Time course of information processing during scene perception: The relationship between saccade amplitude and fixation duration

Abstract

2005): Time course of information processing during scene perception: The relationship between saccade amplitude and fixation duration, Visual Cognition, 12:3, 473-494

Examining the influence of task set on eye movements and fixations

“…Likewise, in a preference rating task where participants had to choose which of ten paintings they preferred, Antes (1974) found that fixations during early viewing were shorter (È215 ms) than those during later viewing (È310 ms). Saccade amplitude has also been shown to change during viewing, with amplitudes decreasing as viewing time increases, and to stabilize during later viewing (Antes, 1974;Castelhano et al, 2009;Pannasch et al, 2008;Unema et al, 2005). Thus, there appears to be a tendency for short fixations and large saccades to characterize early viewing and for long fixations and small saccades to characterize later viewing.…”

“…Although some have reported little to no change in fixations as viewing time increases (De Graef, Christiaens, & d'Ydewalle, 1990), several studies have noted a tendency for fixations to increase during initial viewing periods and to stabilize during later viewing (e.g., Antes, 1974;Friedman & Liebelt, 1981;Pannasch, Helmert, Roth, Herbold, & Walter, 2008;Unema, Pannasch, Joos, & Velichkovsky, 2005). Castelhano et al (2009), for example, analyzed the duration of the first five fixations following scene onset for their search and memory tasks and found for both tasks that fixation durations increased as viewing time increased and then remained stable during later viewing (after È2 s).…”

“…According to the two visual systems hypothesis, the relationship between fixation durations and saccade amplitudes over time is systematic and indicative of two qualitatively distinct modes of scanning: global and local scanning (Frost & Poppel, 1976;Pannasch et al, 2008;Pannasch & Velichkovsky, 2009;Unema et al, 2005;Velichkovsky, Joos, Helmer, & Pannasch, 2005;Velichkovsky, Rothert, Kopf, Dornhoefer, & Joos, 2002;Velichkovsky et al, 2003). Accordingly, global processing can be seen as an orienting phase, during which shorter fixations and larger amplitudes dominate, presumably to capture the gist of a scene and establish regions of interest.…”

“…Local processing, on the other hand, is associated with longer fixations and shorter amplitudes, reflecting a more in-depth and objectcentered analysis. It has been argued that global scanning is restricted to early viewing (about the first 2 s following scene onset), after which local scanning dominates (Pannasch et al, 2008;Unema et al, 2005;Velichkovsky et al, 2005). This pattern of change in fixations and saccades has been shown to be relatively stable over a variety of viewing conditions, including differences in cognitive demand (Pannasch et al, 2008;Unema et al, 2005), as well as differences in the affective state of individuals and scenes (Pannasch et al, 2008).…”

Introducing context-dependent and spatially-variant viewing biases in saccadic models

“…Small sac-55 cades would reflect a focal processing of the scene whereas large saccades would be used to get contextual information. The latter mechanism is associated to ambient processing (Follet et al, 2011;Unema et al, 2005). A second bias concerns the distribution of saccade orientations.…”