Eye movements
parameters, mechanisms, and active vision
pp. 265-279
in: Psychiatry and neuroscience update II, Berlin, Springer, 2017Abstract
Human eye movements are essential for visual perception, as the physiological structure of the eyes limits high acuity and colorful vision to a small fraction of the retina. Measuring the dynamic interplay of fixations (i.e., the eyes are stable relative to an object of interest) and saccades (i.e., the eyes are directed to a new target) makes possible fundamental insights into the organization of vision. A complex interaction of several types of eye movements is required when performing different tasks, such as orienting in space, identifying objects, or interacting with persons. Here, we discuss the characteristics of fixations and saccades in the context of active vision, with particular focus on the relationship between the two parameters. Analyzing the duration of fixations and the amplitude of saccades during everyday activities can reveal insights into the processing of visual information, allowing an understanding of what details of the environment receive attention. In addition, by considering fixations and saccades in combination, it can be determined how such details were processed within the context of ongoing activities.