Object Detection Task Training and Test Stimuli. Examples of training (left) and test (right) stimuli are depicted. Images in the top row contain a target object, while those in the lower row do not. In this example, the target object is a small bomb hidden behind the boxes, as indicated by a dark patch.
Coffman et al. BMC Neuroscience 2012 13:108 doi:10.1186/1471-2202-13-108