Scanpath

A scanpath is the sequence of eye movements, including fixations and saccades, that a person makes while viewing a visual scene or performing a visual task. It captures how information is sampled over time and can reveal viewing strategies, attention allocation, and processing dynamics.

The concept is associated with scanpath theory, developed by Noton and Stark in 1971, which posits that perception unfolds through a series of eye movements that encode cognitive processing. In this view, fixations are the periods when the gaze is relatively stable and information intake is highest, while saccades are rapid shifts between fixations that move the gaze to new locations.

Measurement and data collection rely on eye-tracking technology, which records where a person is looking and when. Common measures include fixation locations and durations, saccade amplitudes and directions, and the resulting sequence of gaze points. Researchers may report scanpath length, fixation count, average fixation duration, and the order of interest areas. Data are analyzed with methods ranging from qualitative inspection to quantitative similarity analyses and sequence-alignment techniques.

Applications span several fields. In cognitive psychology, scanpaths help study scene perception, reading, and visual search strategies. In human-computer interaction and user experience research, they inform interface design and usability testing. In marketing and advertising, scanpaths are used to assess attention patterns to products or ad content. In professional settings such as radiology or pathology, scanpath analysis can illuminate diagnostic scanning behavior.

Limitations include substantial variability across individuals and tasks, sensitivity to instructions, and measurement noise. Inferring cognitive processes from scanpaths requires careful interpretation, and results are probabilistic rather than deterministic. Ethical considerations and privacy concerns also arise in collecting gaze data.