Optimising Recall for Medical Students
We learn a plethora of information during our time at medical school, and we need to make it stick - both for exams, and for our clinical practice in the future. There are several methods for improving your memory and ensuring that you recall information when required.
How Memory Works
- It is useful to understand a bit about how we form and solidify memories before focusing on how to improve recall. There are several steps involved in this process:
- When we experience the outside world, we are constantly taking in new information through multiple senses - visual inputs, auditory inputs, tactile inputs and often olfactory inputs. For example - your first time on the ward you may see the bustling movement, hear the sounds of the ward (often alarms) and smell one of several unpleasant odours. Our brains encode this information and processes it so that it may be stored for retrieval later.
Semantic encoding is when these sensory inputs are then associated with a specific meaning. Multiple studies have demonstrated that attaching meaning to new information (encoding them semantically) improves recall. For example, associating a disease with a specific patient you have seen with that disease will help you to remember key aspects of the disease.
- Memories are stored as connections between neurons in the brain, which may later be retrieved.
Information is initially stored in short-term memory, or working memory. This form of memory has a relatively small capacity of approximately five to seven items; more information can be stored using chunking (e.g. grouping numbers together in a phone number). Short-term memory is only stored for a short period of time, thought to be between fifteen to thirty seconds. An item may be kept in working memory for longer using rehearsal (e.g. repeating a phone number over and over). Counting backwards in 3s (the Brown-Peterson technique) is a way of ensuring that items do not remain in short-term memory, by preventing rehearsal.
- Long-term memory has a much larger (almost limitless) capacity and can last for a lifetime. There are two types of long-term memory:
- Explicit (declarative) - semantic (knowledge), episodic (experiences)
- Implicit (non-declarative) - procedural (skills), emotional
The retention interval is the period of time between learning information and being asked to recall it. During this time, information is consolidated; this particularly occurs during idle time and during sleep. Consolidation may be disrupted by learning new information. For example, if you were to participate in a resuscitation of a cardiac arrest and then debrief about it, hearing others’ accounts of the incident can disrupt your own recollections of the incident. This is known as retroactive interference.
- When we retrieve a memory, the brain pulls the memory from the connections that have formed. Information retrieval is the main limiting factor in memory, rather than storage capacity. Cues, such as visual or auditory cues, can aid in retrieval; if we smell a scent or hear a song that reminds us of a specific situation, then our ability to recall the situation will be greatly improved.
Repeated retrieval of information can strengthen connections and solidify memories. This is the underpinning concept behind the benefits of self-testing using memory devices, questions and flashcards.
Interestingly, repeated retrieval can also alter memories and make us put weight on certain aspects while underplaying others. Similarly, retrieving distant memories can cause them to be altered. For example, an often-told funny story can slowly change over multiple retellings until we ourselves believe the current telling to be a true recollection of events.
Setting Yourself Up for Success
Based on the concepts above, there are several things that you can do in order to improve recall.
Understand the Big Picture First
- While it is possible to rote-learn large amounts of information, it is much easier to remember these pieces of information if you understand how they integrate into the larger structure of what you’re learning. When starting a new topic, try learning the big picture first - how the topic is structured and how the elements interact. When you subsequently start reading about the details, it will be easier to form connections between ideas and you will be more likely to remember the key facts.
Make Notes Less Easy
- Many medical students write notes that they can then return to review later with the goal of optimising recall. There is reasonable evidence that handwriting notes improves recall - in a Princeton university study, students using handwritten notes performed better on conceptual questions than those taking digital notes.
If you’re writing notes digitally, consider using a bad font such as Comic Sans or Bodoni MT - two studies suggested that using such fonts improves recall. This is thought to be due to the difficulty of reading the notes, resulting in more mental work and more active attention.
- It can be tempting to multitask while studying - talking to friends, checking social media or watching a video. However, dividing attention significantly reduces our ability to recall information. In a study of forty-eight undergraduate students, accuracy of recall in a standard recognition test was reduced if the memory test was taken while simultaneously performing another task. This means that when trying to learn information, it is best to be in an environment free of distractions, focusing only on the task at hand.
