Abstract:Instructing people to forget a list of items often leads to better recall of subsequently studied lists (known as the benefits of directed forgetting). The authors have proposed that changes in study strategy are a central cause of the benefits (L. Sahakyan & P. F. Delaney, 2003). The authors address 2 results from the literature that are inconsistent with their strategy-based explanation: (a) the presence of benefits under incidental learning conditions and (b) the absence of benefits in recognition testing. Experiment 1 showed that incidental learning attenuated the benefits compared with intentional learning, as expected if a change of study strategy causes the benefits. Experiment 2 demonstrated benefits using recognition testing, albeit only when longer lists were used. Memory for source in directed forgetting was also explored using multinomial modeling. Results are discussed in terms of a 2-factor account of directed forgetting. Key words: directed forgetting, intentional forgetting, study strategies, multinomial modeling, inhibition
Article:When people find out that they are talking to a memory specialist, they often ask about how to improve their memories and how to remember more effectively. The irony of this is that people should perhaps be interested in how to forget things better in order to improve memory, as it appears that forgetting often leads to better memory (R. A. Bjork, 1989).One way to study the linkage between forgetting and learning is to ask people to forget something they have just studied-a procedure known as directed forgetting. A forget instruction can be delivered either after each item (known as the item method) or after a block of items (known as the list method). These two methodologies were shown to have different underlying mechanisms, with the item method reflecting encoding phenomena (better encoding of forget vs. remember items), and the list method most likely reflecting retrieval phenomena (e.g., Basden, Basden, & Gargano, 1993;R. A. Bjork, 1989). The current article focuses on the list method of directed forgetting because the mechanism underlying this phenomenon has created a variety of theoretical viewpoints as opposed to the mechanism supporting the item method. (For a more complete review of directed forgetting and related procedures such as specific intentional forgetting, see H. Johnson, 1994, or MacLeod, 1998 A typical list method directed forgetting study presents participants with two word lists to study. Between administration of the two lists, the experimenter instructs half of the participants to forget the first list and the We are grateful to Xiangen Hu and William Batchelder for their help with the GPT.EXE software and multinomial models in general. Thanks also go to Kathryn Hughes, Kristin Kukharenko, Ryan Lobo, and Isabel Manzano for their help in data collection and scoring.