 One issue with a majority of current research is that it occurs over a short time span such as a few hours to a couple of days; however, teachers and professors are more interested in ensuring the material they teach remains long term.Through the study of people's recollection of high school Spanish words, Harry Bahrick was able to show that a considerable portion of information learned in a particular class is remembered throughout a person's life and is known as permastore.Bahrick found that spaced post-study sessions promoted permastore for Spanish vocabulary, and likewise, Landauer and Ainslie found that the testing effect increased scores on the information over a year later.