Methods - How do we do what we do?

In order to conduct our research in the best possible manner, we use differing (child-friendly) research methods. These different methods, and how they exactly work, will be described below. 


What Does An Infant Look At?

  • Eye-tracking

During some research projects a measurement is taken concerning where the baby is looking, using an eye-tracker. This is a camera which is fixed underneath a screen, where it can register the eye movements of the baby. The baby sits at the screen, sometimes in a child seat or on the parent’s lap. A series of pictures are displayed on the screen. The eye-tracker measures where, when and how long the baby looks at a certain image. This allows us to see what the baby finds interesting, and which information will be processed in the brain.

The eyetracker

In the picture to the right is the result from research involving an eye-tracker. The colour show which areas from the face the babies have looked at. The redder the colour, the more the child has looked at this area of the face. As you can see, children focus a lot on the eyes!

  Infants' looking behavior


Measuring Brain Activity Of Babies

Why do we use these methods by babies to measure the brain activity? In this manner we can gain insight into the processes that are in play within the brain, whilst the brain is processing the just viewed pictures, or the sounds obtained from listening to the spoken words. As the children are very young, and therefore unable to describe their experiences to us, it can be difficult to understand how children develop in this age period. With this child-friendly method, it is possible to obtain new insights because babies do not have to respond so verbally. This method is therefore used in different research centres across the world in order to obtain knowledge surrounding the development of children. 

At this moment, it is possible to measure the brain activity from babies in two different, and child-friendly, ways. 


  • EEG

It is possible to measure the brain activity through the use of an EEG (electroencephalogram). In order to do this, a sort of swimming hat is used (see pictures) that can measure the small brain signals produced by your baby during, for example, their viewing of different pictures. This method also shows just how quickly information is processed within the baby’s brain. 

A research study using EEG proceeds as follows. Whilst the baby is sitting on their parents lap, a sort of swimming hat is placed on their head. This hat contains a few holes, in which we will place a small about of gel. The gel is similar to gel that is placed on the stomach area whilst an echo is being conducted. The gel ensures that the brain activity can be measured. After this, we will connect the EEG-sensors to the swimming hat. The baby will be able to feel the swimming hat on their head, but will not be able to feel the sensors. The sensors only register the activity and are in no manner dangerous for the baby. It will take roughly 10 minutes to put on the swimming hat and set everything up. During this time, the attention of the child is diverted, for example by playing a game or offering them something to drink.

Cap with EEG sensors

When the swimming hat is correctly placed on the baby’s head, we will begin with the study. The baby will look at pictures on a screen. When the study is over, we will take the swimming hat back off the baby’s head. A little bit of gel will be left over in the baby’s hair, which can be washed out. We have baby shampoo and towels on site for this purpose. 

  Looking at the computer


  • fNIRS

Another manner to measure the brain activity of babies is through the use of functional Near-Infared Spectroscopy (fNIRS). This method measures, using light rays, which areas of the brain are active when your child is looking at the pictures.

A study using fNIRS works as follows. Whilst the baby is on their parent’s lap, a band will be placed around their head. This band contacts sensors used to measure the brain activity. These sensors are in no shape or form dangerous for the baby, and your child will not feel the sensors. After the band is correctly placed on the head, the study will begin. The baby will look at pictures on a screen.

Cap with fNIRS sensors