Sunday, 13 May 2018

Learning Theory Pt 4: What is learning?

(This page is draft.  Please help us improve it by adding your comments (giving the paragraph number) at the bottom of this page.  The aim is to have a bare-bones introduction to the question 'what is learning?'.)

What is learning?

1  Looking from the outside

There are many definitions of learning, see these ten.
This one, by the authors of 'Make it Stick', is typical: “Acquiring knowledge and skills and having them readily available from memory so you can make sense of future problems and opportunities.”
That's what we see when we observe someone from the outside, but it doesn't explain how they do it.  To understand that we need to look inside the brain and see the actual physical process of making a long-term memory.

2  Looking from the inside

Learning in the brain happens when long-term memories are formed.  The links between brain-cells become permanently changed and the memory-pathway can be accessed at any time (so long as it is linked to prior-knowledge pathways)
"Cells that fire together, wire together."
The basic unit of the brain is the neuron, or brain-cell.  The process defined above implies a permanent  change in the brain with the new learning stored in an accessible way.  Looking at how the brain does this we see that the main change is not to the number of cells, but the connections they make.
Cells communicate with each other at chemical connections called synapses. Learning happens when some synapses are triggered into a new state - long-term potentiation.

3  Forming memories

Neurons:  brain cells

The way that the brain stores information turns out to be quite different from the way a computer stores it.  If you had a video camera and a bunch of hard drives, even the newest ones, you’d probably fill them up if you videoed your life over the weekend.  But the brain doesn’t ever get full, and the reason for that is that it stores the information in quite different ways. 


It is made up of brain cells; information is collected from other cells by the dendrites (left) and transmitted to others on the right.  When you're very young these cells have potentially 500 connections, so learning involves creating pathways which are preferred. Some of those 500 just fade away, but the preferred ones get stronger: and that’s what we call learning.


3.1  Chemical connectors - synapses

Cells are not directly connected, they have chemical-junctions called synapses. This diagram shows three brain cells joined together, (greatly simplified).  At the junction there’s a gap: a synapse.  The link is chemical with neuro-transmitters moving across the gap.   The reason why the brain has evolved (or was created) in this complicated way (rather than actually joining) is that it’s the way we learn. If you were born wired up, you wouldn’t be able to learn anything. At birth, a lot of the human brain is just sitting there, ready to be connected.

We can tell we have chemical links by observing what happens in our own brain.  If you wake up in the morning feeling a bit dull and you have some coffee, the caffeine boosts your neuro-transmitters and you wake up a bit.  Later on you're feeling wide awake and you have a few too many drinks, the alcohol suppresses your neuro-transmitters. Your speech may get slurry and you may lose your inhibitions (as the synapses from that area cease functioning!).

3.2  Long-term potentiation: the memory mechanism

This is the mechanism by which long-term memories are made. The synapses (gaps between brain cells) for the memory pathway become permanently changed, which means that the signal can flow easily along the path.

We can think about this in terms of gates. The signal arrives at the sending side of the synapse and causes neurotransmitters to be released. These neurotransmitters attach to the receiving side, triggering the signal in that cell.

There are two types of receptor on the receiving side: 
  • a 'small gate' which opens easily from the outside
  • a 'big gate' which can only be opened from the inside.
When the pathway is used repeatedly, the big gate is opened and remains permanently open. In other words, a long-term memory is formed.

This video below gives a technical explanation of this process.

This video gives a simplified version.



3.3  Short term memories

When we first start to learn something, we may appear to have formed long-term memories because we can answer questions later in the lesson.  However, these traces can fade completely if they are not backed up by repetitions to induce long-term potentiation.
These short-term memories are therefore just the early stages of long-term ones (not something different)

4  What are memories? 

Memories are not stored like they are on a computer. If you took 100 pictures all with blue in them and stored the images on your computer, the blue would be contained in every single picture.  However, we’ve got a part of our brain which detects different colours: blue, green, red. Every blue object in your memory will be connected to the blue area;  the computer is much less efficient than the brain (but much more accurate!).

This diagram shows the visual memory of a child who has a yellow cup (after seeing it several times). The small group of cells, represented by the yellow spot, is connected to the shapes that make up the cup, and to the colour of that cup. The ‘memory’ is simply a spot with connections, and so it takes a very small amount of space.   In a photograph you’d have all the information about the shape of that cup, but, in a brain-memory, you just have the links to the information.
Of course, no memory is only visual.  The child has physical sensations of holding and drinking and also an emotional response.  The full network of the memory has many components.



