The Science of Learning
As Clive Shepherd writes, "cognitive neuroscientist Dr Itiel Dror of
Southampton University. Itiel is becoming a bit of a celebrity amongst
the e-learning community in the UK as someone who avoids the grand
theories of learning and concentrates instead on practical tips based
on what we know about the brain and how it works (assuming we really
do and this I must place on trust)."
Of course, the sceptical side of me says that this is something like
saying that so-and-so can tell us best how to win an auto race because
he's a mechanic. There is, indeed, a distinction between knowing how
something works and knowing how best to use it.
Reading through the points in thsi summary, they seem sort of right,
but not exactly right. Let me clarify them.
* The brain is a machine with limited resources for processing the
enormous quantity of information received by the senses. As a
result, attention is extremely selective and the brain must rely
on all sorts of shortcuts if it is to cope effectively.
My response: no criticism of this; it seems to be about right.
* Teachers/designers can adopt two strategies to reduce the risk of
learners experiencing cognitive overload: provide less information
(quantitative approach) or take much more care about how this
information is communicated (qualitative approach).
Well, you see now, this approaches the problem not from the nature of
the brain but rather from the nature of the information. And when we
look at the information as nothing more than a pile of stuff to be
processed by the brain, then sure, these are the ways to deal with it.
But the other way to look at it is to, as promised, look at it from
the perspective of neuroscience. What does the brain do in cases of
cognitive overload? This is important because, if we know how the
brain will adapt, we know how to shape our information (if at all).
This is the subject of the next few points, so I'll continue.
* It is easier for a person to focus their intention on the desired
point if there is minimal noise (other information) surrounding
it. Reducing noise also reduces context, so a balance needs to be
struck.
I assume he meant 'attention' and not 'intention'. In any case, I'm
sure there are all kinds of tests proving this, but I will point out
that the nature of the subject is a much more significant variable.
People are able to focus on things even in the most extreme of
circumstances if they are sufficiently interested. That's how you can
have kids playing video games even while the house is burning down
around them (I guess that's the sort of 'context' that would be
important). By contrast, if you aren't really interested in what you
are doing, the least amount of noise distracts you.
We know this because (as was just stated above) we know that the brain
is extremely selective and filters out stuff that isn't important.
Perspective matters. From the teacher's point of view, the content
(lessons or curriculum) is constant, while the level of background
noise is the variable. From the point of view of the learner, however,
the content is also variable. That's why you get two very different
interpretations of the same phenomena.
* Overload can be reduced by grouping items/steps (what Itiel calls
'chunking'). Grouping can be accomplished by placing
people/objects/events into categories, or by compressing a number
of procedural steps into one, automatic action. Visually you may
separate items by space, size or colour. Learners will naturally
employ grouping as a strategy, although they may do this
inappropriately and the process requires effort. Better for the
designer/teacher to present material ready grouped.
This is a good strategy and one I have recommended elsewhere to help
people write academic essays easily and proficiently (and without
notes, but I digress). I find it interesting, though, that he used the
DE design term 'chunking'. Maybe reading something other than
neuroscience?
Yes, there are different types of groups. Groups that make sense
conceptually, especially if linked to a larger framework, are better
(I would add that colour is rarely, if ever, a part of such a
framework).
But is it better for the teacher to present the material already
grouped? How does that follow? If the intent is to have the student
learn the information (ugh, bad terminology) then we must ask, is it
the groups that aide remembering and understanding, or the process of
grouping that does this? If it's the latter, then presenting the
information already grouped may help the teacher remember, but will do
nothing for the student.
Because, as I noted above, it is better if the groups align with a
pre-existing conceptual framework, it is better then if the student
does the grouping, because that way the process allows the student to
connect, in an organized way, new knowledge with existing knowledge.
* A side effect of grouping is that once the action is completely
familiar (that old 'unconscious incompetence' phase), the
individual finds it hard to explain how they do it; they lose
control over the process because it has become automatic (so old
hands may not always be the best teachers?). Grouping is essential
to our functioning, but there are obvious dangers, i.e. unhelpful
stereotyping.
Here there seems to be a confusion between grouping, as in the sense
of classifying different perceptual entities into types, and grouping,
as in the sense of combining several activities into one. Now this
isn't necessarily bad (I have said elsewhere that learning to read is
similar to learning to ride a bicycle) but can be very misleading
unless carefully explained.
I think it would have been better to present them separately.
