How the Brain Works: It’s all about layers part 1

The brain has a layered structure. You can think of it a bit like the layers of the Earth, from the crust, to the mantle, down to the burning, ancient core.

The outer layers of the brain process information without caring too much about goals or emotions. Some call it ‘cold cognition’. The inner layers increasingly process information in terms of goals and emotions, so-called ‘hot cognition’.

spider-1403889352yvkThe innermost layers coordinate with the functioning of the rest of the body. When I see a1280px-man_running_scared_cartoon_vector-svg spider, cold cognition recognises the visual pattern, hot cognition gets worried, the body is informed that its heart should race in preparation for fight-or-flight action, and cold cognition prepares the instructions to jump. The layers work together as an integrated whole.

This week’s blog explores how the outer layer, the cortex, works.

The Outer Layer (aka The Cortex)

As we’ve seen, the cortex is big in humans compared to other animals. The back and the front do different things.

The cortex, is a sheet of neurons for processing information. The sheet of neurons, 2 millimetres thick, is just a bit smaller than a sheet of A3 paper, and it needs to be crumpled up to fit it in the skull.  The sheet processes information without caring too much about the results. Where you are on the sheet doesn’t radically change how the information is processed, it just changes what is processed.

The back part of the cortex houses regions involved in sight (vision), hearing (audition), and the processing of space. Senses are processed along two routes. One route, called the ‘what’ pathway, tries to identify what things are. The other route, the ‘where’ pathway, processes where things are in space. You might want to combine this information: catch a cricket ball (howzat!) but don’t catch a snowball (duck!).

The motor areas are towards the front. At the boundary is an area for sensing the body, and the motor circuits for controlling parts of the body. Further towards the front are areas involved in planning, decision-making, and control. As we’ll see, these are still sort of motor circuits.

Between the back and the front, the sensory and motor systems are organised in hierarchies, moving from simple to complex. You can think of these hierarchies as being like a tower with many floors, with a separate tower for each sense. Each floor combines the work done below, and each floor has a farther view than the floor below. The lowest floor spots patterns in sensory information. The next floor up spots patterns within patterns. The next floor, patterns within patterns within patterns. Sensory and motor systems are trying to see patterns within patterns within patterns – and then make connections between the screenshot-2019-03-13-at-18-30-44patterns.

After a while, the upper floors of the towers might know a thing or two about what patterns are likely. Based on their knowledge, the upper floors like to make suggestions to the lower floors on what they may be perceiving (just to help out, mind). The upper floors of the towers for the different senses talk to each other, across cables strung between the upper floors, to see if they can agree what’s out there in the world. The upper layers are connected to the frontal parts of the brain, to pass on conclusions and see if their view fits with expectations.

The motor system has a hierarchy too, but its higher levels are different. They’re about patterns more distant in time. The lowest levels are about immediate actions. The higher levels are about more complex sequences of actions, further forward in time. The lowest level says ‘Do it!’ (primary motor cortex). The next layer says, ‘Prepare to do it’ (supplementary cortex). The next layer up says, ‘You may want to do it sometime in the future’ (prefrontal cortex). A complex sequence of motor actions to be carried out at some future point in time can be described as a plan. Pre-frontal cortex, the planning and decision-making part of the brain, can also be seen as the top of the motor system hierarchy, looking the furthest forward in time.

We saw in the section on evolution that humans have more cortex. This means that humans can build their towers higher than other animals. In their senses, humans can discern more patterns within patterns, more complicated concepts; and in their motor systems, they can build further forward, creating plans into the more distant future.

Read more at howthebrainworks.science!

Using research in the classroom: Teaching in a multi-linguistic classroom

roberto-filippiWelcome to our series in which we ask researchers to tell us how their research is of use and relevance for the classroom. Today, we are delighted to welcome Roberto Filippi, Associate Professor at UCL Institute of Education.

What is the focus of your research?

My area of research is second language acquisition with specific focus on the effects of bilingualism (or multilingualism) on cognitive development across the lifespan. This has become a very hot topic in recent years, mostly due to the increased multiculturalism in our societies. According to some reliable estimates, more than half of the world’s population is fluent in two or more languages – more than three billion people!  We can safely say that bilingualism is not an exception and studying multilingual speakers offers a unique opportunity to understand how language develops and what its interactions are with the rest of the cognitive system.

