“Take care of all your memories. For you cannot relive them.” - Bob Dylan
I hope you love this one! I have enjoyed researching it. So far in the learning series we have discussed how learning works, how to prime prepare your mind to be receptive to new information and how to package information for it to be more memorable. Today’s blog is about how to lock away that memory for the long-term.
Before we go into long term memory, one truth we struggle with, is that memory is not static. Memories have drift over time. Our memories are reinterpreted with new experiences, context, and information. Your memory over time becomes a less faithful account of what happened and more how you in hindsight feel about what happened. There are therefore two important challenges to contend with, the naturally decay (forgetting) and reimagining of old material. Today we will be going through how your long term memory works, how sleep and revision can lock it away for the long term and end with practical tips as to how to keep memories alive.
What is our long-term memory
The parody character of a goldfish is an animal with no ability to remember things that happened even a short while ago, this would be us with no long term memory. Practically the long term memory allows us to benefit from a whole life’s experience, rather than just what we can store in our short term memory. New memories stored in our short-term memory decay and degrade rapidly and we are also much more constrained in terms of storage. Long term memory is more stable because physical changes to the brain help make it stick.
Consolidation is when memories move from the short-term working memory into the long-term memory. Long-term memory formation happens when neurons associated with the memory connect to make it easier to recreate that image/feeling.
Have you ever experienced a blackout? Blackouts are examples of when people's short term memories do not translate into long term memories due to excess drugs/alcohol, strong medication or brain trauma.
Sleep and memory
When we sleep, we are vulnerable to threats. What's so important that we would put ourselves at risk? Whilst sleep helps us save energy, regulate our metabolism and maintain repair, it is thought that sleep mostly has benefits for the brain.
In the brain sleep is a time to remove toxins, replenish energy but most importantly consolidating memories. It is most efficient to consolidate memories when external stimulation is low.
Sleep is more active than it looks. Rather than it being a period of low brain activity it is quite the opposite. Short-term memories are replayed multiple times until the related neurons start connecting. Strange dreams can occur in REM sleep because neurons associated with unconnected events might be firing at the same time. This replaying can happen over multiple nights. Rather than just freezing a memory, consolidation reorganises the memory so that the 'gist' can be extracted. The gist can be connected to existing memories to make them more relatable and fit within your larger body of knowledge. Like google, your brain is organising disparate information and making it mesh together so it can be accessed by cues. It is at this stage that your prior learning makes a huge difference and where creativity and insight can occur. Given the brain activity during sleep it is not surprising that many innovative discoveries have been discovered on waking. It also adds weight to the age old advice of 'sleeping on it'.
The analogy I can think of is file compression. We cant possibly remember everything from an experience, so we try and make data-efficient storage of events. It's like reading an executive summary rather than the whole document.
In experiments, learning in the evening (e.g. 9pm) before sleep resulted in less forgetting 24 hours later than learning during the daytime (e.g. 10am). How can we use that finding? Whilst consolidation is an addition to memory, as with much of nature there is a decay of what you remember. Memory operates on a use it or lose it framework, so things that you do not consolidate or use for many years will be harder to recall.
We forget things immediately. Within the day we learn something we can forget most of the information. This effect continues over time. Whilst sleep consolidates memory, it cannot retain it all forever. How do you help people remember things for a long time?
Thankfully a scientist called Hermann Ebbinghaus looked at ways to reduce the amount we forget. He considered the two pillars of long term remembering as
1) Packaging information so that they can be easy to recall (which we covered last time), including mnemonics, simple language and analogies
2) Spaced repetition, where you used mind maps or tested yourself at slowly increasing intervals.
Ebbinghaus noticed that spaced repetition not only helped people retain the material, but each time they practiced the slope of the forgetting curve became more shallow. When the learning material is recalled it goes into the short term memory again, restarting the process of consolidation, making the connections between the neurons even stronger.
It's worth noting that we find it easier to do actions and think thoughts that we have done repeatedly, because our brain builds strong connections between neurons that make electrical signals pass more efficiently. We see this not only in memories, but in habits and beliefs.
[ ] practical insights?
1) Sleeping, napping and relaxation will supercharge your learning
If you are not allocating time to them properly you are missing a trick. They are not unproductive, they allow you to get the most out of your hard work.
2) Spaced repetition is the most effective way to learn
For a given subject, little and often beats long last-minute slogs. Recalling and testing is the most efficient way to gain access to the material again. Memorising needs both intensity and consistency.
3) Have a very well kept to-do list
Your working memory is finite and is needed for consolidation. Do not make it compete with things you are not going to do right now. It is also important that your to-do list has what you will be doing tomorrow, you want to be diving straight into it tomorrow and not working out what to do.
4) Review and journal after a day of revision
At the end of a day's work, reviewing what you have done and reflecting on it, will make it more present in your working memory before you sleep, increasing the chance of consolidation.
5) Start making your practices harder
If you find your recall is good, try and edge up the difficulty of questions. Moderately challenging questions are more stimulating than easy ones. You should be struggling with questions or getting them wrong.
6) Vary your practice
Two groups of children had to get a bean bag in bucket 3metres away. One group practiced just throwing 3metres. Another group practiced throwing 2metres and 4 metres. The group that had the varied practice comfortably beat the group that only practiced 3metres. This type of effect occurs in many places. Varied practice exposes your brain to different skills. Building up your basket of skills will lead to better gains.
7) Avoid last minute cramming at all costs
If we think about this, the idea of doing an all-nighter before an exam seems especially unproductive given you miss out on the consolidation of memory.
Here are three take-aways before we pick it up next week:
A key step of learning is consolidating memories from your working memory into your long term memory. This is largely done while you are sleeping, when neurons are replayed to strengthen the connections between them.
As soon as we have learnt something, our memories begin to decay. Sleep helps stabilise some memories and that stabilisation is enhanced with spaced repetition.
We can integrate this knowledge into our learning by incorporating sleep and rest into our learning, conduct spaced, varied practice, have a trusted to-do list and journal about our learning that day.
Thank you for joining. Next blog in the learning series coming next week. Sign up to the subscription list on Blog | Deciders (hartejsingh.com)
Other blogs in the learning series: