This experiment tested alternative explanations of list method directed forgetting effects. Two word lists were studied by 135 subjects. Between lists, subjects were instructed to remember both lists , remember both lists as well as in which list words were studied , or to forget the first list and remember the second . All subjects took both recall and recognition tests with test order varied between subjects. Among subjects who took the recall test first, the forget group showed a directed (...) forgetting effect with both recall accuracy, recall typing time, and recognition reaction time measures. Contextual segregation of List 1 words by forget subjects was ruled out as a sufficient cause of the effect. Limited support was obtained for a differential rehearsal explanation of the effect. Within-group comparisons and findings of release from directed forgetting support inhibitory processes as the major cause of the directed forgetting effect. (shrink)

Directed forgetting is a successful method for thought control whereas thought suppression is notoriously ineffective. We tested a specific hypothesis about what difference between the two paradigms causes the difference in outcomes. Both paradigms instruct participants to suppress certain thoughts, but in thought suppression experiments participants are also told to report intrusions of unwanted thoughts. We added a condition to the typical directed forgetting experiment that instructed participants to report intrusions. When participants tried to forget a word list but also (...) reported intrusions, forgetting did not occur. The results are important for understanding control of conscious contents and have implications for practicable applications of individual thought control. (shrink)