 Another strand of investigation in this area is whether the presence of delusions signals a failure of self knowledge. There are several apparent manifestations of poor knowledge of the self in delusions (see Kircher and David 2003; Amador and David 1998). When we are attributed delusions of passivity, we may not recognize a movement as our own, and thus have a distorted sense of our personal boundaries; in thought insertion, we come to believe that there is a thought in our head that has been placed there by a third party (e.g., Stephens and Graham 2000). Sometimes we act or feel in a way that is incompatible with the content of our delusions, or are unable to endorse the content of our delusion with reasons that are regarded by others as good reasons (e.g., Gallagher 2009; Bortolotti and Broome 2008, 2009; Fernández 2010). Finally, the presence of delusions may make it difficult for us to remember our experienced past accurately and to plan for the future, because we are unreliable autobiographers (e.g., Gerrans 2009, 2014).