What led you to this area of research? 

Being the father of two bilingual children, I can’t deny that I have a strong personal interest. I began studying bilingual children more than 10 years ago in a London primary school in which the large majority of children were bilinguals. I directly experienced the challenges that teachers face everyday, but also the advantages that a multicultural / multilinguistic community can offer. Building a bridge between science and education was a very rewarding experience, an experience that I wish to continue even more here at the UCL Institute of Education.

Could you summarise your findings?

A decade of research in this area has shown many positive effects of second language development. I should say that studying bilingual / multilingual speakers is not an easy task. Second language learning occurs everyday and defining someone as “bilingual” does not explain the complexities of this phenomenon. Nonetheless, our studies try to take into account the many variables that might affect our findings like, for example, our participants’ linguistic experience, age of second language acquisition/exposure, levels of proficiency in both languages and socio-economic status.

Our studies have shown that bilingual children who learnt two languages from birth and bilingual adults who started to learn a second language much later in life, enjoy the remarkable ability to filter out sound interference when attending to a task – in our case the comprehension of speech. A possible interpretation of these finding is that bilinguals have to deal with two languages in a single mind. They need to filter out interference from the non-target language (i.e., the language that is not in use) and activate that target one (i.e., the language that one wants to speak or listen to). As a result of this intense and daily “brain training”, bilinguals may develop a stronger resilience than monolingual speakers to environmental distractions. Remarkably, in another study in which we used modern neuroimaging techniques, we found that the ability to control verbal interference in bilinguals is associated with a specific area of the cerebellum. This may indicate that the bilingual brain has a different functional and structural development compared to the monolingual brain, even in areas that were largely unexplored, such as the cerebellum.

What do you think this means for teachers in the classroom?

We are continuously bombarded by visual and auditory stimuli that affect our concentration. Our attention skills are very limited and prone to distractions that may impair our performance in everything we do. Classrooms are very noisy environments in which children need to learn in the presence of many environmental distractors. If our studies confirm that acquiring two (or more) languages early in life may enrich a capacity for filtering out distractors and learning more efficiently, I think we will offer educators and policy makers additional scientific evidence that multilanguage acquisition is beneficial for cognitive development.

If you could give one tip to teachers based on your work, what would it be?

Never discourage parents from raising their children in multilingual environments. Unfortunately, there are still cases in which educators advise multilingual families to raise their children as monolingual, to avoid “mental confusion”. This advice comes from early research showing that bilingualism was detrimental for a child’s cognitive development. However, this research has proven to be flawed. Decades of more rigorous and controlled scientific studies have not supported this view at all: there is no evidence that second language acquisition can impair development.

Therefore, I think it is the responsibility of the scientific community to provide research-based evidence and actively engage with education professionals. We need to work together to give our children everything they need.

You can read more about Roberto’s research in these papers; on bilingual advantage of language interference in adults, in children and on control of language interference.
Teachers and parents might also be interested in the many resources available on the Bilingualism matters website and the book Raising multilingual children.

Is classroom noise bad for learning?

In this week’s CEN seminar, Jessica Massonnié talked about her research looking at the effect of classroom noise on learning. Here she summarises her talk.

jessica-massonnieClassrooms are lively environments and, as you may remember from your own experience, they are also noisy. Teachers and students report classroom chatter, and noise coming from movement (i.e. scraping sounds from tables and chairs) as the most annoying sources of noise.

Previous research has shown that hearing a single person talking does, in most cases, impair performance (whether we measure attention, memory, reading skills or maths performance). However, more complex types of noise (i.e. when different conversations overlap or are mixed with noise coming from tools and devices, making the semantic meaning of the noise less salient) have been shown to have mixed effects, and do not necessarily impair performance. But we know very little about why some children are very impaired, while others do pretty well in noisy environments. That is what my work focuses on.

