From gaze to insights: How eye tracking reveals mind’s process

Eye tracking technology measures where someone is looking in real time. Using cameras and infrared illumination to detect eye movements, an eye tracker gathers a range of core signals, including gaze patterns, blinks, and fluctuations in pupil size.

These core signals are then analyzed to uncover insights into human behavior such as decision-making, fatigue, attention, and memory. But how can the subtle motion of the eyes reveal the mechanics of the mind? This article uncovers the ways eye tracking bridges vision and cognition.  

Eye movements are goal-directed 

The visual world contains an overwhelming amount of information, but our ability to perceive and understand it is limited. At any moment, we can only take in and process a small portion of what's around us. The main way we choose which parts of our surroundings to pay attention to is through eye movements. These rapid shifts in gaze — called saccades — allow us to direct our focus toward areas of interest, while periods of steady fixation let the brain extract detailed information. 

Eye movement patterns not only reveal where we look but also offer clues about why we look there. While eye tracking is often described as a window into visual attention, it’s just as much a window into cognition. Our attention is closely linked to our goals: we look at what we need to see to solve a problem, make a choice, or complete a task. Whether we’re reading, searching, recalling a memory, or making a decision, our eyes follow our thoughts. 

Because of the eye-mind connection, analyzing eye movements can reveal what people are thinking, how they’re reasoning, and even when they’re uncertain or confused. In this way, eye tracking provides measurable insights into not just human behavior, but the underlying cognitive processes that drive it. 

What do eye movements mean? 

Eye movements like fixations (when the eyes pause on a spot) and saccades (rapid jumps between points) are shaped by the task or goal at hand. In this sense, how we move our eyes can reveal what we’re thinking or trying to do. However, not all eye movements are driven purely by internal goals. Sometimes, our attention is captured by external features — such as bright colors or sudden motion — through what's known as bottom-up processing. Even in these cases, though, the focus of attention still reflects a meaningful response to the environment. Thus, eye movements are never random. 

Because the eyes can only move in limited ways, the same type of movement can signify different things depending on the context. It's the underlying task or mental state that gives those movements meaning. The following are some general guidelines about the meaning of eye movements and related signals, even when the task or underlying intention is unknown. 

Fixations and attention 

When our eyes stop to focus on something—known as a fixation — that signals attention and intake of information. Fixations reveal which elements of a visual field are most important to the viewer. For example, in reading, fixations show which words or phrases take longer to process. In user interface design, they indicate which buttons or menus draw attention — or get ignored. Longer fixations often suggest more complex cognitive processing, ambiguity, or unfamiliarity. Shorter fixations imply automatic recognition or familiarity.  

Blinks and vigilance vs drowsiness

In situations where maintaining alertness is critical, such as in high-risk occupations or during extended driving periods, monitoring blink metrics could serve as an early warning system for drowsiness. Blink dynamic measurements enable the development of interventions or tools to prevent drowsiness-related errors. 

Saccades and information search

Saccades are rapid eye movements between fixations. These movements help identify search strategies and cognitive goals. For instance, in a visual search task, the pattern of saccades can show whether someone is scanning systematically or randomly, whether they're using top-down knowledge or relying purely on visual features. 

Pupil dilation and cognitive load

Pupil diameter changes in response to light but also reflects cognitive load. A larger pupil generally corresponds to higher mental workload. In problem-solving tasks, researchers track pupil dilation to assess moments of insight, confusion, or strain. This physiological response is tightly coupled with activity in the locus coeruleus-norepinephrine (LC-NE) system, which governs arousal and attention. 

Gaze patterns and decision-making

Decision-making is often accompanied by characteristic gaze sequences. For example, when choosing between two products, people tend to look back and forth between options before making a choice. The number and duration of these comparisons correlate with the difficulty and importance of the decision. Eye tracking has shown that people sometimes look at an option even after making a choice — suggesting post-decision evaluation or confirmation bias. 

From gaze tracking to intention-aware systems  

Eye trackers make it possible to collect detailed data on eye movements and draw meaningful conclusions — and even predictions — about human behavior. Building on this foundation is the emerging field of attention computing. By capturing and analyzing what users look at, combined with an expanded set of signals like posture, facial expression, and body movement, devices can gain a higher level of intuition and understanding of their users.

This paves the way for the next stage of interaction: perceptive technologies that respond to our gestures, expressions, and natural movements. Advanced sensors can interpret human behavior at a deeper level, enabling hands-free interaction, issuing safety alerts, preventing injuries, and driving digital transformation across industries. The potential applications are vast.  

References 

1. Spering, M. Eye Movements as a Window into Decision-Making. Annu. Rev. Vis. Sci. (2022)

2. Cori, J. M., Anderson, C., Shekari Soleimanloo, S., Jackson, M. L. & Howard, M. E. Narrative review: Do spontaneous eye blink parameters provide a useful assessment of state drowsiness?Sleep Med. Rev. 45, 95–104 (2019). 

3. van der Wel, P. & van Steenbergen, H. Pupil dilation as an index of effort in cognitive control tasks: A review. Psychon. Bull. Rev. 25, 2005–2015 (2018). 

4. Mathôt, S. Pupillometry: Psychology, Physiology, and Function. J. Cogn. 1, 16. 

5. Liversedge, S. P. & Findlay, J. M. Saccadic eye movements and cognition. Trends Cogn. Sci. 4, 6–14 (2000). 

6. Mahanama, B. et al. Eye Movement and Pupil Measures: A Review. Front. Comput. Sci. 3, (2022).