NEONATAL REFLEXES PRIMARY MOTOR PATTERNS INFANT REFLEXES & REACTIONS

Neonatal Reflexes or Primary Motor Patterns and Infant Reflexes & reactions In neonates & infants, motor behavior influenced by primitive reflexes as a result of immature CNS during first 6-8 months of life as CNS matures, reflexes gradually suppressed Reflexes generate predictable & stereotypic movements and postures. Present at birth and become “integrated” or inhibited, or not evident later in development In CNS lesions, may persist and interfere with motor milestone attainment, or cause deformities

Neonatal Reflexes or Primary Motor Patterns and Infant Reflexes & reactions Reflexes form the basic organized pathways in the spinal cord and regulation from the higher centers is accomplished by excitation and inhibition of these reflexes Spinal and brainstem level reflexes have to be inhibited Midbrain and cortical reflexes must be encouraged

Level Classification of Reflexes Spinal Reflexes Flexor withdrawal Extensor thrust Crossed extension Moro Startle Brainstem Reflexes Tonic neck reflexes - ATNR - STNR 2) Static labyrinthine 3) Positive supporting 4) Negative supporting

Level Classification of Reflexes Midbrain Reflexes Kinetic Labyrinthine Superior semi-circular canal Posterior semi-circular canal Body righting acting on head Body righting acting on body Optical righting reflex Labyrinthine righting reflex Amphibian reflex Protective extension Parachute reflex Brainstem Reflexes Equilibrium reflexes - Side tilting - Forward tilting - backward tilting

Level Classification of Reflexes Reflexes without Classification Sucking reflex Grasp reflex Placement reflex Stepping reflex Standing reflex

Reflex Development (ref: Molnar, ch. 2 Growth & Development ) STIMULUS RESPONSE AGE OF SUPPRESSION Moro Sudden neck extension Shoulder abduction; shoulder, elbow & finger extension followed by arm flexion abduction 4-6 months Startle Sudden noise, clapping Same as Moro Rooting Stroking lips or around mouth Moving mouth, head toward stimulus, in search of nipple 4 months Positive supporting Light pressure or weight bearing on plantar surface Legs extend for partial support of body weight 3-5 months Replaced by volitional weight bearing w support Asymmetric Tonic Neck Head turning to side Extremities extend on face side, flex on occiput side 6-7 months Symmetric Tonic Neck flexion Neck extension Arms flex, legs extend Arms extend, legs flex

Reflex Development (Molnar) STIMULUS RESPONSE AGE OF SUPPRE Palmar grasp Touch or pressure on palm or stretching finger flexors Flexion of all fingers, hand fisting 5-6 months Plantar grasp Pressure on sole distal to metatarsal heads Flexion of all toes 12-14 months when walking is achieved Automatic neonatal walking On vertical support, plantar contact & passive tilting of body forward & side to side Alternating automatic steps with support 3-4 months Placement or placing Tactile contact on dorsum of foot/hand Extremity flexion to place hand or foot over an obstacle Before end of 1st year Neck righting or body derotational Neck rotation in supine Sequential body rotation from shoulder to pelvis towards direction of face 4 months. Replaced by volitional rolling Tonic labyrinthine Head position in space, strongest at 45* from horizontal: Supine: extensor tone Prone : flexor tone 4-6 months

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRESSION Babinski Stroke lateral aspect of the plantar surface of foot Extension & fanning of toes 0-12 months Flexor withdrawal Sharp, quick pressure stimulus to the sole of the foot or palm of hand Withdrawal of stimulated extremity 0-2 months Present throughout life? Crossed extension Sharp, quick pressure stimulus to sole of foot Withdrawal of stimulated lower extremity & extension of opposite leg Galant or trunk incurvation reaction Sharp stroke along paravertebral line from scapula to top of iliac crest Lateral trunk flexion towards stimulated side Primary standing reaction Hold infant in supported standing Infant supports some weight & extends lower extremities If persists, interferes w walking by cause extension of all joints

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRE Primary walking Hold infant in supported standing, tilt trunk forward slightly Reciprocal Extension & fanning of toes 0-2 months Neonatal neck righting (Neck rightng on body, NOB Turn head when infant is in supine Body logrolls toward same side 0-6 months Rooting Stroking of perioral region Head turning to that side with mouth opening 0-3 months Impt feeding reflex Sucking Touch to lips, tongue, palate Results to automatic sucking Palmar grasp Pressure stimulus against palm Grasping of object with slow release 0-4 months Plantar grasp Pressure stimulus to sole or lowering feet to floor Curling of toes 0-9 months

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRE Tonic labyrinthine reflex Prone position Supine position Maximal flexor tone Maximal extensor tone 0-6 months If reflex persist, block rolling from supine due to increased extensor tone Asymmetric tonic neck reflex Rotation of head Extension of face side extremities & flexion of skull side extremities 0-5 months. *If persists, results in scoliosis/hip dislocation; interferes w grasping & hand to mouth activities Placing reactions Drag dorsum of foot or back of hand against edge of table Placing of foot or hand onto to table top Traction or pull-to-sit Pull infant to sit from supine Upper extremities will flex & there will be head lag Until about 4-5 months Optical & labyrinthine righting Body is tilted Head orients to vertical position 1 month-throughout life

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRE Protective extension Quick displacement of trunk in downward direction while held or while sitting in forward, sideward or backward direction Extension of legs in downward & extension of arms in the sitting position to catch weight Downward begins 4 mo Sideward sitting 6 mos Forward sitting 7 mos Backward sitting 9 mos These reactions persist through life Body-righting reaction acting on the head (BOH) Contact of the body with a solid surface Head righting with respect to gravity Interacts with labyrinthine-righting reaction on head to maintain orientation of head in space Begins at 4-6 months & persists throughout life Body-righting acting on the body (BOB) Rotation of head or thorax Rolling over with rotation between trunk & pelvis Begins at 6-8 months and persists

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRE Symmetrical tonic neck reflex Extension of cervical spine joints Flexion of cervical joints Extension of upper extremities & flexion of lower extremities Flexion of upper extremities & extension of lower extremities 6-8 months If reflex persist, may interfere w development of stable quadruped position & creeping Landau’s reaction Infant held in ventral suspension Extension of neck, trunk & hips 4-18 months Tilting reactions Slow shifting of base of support or slow displacement of body in space Lateral flexion of spine toward elevated side of support, abduction of extremities on elevated side; sometimes trunk rotation toward elevated side Prone begins @ 5 mos Supine begins @ 7 mos Sitting @ 8 mos Quadruped @ 12 mos These reactions persist throughout life

Reflex Development (ref: O’Sullivan and Siegelman ) STIMULUS RESPONSE AGE OF SUPPRESSION Moro reflex Sudden extension of the neck Flexion, abduction of shoulders, extension of elbows  extension, abduction of shoulders, flexion of elbows Usually also results in crying Test last! 0-4 months Startle

Plantar Response: Babinski Reflex