The document discusses various reflexes seen in infants and their significance. It begins by defining a reflex and describing the basic reflex arc involving receptors, afferent nerves, centers, efferent nerves and effectors. Reflexes are then classified based on whether they are inborn or acquired, their neurological pathway, purpose and clinical presentation. Several important reflexes seen in newborns like the moro, rooting and babinski reflexes are explained in detail. The document emphasizes that assessment of infant reflexes helps identify normal development and potential abnormalities.

1. Presented by:
Piyush Verma
MDS 2nd yr
Dept of Paedodontics & Preventive Dentistry

2. Contents
 Introduction
 Reflex arc
 Classification of reflexes
 Significance of reflexes
 Types of reflexes
 Conclusion

3. Introduction
 A reflex is an involuntary or automatic action that your
body does in response to something without even
having to think about it
 Neonatal reflexes – inborn reflexes present at birth &
occur in a predictable fashion
 Normally developing newborn should respond to
certain stimuli with these reflexes

4. Reflex arc
 Anatomical pathway for a reflex is
called as reflex arc
 It has 5 components :
 Receptor
 Afferent nerve
 Center
 Efferent nerve
 Effector organ

5. Classification of reflexes
 Depending upon whether inborn or acquired
 Unconditioned reflexes, inborn reflex
 Conditioned reflexes/acquired reflexes

6.  Depending upon the situation of the center
 Cerebellar reflexes
 Cortical reflex
 Midbrain reflex
 Bulbar or medullary reflexes
 Spinal reflexes

7.  Depending upon the purpose
 Protective/flexor reflexes
 Antigravity/extensor reflexes
 Depending upon clinical basis
 Superficial reflexes
 Mucus membrane
 Cutaneous reflex
 Deep reflexes
 Visceral reflexes
 Pathological reflexes

8. Significance of reflexes
 Helps a paedodontist to identify whether the child is
developing normally or not
 Tells about what abnormalities the child may be
having if all reflexes are not proper
 Knowledge of development of motor skills – helps to
identify whether development is going on at a proper
rate or not

9. Types of reflexes

10. General body reflexes :
 Moro reflex/Startle reflex
 Palmar/grasp reflex
 Plantar grasp reflex
 Walking/stepping reflex
 Limb placement reflex
 Asymmetric tonic neck reflex
 Symmetric tonic neck reflex
 Babinski’s reflex
 Babkin reflex
 Parachute reflex
 Landau reflex

11.  Withdrawal reflex
 Trunk incurvation reflex
 Tendon reflexes
 Gallant’s reflex
Tonic labyrinthine reflex
Facial reflexes :
 Nasal reflex
 Blink reflex
 Doll’s eye reflex
 Auditory orienting reflex

12. Oral reflexes :
 Rooting reflex
 Sucking reflex
 Swallowing reflex
 Gag reflex
 Cry reflex

13. General body reflexes
 Moro reflex/ startle reflex
 Begins at 28 weeks of gestation
 Initiated by any sudden movement of
the neck
 Elicited by -- pulling the baby halfway
to sitting position from supine &
suddenly let the head fall back
 Consists of rapid abduction & extension
of arms with the opening of hands,
tensing of the back muscles, flexion of
the legs and crying

14. Within moments, the arms come together again
 Clinical significance
Its nature gives an indication of muscle tone
Failure of the arms to move freely or the hands to open
fully indicates hypotonia.
It fades rapidly and is not normally elicited after 6
months of age.

15.  Palmar/grasp reflex
 Begins at 32 weeks of gestation
 Light touch of the palm produces
reflex flexion of the fingers
 Most effective way -- slide the
stimulating object, such as a finger
or pencil, across the palm from the
lateral border
 Disappears at 3-4 months
 Replaced by voluntary grasp at 45
months

16.  Clinical significance
 Exceptionally strong grasp reflex -- spastic form of cerebral
palsy & Kernicterus
 May be asymmetrical in hemiplagia & in cases of cerebral
damage
 Persistence beyond 3-4 months indicate spastic form of
palsy

17.  Plantar/grasp reflex
 Placing object or finger beneath the
toes causes curling of toes around the
object
 Present at 32 weeks of gestation
 Disappears at 9-12 months
• Clinical significance :
 This reflex is referred to as the
"readiness tester".
 Integrates at the same time that
independent gait first becomes
possible.

