Active Recall: How to Study From Your Lecture Notes (Step by Step)

What is active recall?

Active recall is the act of bringing information back from memory without looking at it. Researchers call it retrieval practice, and the improvement it produces is called the testing effect. Answering a flashcard, explaining a concept out loud, writing everything you remember on a blank page, or doing a past exam paper are all forms of active recall.

The opposite is passive review: rereading notes, rewatching a lecture, highlighting a textbook. Passive review feels productive because the material looks familiar, but familiarity is recognition, not recall. In an exam you have to produce the answer, so practising production is what transfers.

The key point for students is that active recall is not only a way to check what you know. The act of retrieving changes the memory itself, making it easier to retrieve the next time.

Does active recall actually work? What the research says

Active recall is backed by decades of experiments, and three sources are worth knowing by name.

Roediger and Karpicke (2006), Psychological Science. Undergraduates read short prose passages. Some reread them; others took free-recall tests with no feedback. In the second experiment, one group studied a passage in four 5-minute sessions (about 14 readings in total), one studied it in three sessions and was tested once, and one studied it in a single session and was tested three times (about 3 readings in total). Five minutes later, rereading won: 83% recall for the reread-only group against 71% for the group tested three times. One week later the result flipped: 61% for the group tested three times, 56% for the group tested once, and 40% for the group that only reread. The reread-only group had also predicted they would remember the most.

Dunlosky, Rawson, Marsh, Nathan and Willingham (2013), Psychological Science in the Public Interest. This review rated 10 common study techniques on how well they work across ages, materials and test types. Only practice testing and distributed practice received a high-utility rating. Highlighting, rereading and summarization were rated low utility, which matters because those are the techniques most students use.

Karpicke and Blunt (2011), Science. Students who practised retrieval remembered more on a later test than students who built concept maps of the same material, even on questions that asked them to make inferences.

What is the difference between active recall and spaced repetition?

Active recall is how you review: by retrieving instead of rereading. Spaced repetition is when you review: in sessions spread out over days and weeks instead of crammed into one night. The two are separate techniques, and they work best together.

The evidence for spacing is as strong as the evidence for testing. Cepeda, Pashler, Vul, Wixted and Rohrer's 2006 meta-analysis in Psychological Bulletin pooled 317 experiments and found that spreading out study sessions improves long-term retention. It also found that the best gap between sessions grows with how long you need to remember: to remember for a week, review after a day or so; to remember until a final exam months away, the gaps should stretch to weeks.

Flashcard apps such as Anki, RemNote and Quizlet combine both techniques: each card is a recall prompt, and the app's scheduler decides when you see it again.

Why does rereading feel like it works when it doesn't?

Rereading feels effective because of fluency: the second time you read a page, it reads more easily, and the brain mistakes that ease for knowing. Roediger and Karpicke's reread-only students were the most confident they would remember the passage a week later, and they remembered the least.

Active recall feels worse because retrieval is effortful and you notice every gap. That discomfort is useful information. A question you cannot answer tells you exactly what to study, which rereading never does.

How do I use active recall with a lecture transcript?

This workflow turns a single lecture into a set of questions you test yourself on over the following weeks. It takes about 30 to 45 minutes per lecture, spread across several short sessions.

1. Capture the lecture as a transcriptUse a transcription tool so you are not relying on handwritten notes. LessonScriptor, a Chrome extension, transcribes whatever plays in a browser tab: Moodle, Canvas or Panopto recordings, YouTube, or Zoom in the browser. Add a header when the topic changes and take a screenshot of important slides. Free mode listens through the microphone, so play audio on speakers at 80% volume or more; AI mode captures tab audio and works with headphones.
2. Clean and mark the transcriptWithin 24 hours, reread the transcript once, quickly. Delete tangents and highlight definitions, causes, examples and anything the lecturer said would be on the exam. This is the only rereading in the workflow, and its purpose is to find questions, not to learn.
3. Write a question listTurn each highlighted point into a question. Aim for 10 to 20 per lecture. Put the question on one line and leave the answer in the transcript, so you have to retrieve it.
4. Optional: draft questions with an AI chatbotIf writing questions is where you stall, export the transcript as .txt or .md and paste it into ChatGPT or NotebookLM yourself, asking for questions that stick to the text. Check every question against the transcript before you keep it.
5. Test yourself with your notes closedAnswer each question out loud or on paper without looking. Then check against the transcript and mark each question right, partly right or wrong. The wrong ones are your study list.
6. Schedule spaced reviewsMove the questions into Anki, RemNote or Quizlet as flashcards, or keep a dated list. Review after about 1 day, 3 days, 1 week and 2 to 3 weeks, and once more in the week before the exam.

How do I write good active recall questions?

Good recall questions ask for one thing, can be answered from memory in under a minute, and mix simple facts with explanations. A question like 'What did the lecture say about mitochondria?' is too vague to test; 'Why does the folded inner membrane increase ATP output?' is not.

Can ChatGPT or NotebookLM make active recall questions from my transcript?

ChatGPT and NotebookLM can draft questions from a pasted transcript, and this is a reasonable shortcut when blank-page paralysis stops you from starting. Google's NotebookLM is useful here because it answers from the sources you upload and shows where each answer comes from.

Three rules keep it honest. First, ask for questions only from the text, for example: write 15 short-answer questions using only this lecture transcript, and quote the sentence each answer comes from. Second, check every question against the transcript, because chatbots can invent details. Third, write at least a few questions yourself: deciding what matters is part of the learning.

This is a user workflow, not a LessonScriptor feature. LessonScriptor's role is to give you an accurate, structured transcript to paste.

How often should I review with active recall?

A simple schedule is enough for most courses. Each review is short because you only answer questions, not reread the lecture.

Does active recall work with ADHD, and how should I adapt it?

Active recall works for most students with ADHD, though the research is still small. A 2023 study in Frontiers in Psychology counted only three earlier studies on college students with ADHD: two by Knouse and colleagues (2016 and 2020) found that students with ADHD benefited from retrieval practice as much as other students, and one by Dudukovic and colleagues (2015) found no benefit. The 2023 study found that retrieval practice helped students with ADHD, but did not make up for weaker initial learning in unmedicated students. The practical implication is that the capture step matters: you cannot recall what you never took in, which is one reason a complete transcript is useful.

The technique also needs adapting to how ADHD attention works.

1. Keep sessions smallTen questions with a 10-minute timer beats a 2-hour session you never start. Stop while it still feels easy to start again tomorrow.
2. Cap new cardsIn Anki, lower the number of new cards per day. A backlog of 400 due cards is a classic reason ADHD students abandon spaced repetition.
3. Answer out loud or by movingSaying answers aloud, pacing while you recall, or explaining to a friend keeps arousal up and makes it harder to drift.
4. Start with an easy winOpen each session with one question you know you can answer. Getting started is often the hardest part with ADHD, and an early success lowers the barrier.
5. Use body doublingStudy with someone else in the room or on a video call, each doing your own work. Many ADHD students find it easier to stay on task with another person present.
6. Fix the capture firstIf you lose the thread during lectures, work on that before anything else. Our guide to focusing in online lectures with ADHD covers it in detail.

Frequently asked questions