There isn’t one place in the brain for memories – they are simply links, so, for example, the memory for actions is in the same place as the action, while the names of things tends to be in the lower, left back part of the brain.  However, you have no sense yourself that this is the case!

4.1  Memory as a hierarchy

 You could say we have very basic shapes at the lowest level, and more complex objects are remembered just as the links to these basic shapes.  Clever eh!?


The spots in the ‘basic objects’ level in the diagram may represent your memories of table and chair, for example, and the spot in ‘complex objects’ could be your memory of ‘kitchen furniture’. So, everything is linked together in some sort of a hierarchy.
The knowledge in a student’s head (and in yours) is also hierarchical.  Sometimes students struggle for years.  Often the reason why, for example, they still can't do maths, is because the prior knowledge links were missing. The classroom research suggests that linking to prior knowledge is a good idea and a successful thing to do.   This means that the difference in students’ results between the teachers who link to prior knowledge and those who don’t, could be a whole grade.

4.2  Grandmother cells 

There is growing evidence that memory is structured as links. Researchers have found individual cells which respond only to one thing (for example: a picture of Jennifer Aniston on her own).  The term 'grandmother cell' is being used to label these cells - they are connecting point for all the components of a memory: the person, what they said; where you were, your emotional response etc



Further evidence comes from the observation that damage to certain small areas of the brain can result in the person being unable to make long-term memories.  This is not because the long-term potentiation has stopped working, but because 'grandmother' cells can no longer be formed.

4.3  Multi-sensory teaching

Because memories are networks of connections, the more the merrier!  If you only teach in words, your student will have mostly word-memories.  Adding some visual images (sometimes called 'dual-coding') adds an extra dimension.
Doing something practical or linking the learning to something exciting will also help.
However, as we will see in the section on Working Memory, it is important not to provide too much information at once.  Also, although doing something while looking at it and listening to the teacher's explanation is effective, expecting your students to read and listen at the same time is not.

4.4  Long-term memories are persistent.

Once a pathway is formed it is almost impossible to get rid of it.  memories you formed as a child, which you might not even think about for years and years, are sometimes immediately available years later.   People who have traumatic experiences would be really pleased to get rid of those memories!  
This can also tell us why people hang on to misconceptions and why it’s important to nip them in the bud as quickly as possible. (see the 'Feedback' section later on)

However, there is still sufficient space for us to carry on learning!

5  Forming long-term memories in the classroom

Sometimes we may feel that repetition might be a waste of time, because the students appear to already know it, because they’ve succeeded in the lesson. However, our own experience shows that students often seem to have forgotten what they appeared to have learned last lesson;  without repetition, the brain will almost ‘reset to zero’.  To secure the memory-pathway. you don’t re-teach the same material, the learners have to do the processing (which exercises the pathways).  It could be a plenary or questioning at the end of the lesson, it could be a recap or quiz at the beginning of the next lesson, or it could be a homework task which is repetition.
"Learning takes place through the active behaviour of the student: it is what the student does that they learn, not what the teachers does."

5.1 Performance v Learning

These terms are sometimes used to label the difference between the short-term memories in the lesson - where the student may appear to have learnt (because they can 'perform', but cannot perform a week later.  'Learning' requires repetitions.
Performance in the lesson is no guide to whether long-term learning has taken place.

5.2  Spaced v massed practice.

Normal teaching practice would be to teach your unit lesson by lesson, and the students apply the knowledge, and then you revise all the material at the end of the topic/unit: that’s called ‘massed practice’. By contrast, ‘spaced practice’ is: teach a bit, test, teach a bit more, test, review the bit you were taught first, retest etc. That works really well.
We know that building memories in the brain is completely different to computers, computers remember everything and they remember it first time. The brain has evolved, or was created, to forget everything that it only meets once.
You probably all have the classroom experience:  you teach something and the students even seem to understand it, and then next week they don’t even remember having done it. The memory seems to have been completely erased. Well, it’s not that it is erased, it was never formed.  
Now we know quite a lot about the memory forming process, we can make some 'rule-of-thumb' guidelines:

  • Teach the new learning (activating prior knowledge, presenting the material, setting a challenging task, and providing feedback).
  • Ensure at least three spaced repeats
  • Repetition 1 within 24 hours.
  • Repetition 2 within 3 days.
  • Repetition 3 within a week.