- Focused study time is the time that we spend in the books, actively studying and testing yourself. In order to consolidate memories, we also need ‘diffuse’ study time - this is time that we spend taking breaks and allowing our mind to be idle. It is during this idle time that the brain is able to make connections between pieces of information, log ideas into memory, and create new insights. By focusing for too long our ability to lay down new memories can be adversely affected.
Consider using the pomodoro technique - focused studying for twenty-five minutes, followed by a five-minute break. During the break, reward yourself with something small, such as a snack, song, video or moment of mindfulness. This cycle can be repeated, using a timer to ensure that you keep to the schedule.
Get Enough Sleep
- Similar to taking a break, sleeping stabilises and solidifies memories. In two studies of healthy participants, recall was greater following sleep when compared to a day of wakefulness. Additionally, sleep deprivation significantly impaired attention, short and long term memory as well as concentration.
Naps can also be useful for consolidating connections between ideas. In one study, a 90-minute nap was associated with greater associative memory (remembering word pairs) but not item memory (remembering individual words) when compared to not taking a nap.
Get Some Exercise
- A meta-analysis showed that acute exercise has a significant positive effect on short-term memory, while longer term regular exercise improves long-term memory. This is thought to be due to the activation of cellular signalling pathways involved in the processing of memories and partly due to the exercise-induced secretion of cathepsin B, a key protein involved in memory processing.
Methods for Remembering Facts / Lists
MnemonicsMnemonics are a group of different memory devices that can be used to promote recall of difficult concepts. Examples of mnemonic devices are:
- Acronyms - e.g. ESCAPPM organisms
- Expression mnemonics - e.g. cranial nerves sentences
- Music mnemonics - e.g. the alphabet song
- Rhyme mnemonics - e.g. remembering which months have 30 or 31 days
A commonly used mnemonic device in medical school is acronyms. . Acronyms use the first letter of each word to create a shortened representation that can then be used to jog your memory about each item on the list. For example, the ESCAPPM organisms are organisms with inducible beta-lactamase activity that is chromosomally mediated, meaning that they can initially appear sensitive to beta lactams and later become resistant. The acronym stands for: Enterobacter, Serratia, Citrobacter freundii, Aeromonas, Proteus, Providencia, Morganella morganii.
Expression mnemonics are also commonly used in medical study. This involves the creation of a sentence using the first letters of each word. An example is the cranial nerves:
On Occasion Our Trusty Truck Acts Very Funny Very Good Vehicle Any How.
This is a mnemonic to remember: Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Accessory, Hypoglossal.
- This method involves creating a story that is meaningful to you in order to help the concept to stick. For example, if you wanted to learn the words potato, cemetery, penguin, floorboard, rubber you could create and memorise the following sentence:
The rubber floorboards of the cemetery felt like potato under my penguin feet.
What a memorable sentence!
- This method is slightly more involved, however is much more effective in optimising recall. The memory palace uses spatial memory by associating an object with a location. Essentially, you will mentally place representative objects around a room to remind you of the items that you need to remember.
- In order to get started with the memory palace method, try the following:
- Create a list of things to remember - this works best when trying to remember large numbers of words or terms.
- Use mental images that remind you of each item on the list - for example, a tiger for the thyroid, a toaster for the thymus and a book for the sternum. Choose the first image that comes to mind.
- Imagine a familiar place, such as your bedroom, kitchen or bathroom.
- Mentally imagine each of the images inside the place. Ideally, imagine each image in the corner of the room.
More objects can be placed in different places (e.g. above the fireplace, next to the doorway) and the room can become more full with items - at times the method can be used to remember hundreds of words.
When you need to recall the information, imagine walking through the room and seeing the objects you placed - hopefully each object will remind you of the word you have associated with it.
More comprehensive guides to using the memory palace are available if you would like to learn more about this method.
Methods for Remembering Concepts
Concepts can be more difficult to commit to memory, particularly if the concept is complex. Several methods may be used to optimise our recall of concepts.
