lissencephaly

birth defect

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July 20, 2026

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Lissencephaly, meaning "smooth brain," is a birth defect characterized by an abnormally smooth cerebral cortex with few or no folds. This condition arises from disruptions in neuron migration during embryonic development, potentially due to genetic mutations, fetal infections, or insufficient blood supply to the developing brain.12

Infants with lissencephaly often exhibit microcephaly (reduced head size), muscle spasms, seizures, and developmental delays. While some affected infants can survive into childhood with intensive care, many do not live past age 10. Lissencephaly is one of several cephalic disorders that affect brain development.2

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cephalic disorder
Lissencephaly
Lissencephaly means “smooth brain.” The normal brain surface has many folds and grooves (gyri and sulci), but a brain affected by lissencephaly does not; the folds may be incomplete or entirely absent. Lissencephaly is further characterized by microcephaly (reduced head size) and by symptoms…
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Lissencephaly means “smooth brain.” The normal brain surface has many folds and grooves (gyri and sulci), but a brain affected by lissencephaly does not; the folds may be incomplete or entirely absent. Lissencephaly is further characterized by microcephaly (reduced head size) and by symptoms…
Read More