Gifted humans

Throughout the Twilight Saga there have gifted humans have made numerous appearances. One of the most prominent character that has such abilities is Bella Swan over the course of Twilight, New Moon and Eclipse no one has been to psychically affect Bella because of her raw natural ability to create a psychic shield made to repel all mind related powers. it has also been indicated that Alice Cullen was a gifted human before becoming a vampire. Alice was incarcerated in a asylum for mentally ill because she had precognitive visions of the future. Also mentioned is Benjamin, Jane and Alec it was hinted throughout the books that they were gifted humans before their transformation. Amun changed Benjamin knowing he would have tremendous abilities, although it can also mean Amun has similar powers to Eleazar (identifying special abilities) but the possibility is improbable. Aro also knew of Jane and Alec's abilities before they became vampires to a point where he wanted to wait until they were mature enough to join the Volturi but before they could grow into adults Alec and Jane were condemned to be burnt at the stake, making Aro turn them into vampires much earlier then expected.It is also pointed out in the book that Vampires find gifted humans much more appetizing then normal humans. Edward found Bella's blood to be the most potent and appetizing blood there is, just as when James said that Alice smelled better then her when she was human, ( this meaning, the more powerful the ability the more potent and appetizing the person's blood will be).