pupillometriaa

Pupillometry, also known as pupillometría or pupillometry in some languages, is the measurement of the pupil’s size and its dynamic changes in response to visual, cognitive, and pharmacological stimuli. Modern pupillometry relies on infrared video imaging or dedicated pupillometers to track pupil diameter over time with high temporal resolution.

Common measures include resting pupil diameter, pupil diameter changes in response to light (the pupillary light reflex), constriction latency, constriction velocity, and dilation velocity. Data are typically expressed in millimeters and can be normalized to baseline size. Ambient illumination must be controlled during experiments, as lighting strongly influences pupil size. Calibration and quality control are essential to account for gaze position, blinks, and recording artifacts.

Applications span several fields. In vision science and neurology, pupillometry assesses autonomic nervous system function and the neural control of pupil dynamics. In psychology and cognitive neuroscience, pupil dilation serves as an index of cognitive load, attention, and affect. In clinical settings, it supports autonomic assessment and monitoring of drug effects on the eye. In human factors and driver monitoring, pupil metrics help gauge fatigue and workload.

Limitations and considerations include sensitivity to lighting conditions, age, iris color, medications, and ocular conditions. Accurate interpretation requires careful experimental design, standardized illumination, and appropriate data processing. While portable devices enable field use, they may trade some accuracy for convenience, and pupillometry should be interpreted alongside other physiological measures.