Dallett, K., Wilcox, S. G. & D'Andrea, L. (1968). Picture memory experiments. Journal of Experimental Psychology, 76(2), 312-320.

Ss were shown a series of pictures, and were tested with another series in which 1/2 the original pictures appeared unchanges, while 1/2 were replaced by similar pictures. In Experiments I and II, giving the title of the picture and requesting recall before recognition testing made no difference in recognition accuracy. Both immediate and 1-wk. retention intervals were used. In Experiments III, IV, and V, the pictures were presented in degraded form in the original presentation, in the test, in both, or in neither. Degradation consisted of blurring the focus in Experiment III, whil inversion was used in Experiments IV and V. Experiments III and IV involved immediate testing, while in Experiment V selected conditions were tested after 48-hr. and 1-wk. intervals. Both forms of degradation lowered recognition accuracy. Degradation in both presentation and test was less damaging to accuracy than degradation in 1 phase alone. If the pictures were degraded in only 1 phase of the experiment, it did not matter which it was. This suggests that it is no more difficult to remember degraded pictorial information than it is to remember undegraded information.