Rothkegel et al. 4 trial basis. The pre-trial fixation time primarily assures that the initial fixation is long enough to avoid a strong orienting response to the center of an image. Finally we compare our data to five different models of saccade generation in scene view- ing. An extended version of a recently published model of saccade generation (Engbert, Trukenbrod, Barthelm´ e, & Wichmann, 2015) with an additional initial central activation that decreases over time best explains the data in terms of maximum likelihood (Sch¨ utt et al., 2017) and qualitative progression of the CFB over time. In terms of maximum likelihood a model that imitates the visual attention span of humans combined with the empirical fixation map explains the data equally well but fails to reproduce the qualitative progression of the CFB over time. A set of 120 images was presented on a 20-inch CRT monitor (Mitsubishi Diamond Pro 2070: frame rate 120 Hz, resolution 1280 × 1024 pixels; Mitsubishi Electric Corporation, Tokyo, Japan) in Experiment 1, 2 and 4 and on a different 20-inch CRT monitor (Iiyama Vision Master Pro 514: frame rate 100 Hz, resolution 1280 × 1024 pixels; Iiyama, Nagano, Japan) in Experiment 3. The images were the same as in Tatler’s (2007) original study on the central fixation bias. Images were indoor scenes (40 images), outdoor scenes with man-made structures present (e.g., urban scenes; 40 images), and outdoor scenes with no man-made structures present (40 images). Images were taken using a Nikon D2 digital SLR using its highest resolution (4 megapixel). All pictures had a size of 1600 × 1200 pixels. For the presentation during the experiment, images were converted to a size of 1200 × 900 pixels and centered on a screen with gray borders extending 64 pixels to the top/bottom General Methods Stimuli