Lissencephaly means “smooth brain.” The normal folds are missing or very shallow, so the surface looks almost flat. This rare change is usually spotted before birth or soon after delivery. Head size may be smaller than expected at birth, but some babies start with a normal head that grows slowly, slipping down the growth chart by three to six months. Muscle tone is often low at first. Infants feel floppy when lifted, and feeding can be weak, leading to long, sleepy feeds and slow weight gain. Seizures commonly start in the first weeks of life. They may look like brief... Learn more