Tuesday, June 11, 2013
Working Memory Executive Control
Do you consciously monitor your working memory? That’s the limited-capacity memory you use when looking up a phone number, for example. If you fail to keep the numbers actively in mind while dialing, you may have to look up the number again. In other words, do you check yourself to see if you are still paying attention to what is in your working memory? Is your mind wandering away from what you are trying to hold in working memory? The cure is to deploy your brain’s innate capacity for executive control over working memory.
For more complicated memory chores than dialing a phone number, are you consciously aware of updating what is in your working memory at a given moment with new information? Do you think about being able to recall information you have just received—as when you are reading? Or do you ever willfully suppress what is in your working memory—as for example, expunging an unpleasant thought.
These questions deal with how well you are consciously aware of the likelihood you can recall what you are experiencing. I suspect that most of us exert some conscious executive control over working memory, but not nearly as efficiently as we could or should. Does it matter? Well yes, because controlling what is in your working memory affects the ongoing thought processes that are using the information that is in working memory. Moreover, how well you monitor your working memory affects how well the information registers in your brain and how well it can become consolidated into a more lasting memory.
I explain the consolidation process and ways to enhance it in my book, Memory Power 101.
Executive control of memory is relatively new in memory research, but one group reports studies suggesting that such research will prove fruitful. A year or so ago, this group’s poster presentation at the Society of Neuroscience meeting intrigued me, and I am delighted that the work has now been formally published.
One of their experiments evaluated listeners’ ability to monitor their moment-to-moment working memory storage capacity as new information arrived. As they listened to recorded word lists, experimenters told the subjects to pause the input at the maximum point that would still allow them for perfect real-time memory recall. That is, they pressed a key to pause the input of words in the list at the latest point at which they believe they would have perfect recall. Interestingly, all subjects paused the recording consistent with their known working memory span, as had been determined in pre-experiment testing. In a follow-up experiment, experimenters reduced the sound volume of the word list so that more effort had to be exerted to perform the task. Under these conditions, subjects were much less accurate in matching their listening to their natural working memory capacity and thus their learning was not optimal.
Obviously, such results suggest that making tasks more difficult can degrade thinking and learning. Teachers and professors who speak softly or with foreign accents should take note. Whatever benefit accrues from the challenge to pay better attention under difficult situations is offset by limitations in working memory storage capacity. Examples of degrading influences in addition to sound volume in listening to information include:
Listening is made more difficult by:
· Extraneous noise
· Unfamiliar speech accents
· Speaking too rapidly
· Speaking too softly
· Simultaneous presence of visual stimuli that conflict or distract
· Irritating or distracting mannerisms of the speaker
Reading is made more difficult by:
· Font and page design selection
· Convoluted syntax, awkward sentence structure
· Unfamiliar vocabulary
· Distracting visuals
· Wordiness, poor grammar
· Poor reading technique (tracking with finger movements, random eye fixations, small fixation span (a few letters or one word at a time)
In all situations, an important factor is whether the listener or reader has control over the speed of information presentation. Thinking and learning are compromised if a person has no control over chunking of information input and matching the input to their working memory storage capacity.
Another factor, not considered in this study, is the likelihood that people differ significantly in conscious executive control capability. We know, for example, that some people can hold focus much better than others can, and this certainly affects their ability to optimize working memory storage of information input.
Can working memory executive control be trained? There are already effective training protocols for expanding working memory capacity (as in the number of items you can hold in working memory). I suspect that we will soon see training programs to enhance executive control of working memory.
To summarize, you can optimize thinking and learning by willfully controlling the ease and convenience of information input as well as by how well you have developed a habit of conscious executive control.
Amichetti, N. M., Stanley, R. S., White, A. G., and Wingfield, A. (2013). Monitoring the capacity of working memory: executive control and effects of listing effort. Mem. Cogn. DOI: 10.3758/s113421-013-0302=0