Human memory isn’t organised like files on a computer. The brain organises memories with no logic, it cuts them up, adds irrelevant bits to them and organises them in multiple places with multiple meanings. It also alters and subverts memories to suit your own beliefs and preferences.
Short term and working memory are limited to about four items because they're always in use and work at a fast rate, rapidly processing and manipulating information with the effect that information is often disregarded or ignored. This can lead to confusion when stuff gets bumped out of the brain before it’s processed. ‘Why did I come in here?’ It can become overtaxed if too many demands are placed on it. This is called cognitive overload but it’s unlikely that pupils in a classroom will suffer this because a teachers planning usually organises learning into manageable chunks. The teacher may though! Having 30 kids asking you questions at the same time as you’re trying to do the register, misbehaving and running amok will cause you to have cognitive overload. However long term memory has vast capacity and you will never live long enough to fill it.
Memories are based on new connections between neurons supported by synapses. But if you want to learn a new thing you don’t have to keep learning the same things over and over because the short term memory simply accesses what the brain has previously stored. So say you want to learn a phone number. Your brain already knows what all the numbers are, you are simply trying to get it to remember a new sequence of numbers. This is called encoding and there’s strong evidence to suggest all memories are encoded in long term memory. To consolidate memory the brain shunts signals from the hippocampus where they are formed to the cortex. The approach of repeating and drilling isn’t essential for forming memory but it can help to encode and arrange it. So does this mean that if we repeat and drill things we’ll remember them?
Er yes and no. It does help but it’s much more complex. Remember our short term memory is aural, an inner monologue, but our long term memory is visual semantic, so anything that improves our ability to visually encode aural information will work well. Mind palaces work because they are getting us to create visual associations with aural inputs and teaching us to organise them. When we write down lecture notes we are actually using drawing (symbolic lines) to recode aural information into a visual semantic format. That's why drawing diagrams, maps and charts help. We are visual creatures. The power of art!
Remembering information is where retrieval comes in. The brains of your students have all the information you’ve given them in your lessons (if they've processed it) but it is their unique brain wiring, emotional attachment, motivation and experience that determines how they encoded them in the first place, where they were stored and how they will be retrieved. If your lesson went in the section marked ‘this is crap I hate this’ then it is unlikely to ever be remembered again. If a student was deeply emotionally upset at the time of learning they’re likely to remember the emotion not your lesson.
Encoding, storage and retrieval of memories are highly subjective and often chaotic.
If you want your students to remember things then by all means try drilling them. But if every teacher in the school is drilling students every lesson of every day then it will quickly lose effect because the brain will switch off and become bored by the same activity. Then again, it might make some students learn things more effectively as they get used to doing it because memory is not a one size fits all uniform process.
What is predictable is that people remember things more effectively through unusual diverse ways because our brains remember prominent, intense and relevant information more easily. This means we will be likely to remember key events, birthdays, parties etc. but also scary things, upsets and disturbances. Interestingly tests have shown that memory is context dependent.
You are more likely to remember things learned in unusual environments or if you are in the same place as when you learned the facts. (Make less able students do their maths test in their own maths room not the hall!). People use sensory associations to form memories and tests have shown that smells linked to learning can have dramatic effect. Mood, music and emotions are also important as I mentioned.
Memories are also sub-divided into episodic, procedural and semantic. Episodic memories are personal autobiographical such as remembering when you fainted in assembly. Semantic memories are factual whereas procedural are unconscious tasks and abilities. You’re more likely to remember episodic events than semantic information, because they are personal and semantic things aren’t usually emotionally experienced. When you say: I always remember that fact because my daughter threw up on me when I was doing it, you’re combining episodic and semantic memory.
What connects our memories are synapses. Think of them like the roads linking towns of information. The bigger and better the road the faster the information retrieval. Things that I feel are important to me will be given bigger and better roads and vice versa. Some people have bigger and better roads between certain areas of their brains. My friend is brilliant at remembering dates and times whereas I’m better at remembering events. This is the power of neural pathways or white matter in dictating what we are able to recall. Building better faster connections for your students is difficult and to an extent it is inherited but you can build them through repetition, visual semantic stimulation and motivation because making the pupils want to learn the information is important.
The brain also differentiates between familiarity and recall. Familiarity - we did this last term. Recall - I remember exactly how to do it or I know it but I can’t remember it. The long term memory is there, it’s just getting to it that’s hard and our brains have stored them under such brilliant terms as - things I’m good at, or things that smell like soap, or blue square things. The more connections we have the better. If the formula you’re looking for is stored under soap smell, things I’m good at and my blue pencil case then I’m more likely to remember it. This is why just drilling won’t always work. You need to stimulate as many things as you can in your classes brains and senses in order for them to remember and you need to keep doing them over and over because we are programmed to forget. The brain takes as many shortcuts as it can. It dumps things out of its memory quickly and ruthlessly. It knows what you’re looking for but it’s locked away in a cupboard downstairs and it can’t be bothered to get it. It wasn’t important so it forgot it.
Because of an effect called ego bias, people are more likely to remember things that make them feel good about themselves. In fact they’ll even alter information to suit their ego and ideas so making your students feel good about what they’ve achieved is important.
So memory is a very unreliable and peculiar phenomena. It isn’t uniform and it isn’t like an organised computer drive. It’s emotional, sensory and subjective. It doesn’t like to store lots of useless garbage it declutters and prioritises. It knows what it likes and how it works.
Drilling and repetition have an important role to play in learning things, but memory is more actively stimulated by personal experience, emotion and visual and sensory experiences. I might use drills to embed quick facts but sensory methods to embed larger theories and complex operations.
As ever in teaching nothing is easy
From the Idiot Brain by Professor of Neurology Dean Burnett