Friday, March 11, 2011
Brain Training and Delay Discounting
I encountered Bickel et al.'s article Remember the Future: Working Memory Training Decreases Delay Discounting Among Stimulant Addicts through another research blogger. It's way outside my area of expertise, but as someone who struggles with excessive delay discounting myself, I found it extremely interesting, so I hope any psychology experts reading this will forgive me for posting my musings on the article.
Delay discounting is essentially the degree to which we consider rewards less valuable (or penalties less threatening) if they come later rather than now. It's something we all do to some degree or another, and it's not in principle completely illogical. After all, a delayed reward may never actually come, or may come after we no longer need it, while a delayed penalty may be avoided or may come after we have put ourselves in a position to better withstand it. The problem occurs when we discount future rewards and penalties to the point of being unable to maintain effective long-term resolve to address important life challenges.
In my case, excessive delay discounting manifests primarily as extreme procrastination on lengthy projects. Reading a book or playing a video game or taking a nap or cleaning my kitchen or making something good for dinner requires only a small amount of effort and gives me a little bit of a reward now. On the other hand, while working on a long-term project now may in the end help ensure a much larger reward, that reward (or the avoidance of any penalty for failing to complete the project) is waaaaay in the future, and also waaaaay on the other side of a big ol' pile of work. It's all too easy to value the short-term, easy-to-get reward over the long-term, difficult one.
Bickel et al.'s paper describes a study conducted on people who show a different type of delay discounting, related to stimulant abuse. The notion is that drug abusers and other people who engage in addictive behaviors tend to value the pleasure gained now from their addictive focus more than they fear the various negative life impacts which they know their addiction will cause later. The researchers cite other work which suggests that delay discounting is indeed associated with various types of addictions.
This was what I would consider a fairly small study, enrolling only 27 participants. The participants were assessed in advance with what I can only assume was a somewhat standard measure of delay discounting (a number derived from certain test results via a rather strange-looking formula that I don't entirely understand). 14 participants (the "active training" group) then completed a certain number of sessions of training with commercially available memory training programs, after which their propensity for delay discounting was again assessed. The other 13 participants were matched to the active training participants based on gender and initial memory score. These participants formed the "control training" group. They completed the same memory training programs as the active training group, but in each case the answers were provided to them, so that these participants merely parroted the information that was right in front of them rather than having to remember anything for any significant length of time. The active training participants were rewarded for better performance, while the control training participants each received the same reward and followed the same progression through training modules as one of the active training participants. The number of training sessions varied pretty widely amongst the participants, from as few as 4 to as many as 15, and the training sessions were spread across 9–44 days.
The researchers claim that the active training group demonstrated overall a significant improvement (decrease) in delay discounting, while the control training group actually had a (non-statistically significant) increase in delay discounting. They also state that their analysis indicates that the active training group's improvement was indeed due to the memory training, and that various other relevant cognitive parameters do not appear to have been significantly impacted.
The small number of participants and the wide variation in training schedules means I'd want to see a lot more validation before relying too heavily on these results. However, analyzing the researchers' statistics, or the quality of their participant matching, or anything like that is rather beyond my expertise. I can at least say that nothing about their research is so obviously bogus that even I can detect it, and it seems like they've made a reasonable attempt to correct for countervailing factors.
The interesting possibility this research raises for me is that perhaps some of the elements of the recent "brain training" fad might actually serve some purpose. Despite the extravagant claims of those who peddle it, most of what I've heard about brain training has been fairly negative — no statistically significant improvements in any relevant aspects of overall cognition, and no real evidence that "brain training" helps you get any better at anything other than doing brain training. Could it actually be worthwhile for dumbass procrastinators like me to spend a few minutes every day on working memory exercises? This research certainly doesn't answer the question yet, but, like so many of these preliminary studies, it's a tantalizing pointer to a potentially valuable idea (which may or may not ever actually pan out).
Of course, for a procrastinator like me, "doing my memory training" might turn into just another cheap and easy way to put off the hard stuff for another few minutes. So maybe it's not such a great idea after all.
Bickel, W., Yi, R., Landes, R., Hill, P., & Baxter, C. (2011). Remember the Future: Working Memory Training Decreases Delay Discounting Among Stimulant Addicts Biological Psychiatry, 69 (3), 260-265 DOI: 10.1016/j.biopsych.2010.08.017