18.  Walking/stepping
reflex
 When sole of foot is pressed
against the couch, baby tries to
walk
 Legs prance up & down as if baby
is walking or dancing
 Present at birth, disappears at
approx 2-4 months
 With daily practice of reflex,
infants may walk alone at 10
months

19. Clinical significance
Premature infants will tend to walk in a toe-heel
fashion while more mature infants will walk in a
heel-toe pattern.

20.  Limb placement reflex
 When the front of the leg below the
knee or the arm below the elbow is
brought into contact with the edge
of a table, child lifts the limbs over
the edge
 Present at birth, fades away rapidly
in early months of life
• Clinical significance
 Reflex is readily demonstrable in the
newborn and persistent failure to
elicit it at this stage, is thought to
indicate neurological abnormality

21.  Withdrawal reflex
 Protective reflex
 Stimulus : a pinprick or a sharp
painful stimulus to sole of foot
 Response : flexion & withdrawal of
stimulated leg
 Present at birth, persists throughout
life
 Clinical significance – Absence of
this is seen in neurologically impaired
infants.

22.  Asymmetric tonic neck reflex
 Most evident between 2-3 months of age
• Clinical significance
 The reflex fades rapidly and is not normally
seen after 6 months of age.
 Persistence is the most frequently observed
abnormality of the infantile reflexes in
infants with neurological lesions
 Greatly disrupts development

23.  Symmetric tonic neck
reflex
 Extension of the head causes
extension of the fore limbs and
flexion of the hind limbs
Evident between 2-3 months of age
 Clinical significance
 Not normally easily seen or elicited in
normal infants
 May be seen in an exaggerated form
in many children with cerebral palsy.

24.  Babinski’s reflex
 Stimulus consists of a firm painful stroke
along the lateral border of the sole from heel
to toe
 Response consists of movement (flexion or
extension) of the big toe and sometimes
movement (fanning) of the other toes
 Present at birth, disappears at approx 9-10
months
 Presence of reflex later may indicate disease

25.  Babkin reflex
 Deep pressure applied simultaneously
to the palms of both hands while the
infant is in supine position
 Stimulus is followed by flexion or
forward bowing of the head, opening of
the mouth and closing of the eyes
 Fades rapidly and normally cannot be
elicited after 4 months of age.

26. • Clinical significance
 Reflex can be demonstrated in the newborn, thus showing
a hand-mouth neurological link, even at that early stage

27.  Parachute reflex
 Reflex appears at about 6-9 months &
persists thereafter
 Elicited by holding the child in ventral
suspension & suddenly lowering him to the
couch
 Arms extend as a defensive reaction
• Clinical significance
 Absent or abnormal in children with
cerebral palsy
 Would be asymmetrical in spastic
hemiplagia

28.  Landau reflex
 Seen in horizontal suspension with the
head, legs & spine extended
 If the head is flexed, hip knees &
elbows also flex
 Appears at approximately 3 months,
disappears at 12-24 months
• Clinical significance
 Absence of reflex occurs in hypotonia,
hypertonia or mental abnormality

29.  Trunk incurvation reflex
 Stroking one side of spinal column
while baby is on his abdomen causes
 Crawling motion with legs
 Lifting head from surface
 Present in utero, seen at
approximately 3rd or 4th day
 Persists for 2-3 months

30.  Gallant’s reflex
 Firm sharp stimulation along sides of
the spine with the fingernails or a pin
produces contraction of the underlying
muscles and curving of the back.
 Response is easily seen when the infant
is held upright and the trunk
movement is unrestricted
 Best seen in the neonatal period and
thereafter gradually fades.

31.  Tendon reflexes
 Simple monosynaptic reflexes, which are elicited by a
sudden stretch of a muscle tendon
Occurs when the tendon is tapped
Present throughout life

32. Spinal cord levels of the tendon reflexes

33.  Clinical significance
 Useful diagnostically for :
Detection of upper motor neuron lesions (exaggerated
response)
Myopathic conditions (depressed or absent response)
Localization of the segmental lesions of the cord.

