Abstract: A system and method is disclosed which detects a specific cognitive-emotional mental state (e.g., passion) in a subject. The system and method utilizes different Internal Personalized Explorer (IPE) stimuli subliminally exposed to the subject on a visual display. Following exposure, the subject performs a target-specific cognitive task and a related behavior (e.g., deciding whether a briefly displayed string of letters is a word or not, and pressing a button to indicate the decision). The decision reaction lime for the behavior is recorded in a computer database. The reaction times are interpreted quantitatively to detect the relative intensity of the specific cognitive-emotional mental state in the subject. A reaction time for a specific individual IPE that is shorter than the mean reaction time for an IPE that does not evoke the emotional state indicates that the specific individual IPE did evoke the emotional state in the subject.