I have spoken before, here on the website and in my books, about the importance of setting specific goals and articulating your specific needs. Improving your memory is not a single task, because memory is not a single thing. And as I have discussed when talking about the benefits of ‘brain games’ and ‘brain training’, which are so popular now, there is only a little evidence that we can achieve general across-the-board improvement in our cognitive abilities. But we can improve specific skills, and we may be able to improve a range of skills by working on a more fundamental skill they all share.
The modularity of the brain is emphasized in a recent study that found the two factors now thought to be operating in working memory capacity are completely independent of each other. Working memory capacity has long been known to be strongly correlated with intelligence, but the recent discovery that people vary not only in the number of items they can hold in short-term memory but also in how clear and precise the items are, has changed our conception of working memory capacity.
Both are measures of information; the clarity (resolution) of the items in working memory essentially reflects how much information about each item the individual can hold. So should our measures of WMC somehow encapsulate both factors? Are they related? It would seem plausible that those who can hold more items might hold less information about each of them; that those who can only hold two or three items might hold far more information on each item.
But this new study finds no evidence for that. Apparently the two factors are completely independent. Moreover, the connection between WMC and intelligence seems only to apply to the number of items, not to their clarity.
Working memory is fundamental to our cognitive abilities — to memory, to comprehension, to learning, to reasoning. And yet even this very basic process (basic in the sense of ‘at the base of everything’, not in the sense of primitive!) is now seen to break down further, into two quite separate abilities. And while clarity may have nothing to do with intelligence, it assuredly has something to do with abilities such as visual imagery, search, discrimination.
It may be clarity is more important to you than number of items. It depends on what skills are important to you. And the skills that are important to you change as your life circumstances change. When you’re young, you want as broad a base of skills as possible, but as you age, you are better to become more selective.
Many people die with brains that show all the characteristics of Alzheimer’s, and yet they showed no signs of that in life. The reason is that they had sufficient ‘cognitive reserve’ —a brain sufficiently well and strongly connected — that they could afford (for long enough) the losses the disease created in their brain. This doesn’t mean they wouldn’t have eventually succumbed to the inevitable, of course, if they had lived longer. But a long enough delay can essentially mean the disease has been prevented.
One of the best ways to fight cognitive decline and dementia is to build your brain up in the skills and domains that are, and will be, important to you. And while this can, and should, involve practicing and learning better strategies for specific skills, it is also a good idea to work on more fundamental skills. Knowing which fundamental skills underlie the specific skills you’re interested in would enable you to direct your attention appropriately.
Thus it may be that while increasing the number of items you can hold in short-term memory might help you solve mathematical problems, remember phone numbers, or understand complex prose, trying to improve your ability to visualize objects clearly might help you remember people’s faces, or where you left your car, or use mnemonic strategies.