Recent research suggests that memory formation and retrieval have slightly different circuits or paths in the brain (Roy et al., 2017). “There are differential circuits for memory retrieval and formation.” (Humphres, 2016). Research also suggests that retrieval (e.g. recalling information from memory) must be explicitly practiced, and retrieval practice differs from encoding practices (e.g. putting information in memory). Retrieving memories may help prevent the natural decaying of unused memories that occurs and protect memories from interference (e.g. new learning can interfere with past learning and take over the routes to the LTM) and decay (e.g. memories decay over time if they are not used).

In education, there is a general emphasis on encoding and storage practices such as reading a text, listening to a lecture, watching a video. Often, not enough time is given to retrieving, applying, and refining what’s been learned (e.g. taking quizzes, teaching peers, writing essays and creating mind maps from memory, etc.). Even if we are paying attention, rehearsing, replaying and storing in LTM – we may not have an available LTM as we haven’t established the retrieval routes. Our retrieval routes may be inaccessible unless we practice accessing them. Research also provides additional reasons to practice retrieval as retrieval may be a ‘fast track’ to consolidating the practiced memory in LTM (Antony et al., 2017). Moreover, retrieval practice, despite being effortful, can refresh attentional resources for subsequent learning (Pastötter & Bäuml, 2014). This benefit on subsequent learning is known as the forward testing effect – “forward testing effect refers to the finding that retrieval practice of previously studied information enhances learning and retention of subsequently studied other information” (Pastötter & Frings, 2019).

References

Inaccessible Retrieval Routes

• Roy, D.S., Kitamura, T., Okuyama, T., Ogawa, S.K., Sun, C., Obata, Y., Yoshiki, A. and Tonegawa, S., 2017. Distinct neural circuits for the formation and retrieval of episodic memories. Cell, 170(5), pp.1000-1012.
• Pastötter, B., & Frings, C. (2019). The forward testing effect is reliable and independent of learners’ working memory capacity. Journal of cognition, 2(1).
• Antony, J. W., Ferreira, C. S., Norman, K. A., & Wimber, M. (2017). Retrieval as a fast route to memory consolidation. Trends in cognitive sciences, 21(8), 573-576.
• Pastötter, B., & Bäuml, K. H. T. (2014). Retrieval practice enhances new learning: the forward effect of testing. Frontiers in Psychology, 5, 286.
• Humphries, Courtney. (2016, Oct. 14). Susumu Tonegawa studies how memories are stored and how they can be manipulated. MIT Technology Review. Retrieved from https://www.technologyreview.com/s/602558/tracing-a-memory/