Example: I am fairly fast and accurate at typing. I am typing a study guide for my psychology class and am on the chapter about the nervous system. Every time I type the word system, I leave out the second ‘s’, regardless of how hard I try to type it correctly. I understand this example is trivial; however, having the same typing error on the same word got annoying and made me question the cause. So, What causes this type of “mental block” and is there a name for it? P.S. Please only respond if you have a serious, psychologically based answer.