Retrieval Induced Forgetting vs Facilitation


Ross Morrison McGill founded @TeacherToolkit in 2010, and today, he is one of the ‘most followed educators’on social media in the world. In 2015, he was nominated as one of the ‘500 Most Influential People in Britain’ by The Sunday Times as a result of…
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Are our memories strengthened by sleep, and if so, what can teachers do?

Retrieval practice can impair retention of competing information that is not episodically or semantically related to the retrieved item (Liu + Ranganath, 2021).

What is retrieval-induced forgetting?

Put simply, retrieval-induced forgetting is the phenomenon in which remembering causes forgetting of other information. Conscious remembering is retrieved through explicit memory, but actual forgetting occurs in our implicit (subconscious) memory.

Retrieval practice can be costly!

In October 2022, I published a summary of some research which suggested that retrieval practice is costly for some students. You can imagine my delight when the authors of this paper, Prof Xiaonan Liu and Yicong (Alan) Zheng got in touch to say ‘thank you’, and also share some new research on retrieval practice and induced forgetting.

Sleep-dependent memory

Sleep-dependent memoryIn the paper, Resurrected memories: Sleep-dependent memory consolidation saves memories from competition induced by retrieval practice (Liu + Ranganath, 2021), the research sought to understand why retrieving a past event sometimes enhances and sometimes impairs the retention of related information.

It’s worth stressing that the retrieval activity was monitored in ‘wake’ vs. ‘sleep’ intervals (sleep-dependent memory consolidation) to test the recall strength.

In this research, 78 students participated from the University of California. All students reported fluency in English and were randomly assigned to 2 groups (short delay versus long delay), with 39 people in each group.

Ninety-six scene images with 48 pairs of related words (nouns) and another 48 pairs of unrelated words were randomly associated.

The research analysed recall of non-target and control items to examine retrieval-induced facilitation and competition (see a graphical representation of the study procedure).

I’ve picked some highlights from the 10-page paper and provided some teacher questions below.

  1. Retrieval practice can then impair retention of related information that was not previously retrieved.
  2. Retrieving one item can lead to forgetting competing items due to interference or inhibition.
  3. Retrieval can facilitate the retention of untested items from episodic (autobiographical) context.

Recommendations for teachers?

Drawing upon the conclusion and general discussion posed inside the paper, I’ve posed several ideas for teachers to consider.

  1. If sleep improves retention, how can teachers influence parents to improve habits at home?
  2. Following sleep, should all exams be held first thing in the morning to help students recall?
  3. At a national level, is student performance worse in the morning or afternoon?

There is much more inside the paper, and the challenges for teachers and education leaders is how to use elements of this research to reshape how we might work given the current challenges and circumstances of schooling.

The research concludes, that sleep rescued, and even strengthened, memories that would have otherwise suffered from competition with practised items,

Download the full paper.