In my talk I presented results from a study carried out here, at the CEN, in collaboration with Cathy Rogers and fellow PhD students. We used recorded classroom noise, composed of a mix of babble and environmental noise, and measured its effect on children’s creativity. We found that children in their early elementary school years (below 8 years of age) with low selective attention skills were especially impaired by noise. However, older children, in their late elementary school years, and children with high attentional skills performed similarly in silence and noise. That is to say, noise did not have a negative impact for everyone.

A second study explored the same phenomenon, showing that children in late elementary school (from 8 to 11 years of age) had similar scores in silence and noise when they performed academic tasks (reading and maths), and it did not depend on their level of selective attention.

Measuring how noise affect children’s performance is however only one part of the story. Pupils are also more or less annoyed by noise, emotionally speaking. And this annoyance, perhaps surprisingly, often does not correspond to the effect we see on performance. In other words, some children feel very distracted by noise, even if it does not objectively impact their performance.

My current work is looking at the mechanisms behind children’s annoyance, with the optimal goal of providing some cues to improve their well-being.

* * *

If you are interested in the topic, I recommend the article: Sound or Noise? The importance of individual differences written by Lindsay McCunn.

If you have Netflix, I encourage you to watch the first episode of Explained, “Music”. It discusses the relation between sound and music, and how it is to stop “feeling” sound as music.

Finally, if you would like to receive quarterly scientific and artistic updates on the topic, you can sign up to the newsletter of the Pursuit of Silence.

The complexities of learning in multisensory environments

As a P8dks1l1hD student working on the effect of noise on learning, I am fascinated by the complex environment in which children are growing up. They are constantly exposed to multiple auditory and visual information (face to face conversations, TV, radio, books, background noise from the street…). I’m always wondering to what extent, and in which contexts, audio-visual information is beneficial for children, and in which contexts it can be detrimental.

In this blog, I’m going to summarize two talks that gave me some thoughts on these questions.

Anna Fisher (Associate Professor, Department of Psychology, Carnegie Mellon University) presented her work on the multiple “attention-catchers” in the classroom, and in particular, visual stimulation. Classroom walls are often very crowded and colourful: children’s work can be proudly displayed, along with posters to help remember letters and numbers, or the weather forecast which children enthusiastically update every day. By reproducing this visual environment in the lab, Anna Fisher showed that these can distract children from their lessons. In other words, it can be easier for children to focus on the teacher and relevant instructional materials if the classroom has a minimalistic design, with few decorations. In her study, this enhanced focus was associated with learning gains. Anna’s current work is also looking at the instructional materials themselves, questioning the relevance of illustrations in reading books: while multiple and colourful illustrations aim to be engaging, do they always help an understanding of the text? She suggests that their relevance should be critically questioned, to identify which illustrations provide support for comprehension, and which act as distractors, driving pupils’ attention away from the key points.

The main point here is to keep the overarching learning goal in mind. In that respect, Paul Matusz (Lecturer at the Institute for Information Systems at HES-SO Valais and Lausanne University, Switzerland) pointed out that being sensitive to multisensory information in the classroom can be a double-edged sword. Looking at posters on the wall while performing a learning task can promote learning, if these posters contain information that is relevant for the task at hand (e.g. multiplication tables). But if the information is not relevant (e.g. a poem that reminds a child of her holidays), it can potentially drive children away from their task. In other words, qualifying which information acts as “distractor” and which as a “learning help” depends very much on the task at hand. Children who are particularly sensitive to external information can be either especially advantaged or especially disadvantaged, depending on the relevance of such information. You can read Paul’s blog post, as well as his article written for children, to find out more about his work.

I particularly appreciated Anna Fisher’s and Paul Matusz’s work because they show us that complex psychological topics cannot be seen in “black and white”. Instead they encourage us to always consider the specificity of the learning context, and of each pupil. It also stimulates methodological innovations, revealing the potential for mixed-methods, in-between classic well-controlled laboratory research, and naturalistic investigations in the classroom.

You can find out more about Jess’ research from her interview with the Learning Scientists.  She works in the lab of Natasha Kirkham, whose research you can read about on this website here. You can also find out more about related research from other lab members on attention switching and multitasking.
Follow Jess on twitter @Jess_Masso and see her website here