Humming in Sync: How Our Brains Can Learn So Quickly

What’s going on in the brain when we learn? (Apparently this one has learned to connect to WiFi.)

What’s going on in the brain when we learn? (Apparently this one has learned to connect to WiFi.)

The human brain’s ability to quickly analyse and absorb new information is remarkable.

Even something as apparently simple and well-practiced as reading these words and understanding them requires an impressive feat of mental processing.

What is it, though, that’s going on in the brain when we learn?

Professor Earl K. Miller, an MIT neuroscientist, outlines the problem:

“If you can change your thoughts from moment to moment, you can’t be doing it by constantly making new connections and breaking them apart in your brain.

Plasticity doesn’t happen on that kind of time scale.

There’s got to be some way of dynamically establishing circuits to correspond to the thoughts we’re having in this moment, and then if we change our minds a moment later, those circuits break apart somehow.”

To examine what’s happening when we learn something new, Miller’s research has looked at connections between the prefrontal cortex (in blue above) — where our executive control system resides — and the striatum (in red above), which is involved in memory and habit formation.

Previous studies from Miller’s lab have shown that when learning whether something is in a category or not, the striatum activates first, then the prefrontal cortex.

“The striatum learns very simple things really quickly, and then its output trains the prefrontal cortex to gradually pick up on the bigger picture.

The striatum learns the pieces of the puzzle, and then the prefrontal cortex puts the pieces of the puzzle together.”

The question is how these two areas of the brain are working together.

In new research in Miller’s lab, they examined how the brains of monkeys learned to categorise patterns of dots (Antzoulatos & Miller, 2014).

What the researchers saw was that, as the monkeys implicitly learned rules of categorisation, the electrical activity in their brains shifted.

The brain produced beta waves in two areas of the brain — the striatum and the prefrontal cortex — that were in sync with each other.

Miller likens it to a synchronised ‘humming’, albeit electrical rather than sound-based:

“There is some unknown mechanism that allows these resonance patterns to form, and these circuits start humming together.

That humming may then foster subsequent long-term plasticity changes in the brain, so real anatomical circuits can form. But the first thing that happens is they start humming together.”

This is the first time this has been seen:

“We’re seeing direct evidence for the interactions between these two systems during learning, which hasn’t been seen before.

Category-learning results in new functional circuits between these two areas, and these functional circuits are rhythm-based, which is key because that’s a relatively new concept in systems neuroscience.”

Image credit: Jose-Luis Olivares/MIT (my apologies for the childish joke Jose-Luis!)

How Children Learn the Earth Isn’t Flat

A classic study of childhood learning suggests true understanding comes from letting go of established preconceptions.

A classic study of childhood learning suggests true understanding comes from letting go of established preconceptions.

Imagine the revelations we all once absorbed: humans are descended from apes, numbers can be usefully replaced by letters to solve problems and the Earth is (near-enough) a sphere which rotates around the sun.

Despite their momentous importance for our understanding of everything around us, these facts can seem relatively trivial now, just as they were all in a day’s work when we learnt them back in school.

However obvious these ideas might seem now, there was once a time when we just didn’t get it, a time when maths was just numbers, humans were a species apart and the Earth was flat.

How children revise their understanding of the world is one of the most fascinating areas of child psychology.

But it is not just relevant to children; we all have to take on new concepts from time-to-time – even though they may not be as profound as the origin of the species.

It’s tempting to think that learning is largely about memory – especially since in the bad old days of education learning was largely accomplished by rote.

Of course fully appreciating complex ideas is about more than just memory, it’s about understanding.

But what mental processes take us from mere rote learning to genuine understanding?

A classic child psychology study carried out by Professors Stella Vosniadou and William Brewer provides a central insight into how we reach genuine understanding.

They used a cognitive psychological theory called ‘mental models’ which suggests we create, and then test, mental models of the way the world works in order to build up our understanding.

This theory implies there might be a series of intermediate points where we have some grasp of a concept, but it isn’t yet complete.

It’s these intermediate mental models that Vosniadou and Brewer wanted to look at for evidence of understanding in progress.

What shape is the Earth?

For their study Vosniadou and Brewer (1991) interviewed sixty children who were between 6 and 11-years-old.

Each was asked 48 questions, starting with the relatively innocuous: “What shape is the Earth?”, and then moving on to more probing questions designed to reveal the mental model of the Earth they were using.