- Analogies are a commonly used method of understanding new ideas, by relating an unfamiliar concept with a familiar one. By drawing parallels between a concept that you know and a new concept, it is possible to more rapidly understand the key ideas underpinning a new concept.
A classic example of an analogy in medicine is about the heart. The circulation is a series of tubes like a plumbing system, with the heart serving as the pump. The cardiac conduction system is like the electrical wiring. It is often useful to explain the various specialties to a patient by describing a cardiologist as the plumber, an electrophysiologist as the electrician and a cardiothoracic surgeon as the carpenter when it comes to dealing with the cardiovascular system.
In a study of nearly two hundred adults, those who learned information using analogies performed superiorly in immediate and delayed recall when compared to those who learned without analogies (Halpern). Those who learned using analogies were also more likely to be able to infer new information about the topic, and create their own analogies about it.
- Drawing a mindmap is a way of relating ideas in terms of their hierarchy. For example, a mindmap may explain the different types of lymphoma and how they develop from B or T lymphocytes and their precursors. Mindmaps tend to start from a key heading at the center of the page and radiate outward.
Creating a mindmap about a topic can improve our overall understanding of the structure of the topic, and leave an imprint in our minds that can stimulate recall. In order to improve recall, try redrawing a mindmap from memory and then comparing your copy to the original mindmap.
- A flowchart is a visual representation of a process that includes multiple steps. An example of a flowchart would be the hypothalamic-pituitary-adrenal (HPA) axis, with all of the hormones and inhibitory effects involved. Flowcharts provide a simple representation of a complex process that make it easier to understand, thus promoting recall. Again, you can optimise recall by trying to redraw a flowchart from memory.
One of the more effective ways of improving your memory of a topic is to test yourself. Retrieving a topic from your memory repeatedly (known as practicing retrieval) improves learning more than just studying the same information over and over (Karpicke & Blunt).
- There are several ways to test yourself on content and practice retrieval:
- Post-study recall - after a study session, attempt to remember the key points that you have learned. This may be augmented using the split page or Cornell note-taking methods.
- Mnemonics - use existing mnemonic devices (e.g. acronyms or expression mnemonics) or create your own. Practice recalling what the acronym or expression stands for.
- Mindmaps / diagrams - practice redrawing a mindmap or diagram from memory, and compare this to your notes
- Question banks - use past questions and practice questions to prompt retrieval of information that you’ve already learned. In order to solidify this, try then retaking only questions that you got wrong.
- Flashcards - use existing flashcard decks or make your own. Find a flashcard service that uses spaced repetition in order to optimise your flashcard review sessions.
Use Spaced Repetition
- If we were to read about a new topic once, it is likely that we would forget most of the information after even a few hours. The more times that we relearn the same information, the more likely we are to retain it. This concept is illustrated using the Ebbinghaus forgetting curve:
By reviewing information multiple times, we are less likely to forget it over time. This repeated review and recall cycle works best if each review is spaced out in time, rather than reviewing the same information multiple times in quick succession (Karpicke & Bauernschmidt). Ideally each review should happen when we’re about to forget the information.
- Teaching others is one of the best ways to learn and improve recall. There are several ways to do this:
- Join a study group - this will give you the opportunity to both learn from others and teach others.
- Tutor your peers - many universities have informal opportunities for teaching medical students in earlier years.
- Journal clubs - if your clinical team at the hospital has a journal club, you may be asked to find a paper and present it.
The benefit of teaching others extends to expecting to teach - in a study of students learning written material, recall was improved when students were told that they would be teaching others, compared to being told that they would take a test on the subject.
If you don't have any opportunities to teach, try using the Feynman technique. This involves imagining that you are trying to explain a concept to a twelve-year old child. Use the simplest language you can, and illustrate the concept using analogies and metaphors. This can help to solidify the concept in your long-term memory.
Want more info like this?
- Your electronic clinical medicine handbook
- Guides to help pass your exams
- Tools every medical student needs
- Quick diagrams to have the answers, fast
- Quizzes to test your knowledge
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