July 31, 2017 by
Eye-tracking has suddenly become a lot more interesting due to a flurry of acquisition activity by three of the world’s biggest technology companies.
Google was first, acquiring US start-up Eyefluence last October. Eyefluence specializes in eye-tracking technologies for virtual reality (VR) and augmented reality (AR) applications, and provides users wearing head-mounted VR or augmented glasses with the ability to use their eyes as they would a mouse.
They were quickly followed by Facebook’s acquisition of Danish Eye Tribe in December. Established in 2011, Eye Tribe specializes in consumer-orientated eye-tracking technology and has developed both consumer hardware in the form of a device that sits on your laptop, and software that allows developers to build it into their applications and potentially smartphones and VR headsets.
And then there’s Apple, who purchased 26-year old German SensoMotoric Instruments (SMI). SMI has developed a range of eye-tracking hardware and software used across the board, including VR and AR, clinical research, cognitive training, linguistics, neuroscience, in-car systems, physical training and biomechanics, psychology, and market research.
All three acquisitions were below the radar deals for undisclosed amounts of money. But when the billion dollar triumvirate are interested, you just know something is about to get exciting! The wheel has been spun and where the ball will land is anyone’s guess, but we can be safe in thinking it’s connected to AR and VR.
Why is eye-tracking so important? Vision is our most powerful sense, accounting for 70% of the body’s sense receptors. It provides us with an enormous amount of data about our environment, enabling us to react intelligently. However, it often overrules our other senses, leading to illogical thoughts and actions.
Our sense of taste in particular is often fooled by our sense of sight. Our eyes send signals to our brain before food even touches our lips. Our taste buds don’t stand a chance; we’ve already predetermined both the taste and flavor of what we’re about to eat or drink by what it looks like.
Food scientists have known about this for a long time. In 1988, Dr H.A. Roth tested a lemon and lime flavored drink, colored in various degrees of intensity. He then asked his students to taste each version. The stronger the color, the sweeter the drink was felt to be, but, he’d tricked them as the opposite was true: the weaker the color, the sweeter the drink.
Throughout time, our eyes have been regarded as the window to our souls. They’re thought to be our emotional gateway. But why?
Looking into another person’s eyes can tell us a great deal about their emotional state. If you’re sad or worried, you wrinkle your eyebrows which make your eyes look smaller. If you’re happy you raise your eyebrows which make your eyes look bigger and brighter. You also crinkle the corners of your eyes in a “crow’s feet” pattern which doesn’t happen when you’re faking it! Our pupils dilate in the dark, and when we’re aroused either positively or negatively, and contract in the light and when we’re uninterested. The size of our pupil is beyond our conscious control, and for this reason psychologists consider pupil dilation to be the truest sign of sexual or social interest.
Optimal pupil size is a trade-off between two factors: visual acuity and visual sensitivity. Visual acuity is our clarity of vision; how well we can see the details of whatever we’re looking at. Visual sensitivity is how well we can detect something that’s in our immediate vicinity. To do this well, we need to have both our eyes and pupils wide open, hence the connection between pupil dilation and arousal!
Vision enables us to perform two functions. The first is the ability to see our physical environment, and detect opportunities or threats. Our eyes are wide open in order to take in as much visual information as we can, so we’re in a heightened state of arousal!
Secondly, once we’ve identified something we find interesting, our eyes examine the item so that we can fully understand it. We’re seeking clarity, so our pupils dilate or contract accordingly, to let the right amount of light in and according to the emotions the item triggers, thus telling others whats going on in our mind.
Eye-tracking essentially measures our eye activity when we look at something in order to determine where we’re looking, at what, for how long, what we’re ignoring, when and how often we blink, and how our pupil reacts to different stimuli, thus indicating how we feel about it. Specifically, eye-tracking records our eye movements and gaze patterns. Basically, it analyses human processing of visual information, measuring attention, interest and arousal, making it an incredibly useful tool for research on human (and, increasingly, consumer) behavior.
How do eye trackers actually work? Data is collected using either a remote or head-mounted ‘eye tracker’ connected to a computer. There are many different types on the market, but essentially they consist of a light source and a camera typically a video camera. The light source (usually infrared) is pointed at the eye, while the camera tracks the reflection of the light source and changes to visible ocular features such as the pupil. The data is used to extrapolate the rotation of the eye and hence gaze direction. In addition, information such as blink frequency and changes in pupil size are also measured.
This data is then analyzed. The most common form is to analyze the visual path of a participant across an interface such as a computer screen. Each eye data observation is translated into a set of pixel coordinates. This then shows the presence of eye data points in different parts of the screen, determining which features were looked at, what features got attention, how quickly the eye moved across the content, what content was overlooked, and nearly any other gaze-related question. Data visualizations then show what people see and pay attention to through individual gaze plots and heat maps that show the combined gaze activity of several participants.
Eye-tracking technology has numerous applications, from entertainment to market research to assistive disability technologies and medical diagnoses and treatment.
Researchers can observe what our brains choose to look at. They can’t explain why our brain chooses to look at specific things, but they measure and record the sequence of visual pointing decisions our brain makes, and are able to infer what is visually important to people’s underlying cognitive processes.
Brands can use eye-tracking in a myriad of ways: to evaluate their products, packaging designs, advertising, websites, mobile apps and online and offline shopping behavior, in order to optimize the customer experience. It’s possible to measure both attention to brands and their key messages as well as the ease or difficulty of store navigation. Metrics include engagement (number of fixations, dwell time, % of time in an area), ease of processing (fixation duration), findability (time to first fixation and number of fixations prior to first fixation), order of processing (gaze path), comprehension (repeat fixations) and excitement (pupil dilation).
For those new to the technology, leading biometric research company iMotions has produced a helpful set of six tips for getting the best out of any eye-tracking research experience.
- Have optimal environment and lighting conditions
- Work with dual screen configuration
- Clean your computer
- Properly train all involved staff
- Use protocols
- Simplify your lab set up
Give it a go. All the signs are pointing to a future where few of our lives won’t be touched by eye-tracking in some form — especially if the triumvirate of Google, Facebook and Apple have their way!