Moreover, it is the distinct developmental brain abnormality in "microcephalic osteodysplastic primordial dwarfism" (MOPD1). One of "Freaks" main characters is a microcephalic, or "pinhead," named Schlitzie. His unusual appearance caused many to believe that he was a "pinhead", or microcephalic. Additionally, he possibly did not suffer the mental retardation that microcephalic people often suffer. In some sideshows, he was paired with another microcephalic performer. Children often present with developmental delay, spasticity, or seizures; they are also often microcephalic. Jacob insisted that the remains were those of microcephalic modern humans.