34.  Tonic labyrinthine reflex
 Labyrinths -- most important organs
concerned with the development of
anti-gravity postures and balance
 Movement of the head in any
dimension stimulates the labyrinths;
and produces the appropriate
responses
 Arms & legs extend when head moves
backwards, & will curl in when the
head moves forward
 Emerges in utero until approximately
4 months postnatally

35. Facial reflexes
 Nasal reflex
 Stimulation of the face or nasal cavity with water or local
irritants produces apnea in neonates
 Breathing stops in expiration with laryngeal closure in
infants – bradycardia & lowering of cardiac output
 Blood flow to skin, splanchnic areas muscles & kidney
decreases
 Flow to the heart & brain remains protected

36.  Blink reflex
 A bright light suddenly shone into the eyes, a puff of air
upon the sensitive cornea or a sudden loud noise will
produce immediate blinking of the eyes
 Purpose – to protect the eyes from foreign bodies & bright
light
 May be associated tensing of the neck muscles, turning of
the head away from the stimulus, frowning and crying
 Reflexes are easily seen in the neonate and continue to be
present throughout life

37.  Clinical significance
 Examination is a part of some neurological exams,
particularly when evaluating coma
Satisfactory demonstration of these reflexes indicate –
 No cerebral depression
 Contraction of appropriate muscles in response

38.  Doll’s eye reflex
(Oculocephalic reflex)
 Passive turning of the head of
the newborn leaves the eye
“behind”
 A distinct time lag occurs before
the eyes move to a new position
in keeping with the head position
 Disappears at within a week or
two of birth
 Failure of this reflex to appear
indicates a cerebral lesion
Head
Eye

39.  Auditory orienting reflex
 A sudden loud and unpleasant noise :
 May produce the blink reflex
 Infant may remain still and show increased alertness
 Quieter sounds usually cause reflex eye and head turning to the
side of the sound, as if to locate it
 Seen first at about 4 months of age
 Thereafter, head turning towards sound stimuli occurs and the
accuracy of localization increases rapidly by 9-10 months

40.  Clinical significance
 Reflex responses are made use of in tests of infants for
hearing loss
 Pattern of the localization responses indicates the level of
neurological maturity

41. Oral reflexes
 Rooting reflex
 Baby’s cheek is stroked :
 They respond by turning their head
towards the stimulus
 They start sucking, thus allowing for
breast feeding
 When corner of mouth is touched, lower
lip is lowered, tongue moves towards the
point stimulated
 When finger slides away, head turns to
follow it
 When center of lip is stimulated, lip
elevates

42.  Onset -- 28 weeks IU
 Well established – 32-34 weeks IU
 Disappears – 3-4 months
 Clinical significance
Persistence can interfere with sucking
 Absence of this is seen in neurologically impaired
infants.

43.  Sucking / Swallowing
reflex
 Touching lips or placing something in
baby’s mouth causes baby to draw
liquid into mouth by creating vacuum
with lips, cheeks & tongue
 Onset – 28 weeks IU
 Well established – 32-34weeks IU
 Disappears around 12 months

44. Clinical significance :
Persistence may inhibit voluntary sucking
Sigmund Freud - Any kind of deprivation of the
activity will lead to fixation resulting in oral habits

45.  Gag reflex
(Pharyngeal reflex)
 Seen in 19 weeks of IU life
 Reflex contraction of the back
of the throat
 Evoked by touching the roof of
the mouth, the back of the
tongue, the area around the
tonsils and the back of the
throat

46.  Functional significance
 It, along with reflexive pharyngeal swallowing, prevents
something from entering the throat except as part of
normal swallowing and helps prevent choking
 Clinical significance
 Absence of the gag reflex -- symptom of a number of
severe medical conditions :
 Damage to the glossopharyngeal nerve, the vagus nerve,
 Brain death.

47.  Cry reflex
 Non conditioned reflex which
accounts for its lack of its
individual character
 Sporadic in nature
 Starts as early as 21-29 weeks of IU
life

48.  Importance of cry
 It is infant’s first verbal communication
 Can be interpreted as a message of urgency or distress
 Indicates:
 Hunger
 Pain
 Discomfort

49. Conclusion
Appropriate knowledge of reflexes enables a paedodontist
 to identify whether the child is developing normally or
not
 to identify whether development is going on at a proper
rate or not
 Knowledge of abnormalities if all reflexes are not proper

51. References
 Shobha Tandon. Textbook of Paedodontics
 MS Muthu. Paediatric Dentistry, Principals & practice