There needs to be a gap between the 1st activity and the 1st repeat so that a certain amount of 'forgetting' has taken place.  This can either be just a gap of time (the suggestion is at least 20 mins), or it can be the student doing something different for a while (see 'Interleaved Practice')
If first repeat is too soon, the brain effectively treats it as one visit. So if you did something at the beginning of the lesson and the students had to do something with it at the end; that would be a first repeat.  The first repeat is the most important because, if it was a few days before the next repeat, then the student may have completely forgotten.The brain is reset to zero, and those pathways are available for a completely different learning.
If we want to secure memories we have to structure the learning by giving our students the opportunity to process the same information on three separate occasions.  One at least 20 minutes apart, maybe for homework, certainly by the beginning of the next lesson, and then build in two more repeats before those pathways have faded.

5.2.1  ..but some of my students seem to learn without me doing any repeats!

The research suggests that all people learn in the same way. The reason why some people learn faster is because they actually do the repeats themselves, in a ‘mulling over’ process.  They tend to be students who are interested in the topic or have friends also interested.

6  What this theory can explain

This model (theory) of how memories are formed, and how they are links to existing memories, helps explain a great number of the things we see in classrooms:
  • students failing to learn due to lack of spaced repetition
  • students who 'can't do maths' (or another subject) due to lack of prior knowledge
  • students appearing to understand something one day, but to have completely forgotten by the following week
Using evidence-based methods, even without a theory, will improve the learning.  However, understanding this theory will help you choose the most appropriate method to use to solve the problem you see in your classroom and so significantly improve the learning of your students.  They can also understand why some of their students are failing to learn and be better equipped to help them.

7  In summary:

  • Learning involves making long-term memories.
  • Memories are links between neurons made by strengthening synapses.
  • The links require spaced repetition.
  • Memories are networks of links.  If prior knowledge is missing, memories cannot be formed.
  • Once formed, memories and habits are very hard to change.  Feedback is essential to ensure the right links are made.


12 comments:

  1. I found this to be an extremely informative and useful article. I genuinely feel that the language is conducive to understanding and not too technical or ‘jargon based’ at all. Any suggestions from my good self would only serve to weaken the premise!
    As well as being informative, it was extremely enjoyable to read!
    Perhaps an increased focus on the theory of learning should be taught as an independent, discrete, aspect of the a school syllabus?
    My own pupils would certainly benefit from such an understanding and hopefully generate greater independence!

    ReplyDelete
  2. Paragraph 4.1 "This means that the difference in students’ results between the teachers who link to prior knowledge and those who don’t, could be a whole grade." I think claims like this need to be more exact - over what period must the difference exist? what is a 'Grade'? Otherwise it could easily turn into yet another urban myth claim...

    ReplyDelete
  3. Yes - I agree. Links to 'Why don't Students Like School'. Video is helpful for busy teachers - could have a student / parent friendly version?

    ReplyDelete
  4. 1. Short term memory is impacted on by emotion and emotion will always come first. Thus is a persons, a learners, short term memory is filled with emotional issues then the cognitive space for learning is decreased and this impacts on the learning that can be engaged with and subsequently move into long term memory.
    2. Check your numbering – 5.1 is repeated (not the content but the numbering)
    3. Summary section –
    a. Spaced repetition – in repeating it is critical that the repetition, while essentially the same, is slightly different so that the learner is having to think and engage with the repetition so that it becomes more stickable. The balance between meaningless rote learning and connected automaticity. One is an end point and the other is a weigh point on the way to further learning.
    b. I disagree with the fourth dot point – ‘If prior knowledge is missing memories cannot be formed.’ Memories will be formed but they will be incomplete or flawed in terms of accuracy or completedness. As teachers it is essential that what we teach is correct so that as these memories are formed they are formed on accurate content. It is like building a flight of stairs – if you miss one or two steps – the stairs will still be built but they will not work properly and if you keep missing steps then the staircase stops being able to be used.

