Why Eye-Tracking Research Seeks for a Second Dimension

Jürgen Bluhm has more than 25 years of experience researching marketing and virtual shopping with eye-tracking. His latest work integrates virtual shopping with eye-tracking methodology and other biometric measurements like EEG, GSR, NIRS, etc. He has been consulting companies worldwide in different areas of market research based on eye-tracking and biometric analyses and worked in Germany with Tobii, a leading provider of eye-tracking systems (Stockholm, Sweden). Moreover, he is teaching as a university lecturer at Campus M21 in Munich and the Munich University of Applied Sciences brand image research, advertising, brand tracking, advertisement pre-testing and post-tests as well as new-product research. We talked with Jürgen Bluhm about current applications of eye-tracking and why additional biometric data is becoming more important in this field.

What kind of research requires eye-tracking technologies?

Jürgen Bluhm: “Well, the field of non-academic applications of eye-tracking has become extremely wide. Well known applications include market research, usability, packaging, product labelling, advertising, movies, human-computer interaction but also human machine interaction for different devices. In academic research, eye-tracking is used – for instance – in psychology and neuropsychology. Researchers use eye-tracking to study different kinds of brain disorders, such as Parkinson’s disease and hemispatial neglect after stroke. Others use eye-trackers with patients who suffer from partial locked-in syndrome, providing them with a way to communicate. Eye-trackers are used to study attention in social contexts of children with autism spectrum disorder. It is possible to discover the earliest indicators of autism in order to help diagnose and initiate interventions. There are also labs that study visual attention, social interactions and reading behaviors in education environments.”

How is eye-tracking used in usability research such as websites? Is it possible to find out individual needs and emotions and if so, is it accurate?

Jürgen Bluhm: “I think this depends very much on the research. For example, if subjects get the task to ‘book a trip to Hamburg, Germany online’, then eye-trackers help us to understand how people search for offers, compare and book. Eye-tracking creates very nice gaze patterns showing where the subject has been looking and for how long, and if he or she needed to look at something several times. But here we have the problem of one dimension: there is always the possibility that the person did not understand the task or the information showed on the website. We’d like more information to help us find out if we placed specific information correctly.”

Photo: Jürgen Bluhm

What kind of research could use the combination of eye-tracking data with biometric data? Why is it important to gain both types of data at the same time?

Jürgen Bluhm: “From the eye-tracking point of view, this is a very hot topic since eye-trackers can only measure visual fixation and related data based on the eyes. Depending on the research topic, measuring only eye-tracking data can be insufficient. Sometimes, it is essential to include a second dimension in order to draw conclusions about the relevance of individual images. If a potential buyer looks at a product, he or she notices it, but you cannot make a statement about how buyers feel while they are looking at the product. It is the same in neuromarketing. Visual attention does not tell us if the advertisement creates positive or negative emotions, but can provide extra information to help us infer their reactions to the product. Other EEG activity can help us determine if an advertisement makes them feel confused or bored. For most of my customers, the inclusion of biometric data such as heart rate (ECG), brain activity (EEG) or the pulse becomes more and more important in research.”

Photo: g.Nautilus wireless EEG used with Tobii Pro

How important are wireless systems for current research?

Jürgen Bluhm: “That is very important. Tobii offers two types of eye-tracking systems: wireless eye-trackers, and remote eye-trackers. Remote eye-trackers are integrated in computer screens which is perfect for lab studies. Wireless devices are made for field studies where subjects for example have to shop something wearing eye-tracking glasses. Natural environments are becoming more important to research.”

Jürgen Bluhm: “There are many customers asking for both dimensions, eye-tracking and biosignal analysis such as EEG. This is why Tobii cooperates with g.tec extensively, because g.tec offers wireless EEG systems for all kinds of research. g.tec developed the g.EYEtracking Interface for Simulink that allows users to acquire eye gaze of the eye together with biosignal data. The signals can be visualized, stored and analyzed in real-time in Simulink as well as offline in Matlab.”

What does the future hold for eye-tracking?

Jürgen Bluhm: “From my experience, eye-trackers will be used much more in Virtual Reality. There are VR systems which include eye-tracking to improve the VR. The fovea of the human eye is the point for maximum visual acuity and color vision. The eye-tracker finds out exactly where this point is located at the moment and with that, the VR renders this point more clearly than the periphery. The VR system needs less memory and processing power. This is also a more realistic visualization which revolutionizes the VR industry.”

Photo: g.Nautilus wireless EEG with with OCULUS Rift