My cousin is suffering with this problem.if i ask anything for 4 times then for the last time she will answer it.she is laughing without any reason.and even speaking with some one who is not there.always thinking about something.doing small work for long time.she is always saying that somebody is speaking with her and somebody is following her.but i couldnt see anyone.while speaking she suddenly stops speaking and laughing or just keeping quiet.if i ask her what happened for two or more times,she says nothing.