Researchers can use electrodes to measure children’s brain activity as they complete tasks. Understanding this brain activity can provide clues as to how teachers might optimise the learning environment for children of different ages and abilities. In the first of a three-part series, cognitive neuroscientist Paul Matusz introduces the method and describes how it sheds light on developing cognitive skills.
Neuroscientists like me have been measuring the electrical activity generated by the brain with a method called electroencephalography (EEG) for almost 100 years. Electrodes placed on the scalp, held in place by a cap, pick up the activity of groups of neurons near the surface of the brain. EEG is non-invasive and safe to use with people of all ages. It is also a relatively cheap and portable system for studying how the brain functions.
“Recently, researchers have started to use EEG as a tool to understand children’s learning processes that occur in the classroom.”
EEG allows researchers to look at what’s happening in the brain during specific cognitive processes. It is possible to record both where in the brain the signal is coming from and when the neurons send the signal, on a very fine-grained scale of milliseconds. Integrating the where and when information has become popular recently. This has led to exciting discoveries about the development of various cognitive processes, such as attention, which is my own area of research.
Recently, researchers have started to use EEG as a tool to understand children’s learning processes that occur in the classroom. This is becoming a reality following extensive development of advanced EEG research with adults.
Running an EEG study
In a simple EEG study, participants may be asked to pay attention to a square as it appears on a computer screen. Analysis of the brain signals collected through the EEG cap reveals a sequence of cognitive processes. While observing a simple square on a screen may feel instantaneous, there are multiple steps in the brain’s processing. First, the brain analyses the square’s basic features, such as brightness. It then categorises the shape as a square, and eventually we consciously pay attention to the square to then store it in short-term memory. This all happens in less than a second.
The electrical activity recorded through the EEG cap during each process can be characterised as ‘components’. Components are patterns of positively and negatively charged electricity – waves that can be visualised to look like hills and valleys across the scalp (see image). Looking at how components change with age reveals information about brain and cognitive development that traditional measures cannot. Measures like speed or accuracy in a task, for example, are less able to provide insight into the number and duration of mental processes.
“Children aged 10 and under might benefit from learning settings that offer fewer distractions from the task at hand.”
The EEG component that occurs during focused attention on an object is called N2pc, and it originates in the visual cortex at the back of the brain. Studying the N2pc component has shown that adults can typically ignore highly distinctive objects – those that are brightly coloured, for example – to pay attention to objects important to their current goals.
So far, there is limited research into the N2pc component in children. Some evidence indicates that around age 10, children start to exhibit the N2pc response when focusing attention on an object. The pattern of activity appears over similar areas of the scalp in adults and children, but in children it usually happens more slowly than in adults. This suggests that adult-like attentional skills may be present but somewhat immature by age 10.
Using these findings in the classroom
This finding has potential implications for the classroom. Children aged 10 and under might benefit from learning settings that offer fewer distractions from the task at hand. Teachers could design the classroom so that children are able to focus attention on what they need to. Where possible, teachers could avoid using eye-catching visual displays, unless these remind children of the material they need to learn. They can also choose textbooks and design worksheets that contain just the relevant information, minimising any decorative elements. Teachers could aim to keep noise both inside and outside the classroom to a minimum. These strategies might promote learning while children continue to develop their ability to control what they pay attention to.
“Portable EEG will soon allow researchers to measure children’s brainwaves in school as they learn.”
It is an exciting time for EEG research. We are close to being able to measure a child’s attention to objects and events using EEG in a classroom setting, rather than just in laboratory studies. Portable EEG will soon allow researchers to measure children’s brainwaves in school as they learn. We will be able to test the effectiveness and consequences of strategies to improve attention, especially in children who may have attentional difficulties, and gain a better understanding of attention in the classroom.