Suppressing unwanted memories: where there is a will, there is a way?

Research suggests that suppressing unwanted thoughts, generally, is an ineffective thought control strategy, because suppression attempts oftentimes fail, and, furthermore, result in a paradoxical increase of unwanted thoughts, later on. The present study sought to investigate whether manipulated expectations about suppression efficacy determine actual effects of suppression attempts. To test this hypothesis, participants listened to an audiotaped story, and were subsequently appointed to one of four conditions: a no-instruction-control (n = 20), suppression (n = 20), suppression-works (n = 20; participants were told that suppression generally is a fruitful strategy), or suppression-does-not-work (n = 25; participants were told that suppression primarily has paradoxical effects) condition. Two hours later, participants' memories of the story were tested, and several metamemory questions were answered. Induced expectations actually determined the perceived efficacy of suppression attempts, as well as thought frequency, although perceived or actual accuracy of recollections was not affected by the instructions.