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IES Grant

Title: Optimizing Resistance to Forgetting
Center: NCER Year: 2004
Principal Investigator: Pashler, Harold E. Awardee: University of California, San Diego
Program: Cognition and Student Learning      [Program Details]
Award Period: 3 years Award Amount: $924,935
Goal: Exploration Award Number: R305H040108

The value of education depends not only on what is learned, but also on whether information, once learned, can be retained. Often the explanation for why students don't know something is not that they didn't learn it, but that they learned it and subsequently forgot it. The purpose of this project is to address the question of what instructional procedures foster long-term retention of information and skills, with a particular focus on factors that can be readily manipulated in almost every learning context, be it a classroom or a computer-aided instruction or distance-learning program.

The researchers in this project are adding a series of ten cognitive experiments to an ongoing research program examining factors that affect retention or forgetting of learned information. Two studies are designed to investigate the effects of different study schedules (i.e., different lengths of time between study sessions) on the retention of skills and knowledge, using vocabulary words taught to 8-10 year old children in one study, and people who visit an Internet site to learn about skin cancer detection in the other.

Two additional studies are designed to examine testing effects on fact and foreign language learning. Specifically, these studies will compare the effects of regular study activity (i.e., the simple presentation of information to be learned) versus using testing as a study method, and whether observed differences in learning vary depending upon the length of the retention interval.

Another study will compare discovery learning with learning under more passive conditions. Specifically, this study will examine whether children and adults who discover knowledge for themselves are more likely to learn and retain that knowledge than are individuals who receive the same knowledge more passively. In this study, participants will be randomly assigned to one of five different learning conditions varying in the extent to which they require active hypothesis testing to discover an underlying principle, versus being given the principle directly, and learning will be assessed following a 30-day retention interval.

Two studies will focus on whether receiving intermittent versus consistent performance feedback affect learning and retention of information, and two additional studies will assess the differential effects on learning and retention of six feedback conditions varying in how long feedback is delayed and how long it is available once presented.

The tenth study will examine the effectiveness of an intervention based on findings from the earlier studies, focusing on material that is already being taught to students enrolled in early high-school grades-particularly content that is taught once and that is not reviewed or practiced in other classes. Students will be randomly assigned to one of several review intervention conditions. The review session will take place at several possible delays after their classroom learning took place. Delay intervals and procedures for review will be developed based on earlier findings. After a delay of up to 18 months after the review session, a final test of retention will be given.

Finally, the researchers will use information obtained from these studies to develop a computer-based intervention designed to teach English vocabulary to learners such as high school students preparing for the SAT. Results from this work should provide new information relevant to classroom practice and instructional interventions designed to improve students' ability to retain learned information over extended periods of time.

Project Website:

Related Grants:
Optimizing Resistance to Forgetting (R305H020061)
Harnessing Retrieval Practice to Enhance Learning in Diverse Domains (R305B070537)
Interleaved Mathematics Practice (R305A110517)
An Efficacy Study of Interleaved Mathematics Practice (R305A160263)


Journal article, monograph, or newsletter

Carpenter, S., Pashler, H., and Cepeda, N.J. (2009). Using Tests to Enhance 8th Grade Students' Retention of U.S. History Facts. Applied Cognitive Psychology, 23(6): 760–771.

Carpenter, S., Pashler, H., and Vul, E. (2007). What Types of Learning are Enhanced by a Cued Recall Test?. Psychonomic Bulletin and Review, 13(5): 826–830.

Carpenter, S.K., and Pashler, H. (2007). Testing Beyond Words: Using Tests to Enhance Visuospatial Map Learning. Psychonomic Bulletin & Review, 14: 474–478.

Carpenter, S.K., Pashler, H., Wixted, J.T., and Vul, E. (2008). The Effects of Tests on Learning and Forgetting. Memory and Cognition, 36(2): 438–448.

