Infant Reflexes

role of reflexes in survival

- Infant reflexes are called primitive reflexes - Primitive reflexes are repressed by 6 months of age - Primitive reflexes are important for: + Protection + Nutrition + Survival

Galant Reflex

https://www.youtube.com/watch?v=-vBZesEaYYs

Landau Reflex

https://www.youtube.com/watch?v=jEDixMrg1nw

normal newborn reflexes

- Root - Suck - Morro - Tonic Neck (ATNR) - Grasp - Babinski - Step

symmetric tonic neck reflex (STNR)

- Limbs respond symmetrically - Its persistence may impede other motor milestones - Place baby in a sitting position ~ tip forward + Neck flexes Arms flex Legs extend - Place baby in a sitting position + Tip backward Neck extends Arms extend Legs flex

startle reflex

- May not appear until 2-3 months after Moro disappears - Elicited by a rapid change of head position, by striking the surface that supports the baby, loud noise - Causes the arms and legs to flex immediately

role of reflexes in developing future movement: postural reflexes

- Prevalent belief: automatic movement is "practice" for future voluntary movement - Other experts believe these reflexes may not be related to future motor development - Emanate from higher brain centers - Reflexes disappear when voluntary behavior surfaces - When the stepping reflex is stimulated, walking may begin at an earlier age - Link between stimulation of the reflex preceding the disappearance phase and early movement - Small amounts of practice can lead to significant results

postural reflexes: parachuting reflexes

- Propping reflexes - Related to upright posture - This reflex is a conscious attempt to break a potential fall

what are reflexes?

- Reflexes are involuntary movements or actions. - Some movements are spontaneous, occurring as part of the baby's usual activity. - Others are responses to certain actions. - Health care providers check reflexes to determine if the brain and nervous system are working well. - Some reflexes occur only in specific periods of development.

what are reflexes? continued...

- Reflexive movements occur during the last 4 months of prenatal life and the first 4 months after birth - Reflexes occur subcortically (below the level of the higher brain centers) - Most "infant" reflexes do not last beyond the first year - Reflexes that endure are called "lifespan" reflexes + Knee-jerk reflex + Flexor-withdrawal reflex - Many of the reflexes do not completely disappear + First, they are inhibited by the maturing nervous system + Second, they are integrated into new movement behaviors

suck reflex

- Rooting helps the baby become ready to suck. - When the roof of the baby's mouth is touched, the baby will begin to suck. - Occurs both pre and postnatally - Begin until about the 32nd week of pregnancy and is not fully developed until about 36 weeks. - Premature babies may have a weak or immature sucking ability because of this. - Babies also have a hand-to-mouth reflex that goes with rooting and sucking and may suck on fingers or hands.

moro reflex

- The Moro reflex is often called a startle reflex because it usually occurs when a baby is startled by a loud sound or movement. - In response to the sound, the baby throws back his or her head, extends out the arms and legs, cries, then pulls the arms and legs back in. - A baby's own cry can startle him or her and trigger this reflex. - Testing Moro Reflex - + Palm of hand lifts back of head + Hand is removed suddenly so that head begins to fall - Head is supported - Moro reflex precedes the startle reflex and causes the arms and legs to extend immediately rather than flex - Moro reflex - May signify a cerebral birth injury if lacking or asymmetrical - This reflex lasts until the baby is about 4 to 6 months old

postural reflexes: head and body righting

- The head "rights" itself with the body when the body is turned to one side - Body follows head - Precursor to rolling movements - Body righting may not be evident before month 5

palmar grasp reflex

- The palmar grasp reflex is one of the most noticeable reflexes to emerge - Appears in utero - Stroking the palm of a baby's hand causes the baby to close his or her fingers in a grasp. - Negative palmer grasp: neurological problems; spasticity - Leads to voluntary reaching and grasping - The grasp reflex lasts until the baby is about 5 to 6 months old.

plantar reflex

- The toes appear to be grasping - Stimulus is touching the ball of the foot - This reflex must disappear before the baby can stand or walk

root reflex

- This reflex begins when the corner of the baby's mouth is stroked or touched. - The baby will turn his or her head and open his or her mouth to follow and "root" in the direction of the stroking. - This helps the baby find the breast or bottle to begin feeding. - Usually works in conjunctions with sucking reflex - Contributes to head- and body-righting reflexes - This reflex lasts about 4 months.

postural reflexes: Labyrinthine reflex

- This reflex endures throughout most of the first year - Related to upright posture - Head tilts in the opposite direction of body tilt

step reflex

- This reflex is also called the walking or dance reflex because a baby appears to take steps or dance when held upright with his or her feet touching a solid surface. - This reflex lasts about 2 months.

asymetrical tonic neck reflex (ATNR)

- When a baby's head is turned to one side, the arm on that side stretches out and the opposite arm bends up at the elbow. - This is often called the "fencing" or "archer" position. - Causes flexion on one side and extension on the other - Not always seen in newborn - Thought to facilitate the development of bilateral body awareness - Persistent asymmetric tonic neck reflex - May indicate cerebral palsy or other neurological problem - This reflex lasts until the baby is about 5 to 6 months old.

Babinski's reflex

- When the sole of the foot is firmly stroked, the big toe bends back toward the top of the foot and the other toes fan out. - Elicited by a stimulus similar to plantar grasp, but response is different - Test of the pyramidal tract activity for later motor movement - This normal reflex lasts until the child is about 2 years of age.

postural reflexes: pull-up reflex

When the baby is tipped backward, supporting arms flex in an effort to maintain the upright position