Research with children

Tobii eye-trackers are very suited for the testing of infants because the infants can simply sit in front of the screen and watch while being allowed moving space during the experiment. A parent is always present during the experiment and close to the child. During these experiments children sit in a tripptrapp chair or on their parent's lap. One experimenter sits with the parent and the infant while concentrating on the presented stimuli. Another experimenter controls the experiment from a separate room.

The laboratory environment is decorated in a child-friendly manner, with toys and a soft carpet to play or crawl on or explore. Before we start an experiment the parent and the child are given ample opportunity to get used to the surroundings. The parent is told more about the study while the child can play.

All studies are designed to be fun for children even when we intend to generate useful results. Children actually like to look at moving and colourful objects. By measuring their eye movements we try to find out how they perceive objects, how good they are in tracking these and how they interpret what is or what will be happening to the objects.

We try to keep sessions as short as possible and if the need arises we take a break (e.g., for feeding or diaper change). All experiments are completely non-invasive (i.e. we measure only signals outside the body). All research with children in the Language Acquisition and Language Processing Lab is approved by the ethics committee and of course conducted only with the informed consent of the parent.

Typical experiments with children are preferential looking experiments and habituation experiments. In the preferential looking paradigm a child is presented with a verbal cue (typically a nice female voice that says "Look, look at the running cow", or at something else) and two simultaneously presented pictures or videos. If the child understands the cue, then it will look mostly at the picture/video best representing the verbal cue. With the eye tracker we record the stimulus that the child is looking at for longer to discover what he or she understands.

Habituation studies are more suited for children that have little or no command of language. Using such children in experiments in a language lab serves to find out if these children already have an understanding of different concepts as a pre-cursor to being able to express such concepts in language. In habituation experiments, a child is first habituated to some stimulus (e.g., a picture or video). Once the child is habituated, that is, has gotten so used to the stimulus that it is not really interested anymore, a new stimulus is presented that differs from the previous one on a parameter exemplary of the conceptual understanding that the experiment tries to investigate. If the child notices the difference (i.e. has a grasp of the conceptual difference between the stimuli) it will become dishabituated meaning that it is regaining interest in the presentation and looks at it again (or longer). If the child does not note the difference, interest levels should remain low. With the eye tracker we measure how long the child looks at what (aspect of the) stimulus and so try to discover what she or he understands.

When a study is over, we can show you the stimuli that your child saw overlaid with a video of your child's eye movements (and can burn this on a CD or DVD as a souvenir). To thank you for participating we will give you a small token as a sign of appreciation of your participation.

These efforts bring us closer to finding out about how thinking and language develop. It can be surprising to learn how much your child already knows!

Interested in having you or your child participating?

To fill in our online volunteer form, click here! Note: Form does not function at present.

You can also use this form to ask us questions.

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