Eye Movement Measures of Performance on Visual Search Tasks: Equating the Baselines of Task Performance

Previous research suggests that eye measures can indicate decrements in performance on a visual tracking task due to increased difficulty in task execution from fatigue-induced conditions (Van Orden, 2000). In order to examine the sensitivity of eye movement to increased cognitive workload as indicated by difficulty of task, we chose a visual search paradigm. Using a basic visual search task, we studied the effects of increased task difficulty on subject performance and their corresponding eye measures. Results show a decrease in performance as the number of objects on the screen increase. What results could be expected if differences in individual abilities to perform visual search were controlled? This experiment looks at one method that can be used to control for individual differences in visual search abilities.