I've been looking at the original article in Nature (Anderson & Green, 2001; thanks, David!). The authors themselves don't seem to worry about the distinction between suppression and repression. They use suppression in their title, for example, but lead off their paper by discussing Freud and repression. The critical point seems to be that either term implies that the process is an active one, as opposed to mere forgetting. And that's where I think the parallel to Freud's repression is the weakest. They don't provide any evidence that the demonstrated lack of knowledge of what was previously learned is still lurking at some deeper level, only inaccessible to the subjects. All they show is that the subjects no longer seem to have the information, and that's not necessarily repression. Perhaps they need to use something like the method of savings to show that the information is retained, despite the subjects' verbalizations to the contrary. Relating your findings on the topic of learning nonsense pairs to Freud is always a good way to attract attention. But Freud himself wouldn't have been impressed. A hapless American named Saul Rosenzweig got there before Anerson & Green, publishing an experiment supposedly demonstrating repression back in 1934. He wrote an excited letter to Freud about it. Freud was underwhelmed, and essentially told him to bug off. In his reply, Freud said he didn't need experimental evidence, he _knew_. I expect he would say the same thing to Anderson & Green. Nevertheless, it's an interesting phenomenon, and A & G have done a good job in considering alternative hypotheses and shooting them down. The basic finding, as I understand it, is that if you learn a set of paired associates, and then practice _not_ remembering, later you find that you _can't_ remember. For me (and, I think, for them), the critical comparison is between 0 repetitions of practicing forgetting and 16. They show a difference (reading off a very tiny graph) of something like 10% less remembering for the 16 repetitions group, which is hardly a robust phenomenon (and certainly much, much less than the kind of classic repression supposedly underlying much human dysfunction). However, even that finding is open to other interpretations, such as extinction or interference. So their even more critical comparison is with another group, which received a different cue than the original paired associate, but one which would normally suggest the word in question (e.g. if the target word was "roach", the hint was "insect r__"). They still get an effect, which suggests that the information is now gone or (sigh!), perhaps repressed. But the effect is weaker still, something like only a 3-5% difference in recall. This is where I get sceptical. There were 32 subjects, which is a healthy-sized group. But they provide minimal information about their statistics, don't tell us whether one-tailed or two (I'd object to one-tail, as I almost always do), and give no indication of variability (SEs, for example). So is a 3-5% difference enough on which to hang the claim of proof of repression? I think I'll reserve judgement. (One other thing I'd like to see is more examination of the exact manoeuver that led to the effect. Their even more critical comparison is between a group that tried to forget 16 times, compared with trying to forget 0 times, and tested with a different hint on testing (independent probe condition). Instead of zero trials of trying to forget, perhaps those subjects could get 16 trials of something else, say thinking about what they're going to have for supper. If 16 trials of thinking about supper produces less "repression" than 16 trials of trying to forget, that would be interesting.) -Stephen Anderson, M., & Green, C. (2001). Suppressing unwanted memories by executive control. Nature, 410, 366- ------------------------------------------------------------------------ Stephen Black, Ph.D. tel: (819) 822-9600 ext 2470 Department of Psychology fax: (819) 822-9661 Bishop's University e-mail: [EMAIL PROTECTED] Lennoxville, QC J1M 1Z7 Canada Department web page at http://www.ubishops.ca/ccc/div/soc/psy Check out TIPS listserv for teachers of psychology at: http://www.frostburg.edu/dept/psyc/southerly/tips/ ------------------------------------------------------------------------
