Yes, it was harder for me to detect a change in the picture when it flickered because it was harder for me to maintain focus on the change I was supposed to be looking for. My data does support my evaluation since the proportion correct with the flicker was 63% and the no flicker the proportion correct was 100%. The flicker condition is the appearance of a blank gray box or a mask in between pictures presented. The blank image swamps the local-motion signal that would typically be caused by a change but our attention is not affected by it, the mask prevents automatic detection of change. Change is detected by slower, higher-level process by searching the scene thoroughly until you find the changed object. In the no flicker condition the type of search strategy commonly used is the search for the local-motion signal caused by change of object.
With this type of strategy it is easy to detect change when it is occurring and when there is also no change. In the flicker condition the commonly used strategy is searching the scene, object by object until the change in object is found. Advanced Question The reaction time reported is to show how long that it took to identify the change in object per photo. Difficulty between the conditions can be observed and examined by recording the reaction time of the experiment. Flicker conditions are the same as the driving conditions stated above. Looking away from the road to look at something else is the same as seeing a scene then looking at a blank field followed by a different scene. You may not be able to notice the change right away due to response time and you might hit someone or another vehicle because of the change of scene.