is then lifted up
slightly. Allow the head to
suddenly fall a couple of
centimeters before
immediately supporting
the head again (don’t
allow head to make
contact with the padded
surface though). Also by
change in movement or
position or temperature.
Arms and legs extend
and abducted suddenly
with spreading of the
fingers followed by
adduction and flexion
as the arms return to
the normal position.
Appears in utero and
disappears 6 months
postpartum.
- Moro reflex precedes the startle reflex
- May signify CNS dysfunction if lacking
or persists. Over exaggerated or
persistent in case of some neurological
conditions e.g. CP decreased or
absent in hypertonia due to
neuromuscular defects. Also absent if
neonate with septicemia, hypoxia.
- Persistence causes difficulty in
transitioning and poor balance in
positions like head control & sitting
where the child is uncertain about
own reactions and fearful of positional
change
- May indicate injury to one side of
brain if asymmetrical e.g. Erb’s palsy

10. Primitive Reflexes
Primitive Reflexes Stimulus Response Duration Importance
Startle Reflex Same as Moro.
Elicited by a rapid
change of head
position, by
striking the surface
that supports the
baby, or by a loud
noise (hitting the
exam table) like
tapping flexion of
the elbows and
adduction of the
fingers is flexion of
the elbows and
adduction of the
fingers is on the
sternum.
Arms and legs
flex. Abduction of
the arms with on
the sternum.
2-3 months
after Moro
disappears – 1
year
- Over exaggerated in case of
neurological injuries e.g. CP.
causing poor balance in
sitting
- Less severe startle reflexes
elicited through lifespan

11. Primitive Reflexes
Primitive Reflexes Stimulus Response Duration Importance
Asymmetric Tonic
Neck Reflex (ATNR)
Prone/supine position,
turn head to one side.
Elicited head is turned
to the side and kept
there for 15 seconds
(position of the head is
the eliciting stimulus)
Limbs flex on one
side, extend on other
side. This is called a
“fencing” position.
The arm and leg on
the side of the skull
remain in flexion,
whilst the arm and
the leg on the face
side extend.
Reflex is less
obvious during the
first month,
becoming more
obvious during
months 2-4 and
disappears by 3
months
- Facilitates bilateral body awareness
- Facilitates hand-eye coordination
- If the child does not revert to a
normal symmetrical position
within seconds this is to be
considered an abnormal reflex.
- If persistent (e.g. Neurological
injuries like C.P.)
- Difficulty in visual pursuits
(tracking) - Impaired
Symmetric Tonic Neck
Reflex (STNR)
- Baby sitting up and
tip forward
- Baby sitting up and
tip backward
- Neck and arms
flex, legs extend
- Neck and arms
extend, legs flex
After birth – 3
months
Persistence (e.g. neurological injuries like
C.P.) may impede many motor skills and
cause spinal flexion deformities

12. Primitive Reflexes
Primitive Reflexes Stimulus Response Duration Importance
Plantar Grasp Reflex Touching the ball of foot
by pressing on the sole of
the foot near the base of
the toes.
Toes grasp. The toes
and the ball of the
foot curl around the
finger
Birth – 1 year Must disappear before the baby can
stand or walk. Issue of shoes versus no
shoes?
Spinal Gallant Reflex Holding the baby in ventral
suspension. Pull your
finger down the lateral
side of the back muscles
unilaterally
The spine and torso
curve towards the
side where the
fingers are
20 weeks’
gestation and
should be inhibited
by 3-9 months
- Aids the birth process
- Absence of this reflex can be
valuable in determining sensory
loss in the case of neural tube
defects
- Persistence of this reflex can affect
the child’s ability to sit, poor
posture (scoliosis)

13. Primitive Reflexes versus Postural Reactions
Primitive Reflexes Postural Reactions
Present at birth Appear later
Disappear or integrate into
voluntary movements
Appear to persist
Originate from brainstem or
spinal cord
Originate from cerebral cortex
Essential for survival,
nutrition, protection and
development
Normal motor behavior

14. Postural Reactions
1. Stepping
2. Crawling
3. Swimming
4. Head – body righting
5. Parachuting
6. Labyrinthine
7. Pull up

15. Postural Reactions
Postural Reactions
Stimulus Response Duration Importance
1. Stepping Infant upright with feet
touching surface. Baby
held supported under
axilla’s with the soles of
the feet on a firm, flat
supporting surface
Legs lift and descend.
The baby
automatically steps
one foot in front of
the other
After birth – 5-6
months
Essential fore-runner to walking.
Sometimes called walking reflex. In
children with CP can still observe this
reflex when holding the child up, do not
confuse with voluntary gait
2. Crawling Prone position on surface,
stroke alternate feet
Legs and arms move in
crawling action
Birth 3-4 months Believed to be essential to the voluntary
creeping movement
3. Swimming Infant held horizontally Arms and legs move in
coordinated swimming
type action
2 weeks after birth – 5
months
Recognition of reflex led to popularity of infant
swim programs

16. Postural Reactions
Postural Reactions
Stimulus Response Duration Importance
4. Head and Body
Righting
Supine, turn body in either
direction
Head “rights” itself with
the body when the body
is turned to one side.
Then, the body follows
head
Head: 1-6 months;
Body: 5 months-1 year
Precursor to rolling movements
5. Parachuting Off balance in upright
position. Holding the baby
in ventral suspension with
the head down
Protective movement in
direction of fall.
Extension of the arms
should occur to protect
the head
4 months – 1 year
(never disappears)
- Assessed in preterm babies as markers
of neurological development. Related to
upright posture
- Also called propping reflex
- A conscious attempt to break a potential
fall
- Occurs downward, sideways, &
backward
6. Labyrinthine Baby held upright, tilted in
one direction
Baby tilts head in
opposite direction. Head
tilts in the opposite
direction of body tilt.
2-3 months – 1 year - Related to upright posture
- Also considered primitive reflex

17. Postural Reactions
Postural Reactions
Stimulus Response Duration Importance
7. Pull Up Sitting/standing, hold
hands, tip in one direction
Arms flex or extend in to
maintain upright position
3 months – 1 year Related to upright posture

18. •THANK YOU

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