There are mental processes that can become automatic. Add 1+1 for
example. One of these processes is 'categorization'. You look at a
bunch of things and automatically associate some with the others,
based on habitually formed patterns of association. In some cases,
such as grouping people by colour, this sort of automatic association
can be inappropriate.
There are also mental processes that constitute sequences of steps.
The steps involved in a logical derivation, for example. So a process
that actually involves multiple steps may be performed by an
experienced logician as though it were only one step (I called this
'skipping steps' in logic class and complained bitterly about it.
"It's obvious," said the professor. "Whaaaa?" I responded).
These are very different phenomena that are essentially the result of
the same neural process but which instantiate very differently and
need to be approached very differently. Kind of like the way the
steering used to recover from a spinout may be exactly the same as the
steering required to navigate a hairpin curve. Sure, it's the same
motion. But you would describe the two events very differently.
1. Individuals use top-down processing to reduce overload. This draws
automatically on their past experience of the particular context,
existing knowledge and intelligence and avoids them having to
evaluate all new information from the bottom up. An example would
be how people can easily read a sentence in which the letters in
each word are jumbled up.
Yes. But...
This is not 'top down' processing as traditionally understood.
There is a very large difference between inferring something on the
basis of similarity to a prototype (that is, apttern recognition), and
inferring something based on a general principle or rule. By 'top
down' we typically mean the latter. But when describing character
recognition, as in the example, we are describing the former.
I would also be wary of building the (Darwinian?) intent into the
process. People use pattern recognition. It reduces information
overload. But it is not necessarily true that people use pattern
recognition in order to reduce information overload. People use
pattern recognition because that's how neural networks work. Perhaps
evolution directed us in this way, perhaps it did not. Either way, our
use of pattern recognition in a particular circumstance is not caused
by some such intent. It occurs naturally, as though by habit.
* Designers/teachers need to take account of the way in which the
information is likely to be encoded and processed - it's not 'what
you teach' but 'what is learned'.
Except... it is very misleading to say that it's 'encoded'. Otherwise,
yes, there is a large distinction between what the teacher teaches and
what the learner learns (which is why information-theoretic and
transmission-theoretic theories of learning are wrong).
* Different parts of the brain specialise in different tasks.
Individuals can engage in more than one task at the same time, as
long as each uses a different part of the brain.
Of course, these parts of the brain form dynamically and according to
experience and circumstance, so there's no telling in advance, or in
general, what processes occupy the 'same' part of the brain and what
processes do not.
That's why I can read and write while listening to loud music, as I'm
doing now, while my father couldn't.
* It's a myth that we only use 5-10% of the brain - we use it all.
Correct.
* The brain continues to change throughout our lives, even though we
stop adding new brain cells in our early 20s. Some parts of the
brain are relatively hard-wired (through nature or nurture), some
very plastic. It makes sense to concentrate in recruitment on
finding those people with hard wiring which suits the job, because
no amount of training will sort the problem out later. (Itiel did
not go into detail about those capabilities which tend to be
hard-wired and those which are more plastic - this is clearly
important.)
The main part - that neural nets are plastic - is true and important.
It is also true that some parts are pretty much hard-wired -- good
thing, too, or our hearts wouldn't beat and our eyelids wouldn't
blink.
But as to how much this carries over into learning or into life skills
- this is very controversial. I can certainly agree that there are
people with currently existing wiring that may be more or less suited
to the job. That's no more controversial than saying people learn
different things. But to say that these capabilities are hard-wired is
much more questionable.
1. As you grow older the hard-wired capabilities persist - the most
learnable capabilities go first.
This is demonstrably false. For otherwise there would be no
incontinence in old people.
1. Language is more than just a means for expressing thought - in
many ways it is thought. If a person is not exposed to any
language in early years, then by the age of seven they are
incapable of learning it.
I doubt that this is uniquely true of language - it is probably true
for any pattern set. Can a person become fluent in mathematics despite
never having been exposed to numbers. Can a person become a musician
having never been exposed to tone and melody?
People who have not specialized in the nature of language typically
take language as a given - some sort of folk-psychological
representation of Chomskyian generative grammar. And then suppose that
this then must be the nature of thought.
Even if language is thought - which i would not grant for a second -
we still know nothing about the nature of thought if we do not agree
on the nature of language. Which we probably most emphatically do not.
* The two sides of the brain really do have different functions (I
thought this was just pop psychology). The left brain concentrates
on language and analytical skills; the right has the spacial
abilities. The left side of the brain controls the right side of
the body and vice versa. The left and right sides of the brain do
not interact physically.
