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Object recognition in natural scenes occurs extremely rapidly, suggesting that it requires only feed-forward processing (Serre et al., 2007). However, recurrent processing is involved in many operations that are relevant for object recognition, such as perceptual grouping and figure-ground segmentation (Lamme, 1995; Roelfsema et al., 2000), and disruption of feedback impairs object recognition performance (Koivisto et al., 2011). Interestingly, the effects of feedback disruption are strongest when the object is ‘less easily segregated’from the background (as assessed by post-hoc ratings; Koivisto et al., 2013). This suggests that the degree of feedback may depend on overall scene complexity. Here, we tested this hypothesis by manipulating scene complexity based on two global image statistics: contrast energy (CE) and spatial coherence (SC). These statistics respectively summarize local edge intensity and higher …