Cepeda, N., Coburn, N., Rohrer, D., Wixted, J., Mozer, M., and Pashler, H. (2009). Optimizing Distributed Practice: Theoretical Analysis and Practical Implications. Experimental Psychology, 56(4): 236–246.

Cepeda, N., Vul, E., Rohrer, D., Wixted, J., and Pashler, H. (2008). Spacing Effects in Learning: A Temporal Ridgeline of Optimal Retention. Psychological Science, 19: 1095–1102.

Cepeda, N.J., Pashler, H., Vul, E., Wixted, J.T., and Rohrer, D. (2006). Distributed Practice in Verbal Recall Tasks: A Review and Quantitative Synthesis. Psychological Bulletin, 132(2): 354–380.

Jones, J., and Pashler, H. (2007). Is the Mind Inherently Forward Looking? Comparing Prediction and Retrodiction. Psychonomic Bulletin and Review, 14(2): 295–300.

Kang, S.H.K., Pashler, H., Cepeda, N.J., Rohrer, D., Carpenter, S.K., and Mozer, M.C. (2011). Does Incorrect Guessing Impair Fact Learning?. Journal of Educational Psychology, 103(1): 48–59.

Kang, S.K., McDaniel, M.A., and Pashler, H. (2011). Effects of Testing on Learning of Functions. Psychonomic Bulletin and Review, 18(5): 998–1005.

Mozer, M.C., Pashler, H., and Homaei, H. (2008). Optimal Predictions in Everyday Cognition: The Wisdom of Individuals or Crowds?. Cognitive Science, 32(7): 1133–1147.

Pashler, H., Rohrer, D., and Cepeda, N. J. (2006). Temporal Spacing and Learning. APS Observer, 19: 30–38.

Pashler, H., Rohrer, D., Cepeda, N.J., and Carpenter, S.K. (2007). Enhancing Learning and Retarding Forgetting: Choices and Consequences. Psychonomic Bulletin and Review, 14: 187–193.

Rickard, T., Lau, J., and Pashler, H. (2008). Spacing and the Transition From Calculation to Retrieval. Psychonomic Bulletin and Review, 15: 656–661.

Rohrer, D. (2009). The Effects of Spacing and Mixing Practice Problems. Journal for Research in Mathematics Education, 40(1): 4–17.

Rohrer, D. (2009). Avoidance of Overlearning Characterizes the Spacing Effect. European Journal of Cognitive Psychology, 21(7): 1001–1012.

Rohrer, D., and Pashler, H. (2007). Increasing Retention Without Increasing Study Time. Current Directions in Psychology Science, 16: 183–186.

Rohrer, D., and Taylor, K. (2006). The Effects of Overlearning and Distributed Practice on the Retention of Mathematics Knowledge. Applied Cognitive Psychology, 20(9): 1209–1224.

Rohrer, D., and Taylor, K. (2007). The Shuffling of Mathematics Problems Improves Learning. Instructional Science, 35(6): 481–498.

Rohrer, D., Taylor, K., Pashler, H., Wixted, J.T., and Cepeda, N.J. (2005). The Effect of Overlearning on Long-Term Retention. Applied Cognitive Psychology, 19(3): 361–374.

Taylor, K., and Rohrer, D. (2010). The Effects of Interleaved Practice. Applied Cognitive Psychology, 24(6): 837–848.

Vul, E., and Pashler, H. (2008). Measuring the Crowd Within: Probabilistic Representations Within Individuals. Psychological Science, 19(7): 645–647.

Vul, E., Harris, C., Winkielman, P., and Pashler, H. (2009). Puzzlingly High Correlations in fMRI Studies of Emotion, Personality, and Social Cognition. Perspectives on Psychological Science, 4(3): 274–290.


Carpenter, S.K., Pashler, H., Cepeda, N.J., and Alvarez, D. (2007). Applying the Principles of Testing and Spacing to Classroom Learning. In D.S. McNamara and J. G. Trafton (Eds.), Proceedings of the 29th Annual Cognitive Science Society (pp. 19–20). Nashville, TN: Cognitive Science Society.