While most of the children started off well by representing the Earth as a circle, it soon became clear to the researchers that children had all kinds of different mental models.

When asked what would happen if you kept walking and walking for ages and ages, many replied that you would fall off, which was surprising given that they thought the Earth was a sphere.

Some even said you would fall off onto another planet.

Others said that while the Earth was round we live on a flat surface inside it.

At first the answers seemed rather haphazard and inconsistent, as though children were just making them up.

But then, with further questioning, a clear pattern of responses began to emerge (brackets contain the number of children displaying this mental model):

  • Rectangular Earth: thought the Earth was a flat rectangle which you could fall off (1/60).
  • Disc Earth: thought the Earth was a flat disc which you could fall off (1/60).
  • Dual Earth: thought that one ‘Earth’ is flat which we are standing on and there is another ‘Earth’ in the sky that is round. Their answers revealed they saw the planet as flat when asked about ‘the ground’, but round when asked about ‘the Earth’ (8/60).
  • Hollow sphere: thought we live inside the Earth on a flat area (12/60).
  • Flattened sphere: thought that the Earth was a flattened sphere so that there were areas on the top (and the bottom) where people could live (4/60).
  • Sphere: the amount of children demonstrating the conventional view steadily increased across the age ranges examined (23/60).
  • Mixed models: the rest of the children either did not give consistent answers or models could not be constructed for them (11/60).

The fact that four-fifths of the children could be fitted into clearly defined categories shows how we are likely to construct the same types of mental models as each other, both accurate and inaccurate.

Understanding in progress

These results show the mind working to come to terms with a brand new concept that is fundamentally alien to the senses.

Our everyday experience suggests the Earth must be flat, otherwise, as gravity pulls us down, we’d slide off it.

This is our first ‘mental model’ of the Earth.

Then we are taught the Earth is approximately spherical and we try to update our original model but, it appears, for a period we get stuck in between.

It’s these intermediate mental models that point to how we try to make sense of new concepts by first trying to integrate them into our current understanding in some way.

The hollow sphere and the dual Earth models that children adopted are two examples of this.

Both are ways of trying to hold both the flat Earth and spherical Earth models at the same time.

What was holding back the children’s learning was their presupposition, coming from everyday experience, that the Earth is flat.

Until they let go of this old way of looking at the Earth, they can’t fully embrace a new view; they can only create an ugly, if occasionally ingenious, compromise.

Established presuppositions from personal experience are powerful factors which are difficult to let go of, even when contradictory evidence is staring us right in the face.

Sometimes real understanding is less about learning new concepts than letting go of old ones.

→ This article is part of a series on 10 crucial developmental psychology studies:

  1. When infant memory develops
  2. How self-concept emerges in infants
  3. How children learn new concepts
  4. The importance of attachment styles
  5. When infants learn to imitate others
  6. Theory of mind reveals the social world
  7. Understanding object permanence
  8. How infants learn their first word
  9. The six types of play
  10. Piaget’s stages of development theory

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Emotion, Learning, Attention and Perception

Don't Shoot!

[Photo by aigarius]

If you were forced at gunpoint to choose the part of the brain that plays the most important role in emotion, you might well plump for the amygdala. The amygdala is an almond shaped structure in the medial temporal lobe, roughly in the centre of the brain. While certainly not the only structure involved in emotional processes, it is the most extensively researched. Generally speaking, the amygdala is thought to play a role in mediating cognitive responses to emotional stimuli. Phelps (2006), in an Annual Review of Psychology article, provides an overview of the findings that have emerged.

Continue reading “Emotion, Learning, Attention and Perception”

Learning by example

On a similar theme to yesterday’s post comes this article by well-known psychologist Alison Gopnick. Its kernal is that kids learn better by imitating and refining what someone is showing them. She likens this method of learning to the way that a sports teacher might demonstrate a sport.

This effective method of learning is not normally employed for academic subjects. They tend to use ‘routinized learning’ method. This is a similar process to explicit learning, mentioned yesterday. There is simply not enough emphasis on the implicit methods of learning.

Imagine if you could watch a maths teacher trying to solve a problem they’d never seen before and explaining how they worked it out. Imagine if you could watch an English teacher trying to write an answer to an essay question about Shakespeare. Gopnik calls this ‘guided discovery’.

> From The New York Times

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