Simply stated, someone who studies human behaviour and the brain (a Behavioural Neuropsychologist) can help you:
(1) select the best participants for an eye-tracking study,
(2) determine the number of participants required,
(3) design the eye-tracking task to get usable results,
(4) design task instructions, and
(5) understand how study results apply to the target population.
Why Having a Behavioural Neuropsychologist on Your Eye-Tracking Team is a Good Idea
I’ve had considerable experience with eye-tracking: constructing an eye-tracker from spare parts, creating calibration procedures, writing analysis software, and using the eye-tracker in multiple studies. Although my background is in engineering, more recently, I completed a PhD combining engineering, biology and psychology to create new tools to study brain activity and human behaviour. Since completing my PhD, I’ve seen my fellow engineers, computer scientists, and web gurus struggle to obtain clear, usable results from the latest and greatest eye-tracking equipment. In my opinion, the crux of their struggles lay in what they don’t know about behavioural neuropsychology– the science examining the relationship between the human brain and human behaviour. While I can’t quite call myself a Behavioural Neuropsychologist, I have trained with them and can describe some of the gotch-ya’s of behavioural research. This article describes why including someone with experience in the field of Behavioural Neuropsychology on your eye-tracking team is a very good idea.
Tracking Your First Eye
Imagine if you will, that an associate of yours has just lent you an eye-tracker and you’re keen on using it to optimize your web site. You want to know what people are looking at and you want to modify your web site based on this information. To investigate this, you sit a co-worker down in a chair in front of a computer and configure the equipment to track their eyes. Then you display your web site; the eye-tracker shows where they look when various pages appear. It also shows where you co-worker looks when they stare blankley ahead, confused and perplexed, asking you, “What should I do?”. 
Making Eye-Tracking Data Useful
While you might have been able to successfully track a few eyes while people viewed a few web pages, the process of obtaining useful eye-tracking results requires some thought and experience. Considerable thought and experience, actually. My recommendation is that you find someone who has a working knowledge of brain function and has done behavioural research to help you obtain useful data from your eye-tracker. This article is about why this is a good idea.
Let’s assume that your goal is to optimize your web site; to get as many people who arrive on the site to make a purchase, or read about and digest an idea. Without getting into the details of what eye-movement and eye-gaze means, let’s focus on the role of a behavioural neuropsychologist in the design of the actual ‘experiment’ that will help you optimize your web site. Read more…