Mental shield

Mental Shield is the ability to block out all mental attacks such as;
 * Edward's telepathy
 * Jane's illusion of pain
 * Zafrina's visual projection
 * Kate's electrical current
 * Alec's sensory paralysis
 * Renata's protective shield
 * Aro's tactile telepathy
 * Demetri's tracking sense
 * Eleazar's ability identification
 * Chelsea's relationship manipulation

==Bella Swan==

Bella Swan is the only known person with this ability and considered it a 'glitch' in her head whilst she was still human. It also made Bella very desirable to Aro, who looks to collect vampires with special abillities for the Volturi guard.

Once she is turned into a vampire though it is identified as an ability by Eleazar, who has the gift of identifying others abilities.

With the help of Kate and Zafrina, Bella learns to control and use her shield, eventually shielding more than one person at once. This came in useful in Breaking Dawn when she domes her shield to protect her family and friends, meaning they could not be attacked by Jane or Alec, or any of the Volturi guard. Bella also learns to lower her shield to allow mental abilities to work on her, such as Edward reading her mind at the end of Breaking Dawn.

The only person to penetrate this shield is Renesmee, who can place images and thoughts inside Bella's mind through a single touch. This is because she has the exact opposite abilities of her parents.

In Eclipse, it is explained why Alice and Jasper's abilities are thought to be able to work on Bella when all other vampires abilities so far have proved ineffective at arrecting her. Alice explained that her ability to see the future is only seeing outcomes caused by decisions not the thoughts behind those decisions. Jasper's ability is said to work on Bella because his ability actually changes one's mood and does not just create a mental illusion such as Jane's ablility to create the illusion that you are in extreme amounts of pain. Many people believe this argument makes no sense, believing that she actually sees the decisions. However Alice does not see the decision but only the path that is created once one has been made.