"Cantor says his first indication that there was something different about pedophiles' brains was that, compared to teleiophile offenders (sex offenders who victimized adults), pedophiles' IQs were about 10 points lower on average. He also found that the age of a pedophile's victim was directly proportional to the pedophile's IQ—the younger the children, the lower the attacker's intelligence. "That was our first clue that the brain was somehow involved," says Cantor, adding that pedophiles also performed relatively poorly on memory tests. Other patterns soon emerged: Pedophiles tended to be shorter than teleiophiles, which Cantor says told him "whatever's going on, it's not just the brain; it seems to be that the whole body isn't formed quite correctly." Pedophiles were more likely to have failed grades in school. They were also more likely to have sustained head injuries before the age of 13. All of this helped lead Cantor to the suspicion that not only did pedophilia have to do with brain growth, it had to do with very early brain growth."