    ReplyDelete
    Replies
    1. Very helpful comments.
      1. I agree, but will be using 'working memory' as the space that can be overloaded. (It's the next section to be drafted.) here we are using 'short-term memory' to label those memories which start the long-term process, but are lost as it is not completed.
      2. Numbering changed.
      3. Useful points which need developing. I have not covered 'interleaved practice' either, yet. perhaps we limit this page to simply saying what learning is and have a later page - Building better memories - with more detail?

      Delete
  5. Hi Mike, nice and simple so far. Can I confirm who the articles are aimed at? I read them as introductions for 18 year old initial teacher trainees or pupils studying learning. Are you intending to structure more profound questions regarding practice in schools? If we are successful in our funding bid we will be working at a teacher level across Europe and inviting those with specialisms in teaching/learning to contribute to class practice. Is this where you are heading?

    ReplyDelete
    Replies
    1. "who the articles are aimed at?" EBTN has been running training sessions using similar simple models with all types of teacher. Always well received. See the stuff on 'Level of description' in Pt 3.
      " Are you intending to structure more profound questions regarding practice in schools?" Can you give examples?

      Delete
  6. Really informative. Could the repetition also take to the next level? I usually structure my lessons so they learn a concept then by the end of a lesson have to apply it. Then in future lessons we apply it to different contexts. I have never planning in this way before but I think it makes a lot of sense.

    ReplyDelete
  7. I found this particularly interesting, particularly about the grandmother cells- it explains so many of my students. This also explains why it is so important to teach SEN students with as many different styles as possible to help them to form connections. Spaced practice in tiny, tiny steps certainly has some success with my students. A truly inspiring read!

    ReplyDelete
  8. Really interesting and clear. Certainly would appeal to the healthcare professionals on my education masters programme as a way of linking their medical knowledge to teaching theory and practice. I wonder if we can link the cognitive psychology and neurology to some of the social science theories explicitly? Constructivism links well with neuroplasticity as each person will build on their own existing neural networks with additional pathways and interpret and access information in light of that.

    ReplyDelete
  9. The definitions of learning are interesting and useful. However, I would just say that they all put a rather positive slant on it. We perhaps need to remember that learning can also be negative e.g. children can "learn" that they are inferior to others if they are in classrooms that do not differentiate for them; children can learn that certain subjects are boring if they are not taught well.
    The definition I have carried with me for many years is that "learning is the residue of experience." I like the conciseness, the elegance and the neutrality of the definition.
    The science is presented simply enough for most of us to understand. As teachers, we need to explore its implications rather than needing it at a higher level of science (provided that simplifying the model doesn't corrupt it, which can happen).
    The point that memories, once formed, are very hard to change is a salutary one. I've been arguing for the teaching of correct spelling from the word go for that very reason - why ask children to "work out" spellings of words you know are going to be wrong, given that we know that this will form incorrect memories which will have to be changed? But I'm a bit of a lone voice here!
    Also salutary and interesting is the idea that we all learn in the same way and it is the fact that students who are motivated to do so actually manage the spaced repetition for themselves. This must have implications for students with special needs.

    ReplyDelete
  10. I agree with others who have written that this is presented in a clear, accessible, and jargon-free manner.

    Much is written about the importance of developing connections and I think it could be more explicit that these connections need to be broad, as well as deep. Arguably, ’prior knowledge’ encompasses anything a student has previously learning. However, too often I think teachers interpret ‘prior knowledge’ to be the pre-requisites skills and knowledge for a concept. For learning to stick, students also need to develop connections to: why it is important/ useful/ fun / interesting; how it can be applied; where they have seen it before (and are likely to see it again) in their daily life; and why it might be worth remembering.

    I do wonder about the use of the term short term memory in this theory. I know this was partially addressed in reply to Rebecca’s comment, however I have always understood ‘short term memory’ to be considered very short (i.e. measured in seconds, not minutes). To me, this means short term memories would not be particularly helpful for recall later in the lesson. However, I don’t know what a more suitable term would be and I appreciate the point about performance not being encoded into long-term memory.

    Grandmother cells were interesting and new to me. Is there any research on how they are formed that would be relevant to this theory?

    Finally, a small grammar point: In section 6, second paragraph, most sentences are directed towards the reader using ‘you’. However, the last sentence switches to ‘they’, which seems awkward to me.

    ReplyDelete