Eye trackers measure a range of
aspects of body language, or more specifically, “eye language” that provide insights into the
user’s state of mind. One of these is ocular vergence, which is tracked by measuring the
inter-pupillary distance. When the eyes move apart (divergence), it can signal that the user’s mind
is drifting, losing focus, or lacking concentration.
Eye trackers also monitor frequency of blinks, which can reveal information about the
user’s mental state. Delayed or “attentional” blinking is indicative of mentally taxing work, while
low-frequency blinking indicates deeper levels of concentration. Conversely, high frequency blinking
is associated with boredom, drowsiness and low concentration levels.
Another body metric that can be measured is the distance between the eyes and the
screen, which reflects the user’s posture. Leaning forward is often a sign of positive resolution or
a higher level of interest, while leaning backward may suggest negativity or an inclination to avoid.
By analysing these various aspects of eye language, eye tracking can provide a more nuanced
understanding of the user’s behaviour and mental state.