They do interact, through something called the 'corpus callosum'. But
yes, the two sides of the brain do specialize, as observed. That said,
to my knowledge, this specialization is not hard-wired.
* The size of a person's brain is not an indicator of intelligence.
Within the normal variation of human brains, that is. My poor cat,
with her cat-sized brain, will never reach human intelligence. But
she's still very cute.
* 20% of your blood is in the brain.
Which stresses the importance of nutrition to brain function.
* You never lose anything from long-term memory, just the ability to
retrieve it. Retrieval is a function of how you encode memories /
the number of links you provide.
Well, yeah, in the sense that the connections that constitute the
long-term memory are basically permanent, more or less. But you don't
'retrieve' memory the way you retrieve a book from the bookshelf (even
though it feels that way).
'Retrieval' (properly-so-called) is a case of pattern recognition -
and the less salient a pattern becomes in the mind, the less likely it
is to be associated with a current perception.
* Working memory consists of 7+/-2 items (again I thought this was
pop psychology).
Yes. And there's that 'grouping' again, in a third guise. We can
remember things that are more than 7 words long by recognizing them as
coherent patterns. That's why I can remember something like 'Turn
right at the third light and then left at the second stop sign, then
go four blocks' even though it consists of 18 words (and 70 letters).
or 1-800-857-2020 even though it's 11 digits long.
What we put into working memory first depends on pattern recognition.
* To reduce cognitive overload, take out every word or picture that
is not necessary or relevant to your learning goals. Even then,
don't deliver more than the learner can handle (presumably by
modularising the learning).
This is effective only at the very gross level, and not particularly
useful as you get into finer details (and more precise definitions of
'necessary').
I have seen studies, for example, showing that a slide show with
bullet points is more easily remembered than a slide show with the
same bullet points and animated graphics.
I expect, though, that the placement of the 'NRC' logo in the corner
of the same slides would not have an impact either way.
I also expect that the removal of 'unnecessary' letters in the bullet
points would actually hinder memory. Fr exmpl, rmving mst f th vwls.
Thy r nt necsry in the snse that we cn stl rd the sntnce, bt they hlp
wth the grping.
So - better advice would be something like - present material that
accords (perhaps with some cognition) with patterns that will already
be familiar to the learner.
* Provide the learning when it is needed, not before.
Sure. But why? This isn't determined by whether it is necessary or
not, but rather, by whether it is salient or not.
* Be consistent in the manner of your presentation, e.g. the
interface.
This can actually be distracting, taken to extremes. That's why
documentaries switch from having a person talk to showing some nature
scenes with a voiceover to interviewing some other person.
* Be consistent in the level of your presentation, i.e. not too
complex, not too simple. Try to work with homogeneous groups;
better still personalise the learning.
Yes, but again, why? I would argue that this facilitates pattern
matching .
1. Engage the learner by grabbing their attention, allowing them to
determine their progress, providing constructive feedback,
introducing an element of excitement/surprise.
Again, this doesn't follow from the presentation above. What has
happened here is that some hackneyed (and vague) pedagogical tips have
been attached to some discussion of neural function, without a clear
linkage between them.
* Be careful of allowing the learner too much control over the
learning process if they don't have the metacognitive skills, i.e.
they don't know what they know and what they don't know, nor how
best to bridge the gap. Ideally help learners to increase their
metacognitive skills, i.e. learning how to learn.
This has utterly nothing to do with the brain theory discussed above.
If the content has more to do with attention than, say, distraction,
then taking control away from learners, even in areas where they do
not have skills, may cause more harm than good.
And what are the metacognitive skills. What is 'learning how to
learn', for example?
* Providing the learner with control over pace and allowing them to
go back and repeat any step is important.
Same point.
* The learning benefits by being challenging. Performance targets,
rewards and competition can increase the degree of challenge,
perhaps through the use of games.
And again, same observation. This doesn't follow from what has been
stated above. Sure, it's good advice (what Seymour Papert and James
Paul Gee call 'hard fun'). But why is it good advice. What else can we
learn about this piece of advice. What kind of games, for example (see
Aldrich on this).
Anyhow, those are my thoughts based on this reading of Shepherd's
article. I also read a bunch of Dror's publications online and
certainly have no quibble with his neuroscience. I just think that the
study of teaching and learning involves more than just neuroscience,
and that there are areas of complexity and potential confusion Dror
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