Which primitive reflex typically lasts until around 1 year of age?

Which primitive reflex typically lasts until around 1 year of age?

• A. Moro
• B. Rooting
• C. Babinski
• D. Sucking

Answer: (C)

The main idea here is how primitive reflexes fuse as the nervous system matures. The Babinski (plantar) reflex is present at birth and tends to persist longer than the others because it reflects immature corticospinal pathways. When you stroke the sole, the infant’s big toe dorsiflexes and the other toes fan out. As myelination and cortical control develop, this response fades, usually by about 12 to 24 months, so it’s often seen as lasting roughly until around one year. In contrast, the Moro reflex is a startle pattern that typically disappears by 4–6 months, and the rooting reflex (turning toward a touch on the cheek) disappears around 4 months as feeding becomes more voluntary. The sucking reflex also helps early feeding but becomes integrated as voluntary sucking patterns emerge; it does not persist as long as the Babinski sign.

The main idea here is how primitive reflexes fuse as the nervous system matures. The Babinski (plantar) reflex is present at birth and tends to persist longer than the others because it reflects immature corticospinal pathways. When you stroke the sole, the infant’s big toe dorsiflexes and the other toes fan out. As myelination and cortical control develop, this response fades, usually by about 12 to 24 months, so it’s often seen as lasting roughly until around one year. In contrast, the Moro reflex is a startle pattern that typically disappears by 4–6 months, and the rooting reflex (turning toward a touch on the cheek) disappears around 4 months as feeding becomes more voluntary. The sucking reflex also helps early feeding but becomes integrated as voluntary sucking patterns emerge; it does not persist as long as the Babinski sign.