When the human brain recognizes anything — a face, an object, a location, a piece of information — it responds. That response is involuntary. It happens before conscious thought intervenes, and expresses itself in the eyes: where they look, how long they linger, how the pupils dilate.
EyeTrek measures those responses. Not to directly detect stress or lies. It detects recognition, and the signature of concealed knowledge.
The Concealed Information Test (CIT) has been the subject of peer-reviewed research for decades, across multiple countries and independent research groups. The core finding is consistent: when a person is shown information they recognize — even when attempting to conceal it — their physiological and cognitive responses differ measurably from someone with no prior knowledge of that information.
The CIT does not ask whether someone is lying. It asks whether their brain recognizes something. That is a more specific question, and its answer is reflected directly in involuntary eye behavior.
This is the science EyeTrek is built on. Not deception detection in the abstract, but recognition detection, grounded in a methodology that has been independently validated and peer-reviewed.
The practical implication is significant. A person can prepare answers to questions. They cannot prepare their eyes to not recognize something they already know.
EyeTrek measures two classes of involuntary eye behavior. Each is linked, through peer-reviewed research, to specific cognitive and physiological states associated with recognition and concealed knowledge.
Together, these signals provide a multi-dimensional picture of the subject's cognitive response to each stimulus. EyeTrek's proprietary machine learning analytics evaluate all signals simultaneously to produce its threat assessment.
These signals are captured using a standard computer display and a commercially available eye-tracking camera. No sensors, wires, or physical contact are required.
In addition to concealed knowledge detection, EyeTrek can evaluate responses to direct screening questions such as "have you ever?".
The Concealed Information Test works by presenting a subject with a series of stimuli: images, words, or other visual items. This includes items that are relevant to the issue being tested and items that are not.
EyeTrek protocols are built around the client's operational context. Each session covers 1–6 issues. Multiple issue and single issue questions are dynamically alternated within the session to strengthen the recognition signal and reduce the effectiveness of countermeasures.
EyeTrek's co-founder Professor Yoni Pertzov has spent over 25 years researching eye-tracking and concealed information detection at the Hebrew University of Jerusalem. His published work forms part of the peer-reviewed foundation on which EyeTrek's protocols are built.