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Discussion Starter · #1 ·
why is it normal to have babinski sign in child but in adult its pathology?

kaplan- because in child neuron not myelinated

mechanism and relation?:notsure:
 

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I found this:

Infants will also show an extensor response. A baby's smaller toes will fan out and their big toe will dorsiflex slowly. This happens because the corticospinal pathways that run from the brain down the spinal cord are not fully myelinated at this age, so the reflex is not inhibited by the cerebral cortex. The extensor response disappears and gives way to the flexor response around 12-24 months of age.
 

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Discussion Starter · #5 ·
I found this:

Infants will also show an extensor response. A baby's smaller toes will fan out and their big toe will dorsiflex slowly. This happens because the corticospinal pathways that run from the brain down the spinal cord are not fully myelinated at this age, so the reflex is not inhibited by the cerebral cortex. The extensor response disappears and gives way to the flexor response around 12-24 months of age.
So the reflex is not inhibited by corticospinal pathway (by stretch reflex I guess)
Is it due to slow conduction!
but even though this tract is responsible for voluntary movement.
then again how? :toosad::toosad:
 

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So the reflex is not inhibited by corticospinal pathway (by stretch reflex I guess)
Is it due to slow conduction!
but even though this tract is responsible for voluntary movement.
then again how? :toosad::toosad:
im not so sure. but im pretty sure here its not about the slow conduction (although it is because of non complete myelination) but some other reason that has to do with the myelination. if someone else could fill us in on this one it'd be great to know y babinski is positive in infants up till 18 - 24 mths.
 

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guys in 1st aid it says it disappears @ 12- 14 months
lol.. yes u're rite. sorry. i should've said 12 to 18 months. that's the usual interval given. but 12 - 14 months is correct too. some books give a longer interval. however, if up till 2 yrs it is positive it shouldn't be considered abnormal until proven otherwise.:)
 
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