​In a speech delivered in Las Vegas this past week, Secretary of Education John King started a brief speaking tour on a subject that appears will be one of his priorities, at least in the near term: the need to broaden school curricula.
 
The speech made many points with which educators already agree. No Child Left Behind narrowed the curriculum, as educators, concerned about standardized test scores, engaged in heavy doses of test prep. King likely knows (but figured it would not help his case to point out) that NCLB might have narrowed the curriculum further, but it was damn narrow in the late 90’s, before NCLB came on the scene (see here, here and here).
 
King offered other powerful arguments in favor of a broader curriculum, again ones that are familiar to educators: if offers a better chance for a child to find the subject that really excites them, and breadth in knowledge better comports with what we consider a real education.
 
And King pointed out that knowledge feeds academic excellence, a point I’ve harped on tirelessly (and likely, tiresomely) for years. He also tied this theme to educational justice, a point ED Hirsch has emphasized: if knowledge is the key to academic (and eventual economic) success, bear in mind that schools are the best (and probably only) hope for exposure to this knowledge for children whose access to it is limited at home.
 
The reasons behind this linkage between knowledge and successful thinking can get technical pretty quickly. I’ve written about them elsewhere  by describing experiments showing the linkage, along with some version of the cognitive theory underlying it.
 
In this blog I want to take a different turn and discuss mental representations and metaphors for thinking.
 
One of the problems in persuading people that knowledge matters to thought lies in how they think these two. They often think of them as separate: people have something like a database of stuff they know, and then they have mental processes that do the thinking. You plug the knowledge into the thinking processes. This view leads naturally to the conclusion that knowledge isn’t all that important, because you can get knowledge from the environment—by looking things up, for example.
 
Oftentimes, when I describe experiments showing that thinking processes don’t work very well in the absence of knowledge, people will respond by saying “right, I totally agree. You need something to think about.” But that’s still not really it, because it’s just another way of saying you need the knowledge database—knowledge is still separate.
 
To the extent that those of us arguing for the importance of knowledge have invoked cognitive theory, we have not done ourselves a favor by using the metaphors we have. Metaphors are enormously helpful in understand new ideas, but they can also lead you astray. That’s because the analogous situation won’t share all of the features of the new thing you’re describing. Likening atoms to our solar system leads to trouble if kids make the natural extension, thinking that electrons travel in elliptical orbits.
 
The stripped-down model of the cognitive system I’ve used is shown below.
This metaphor is really good for understanding the limitation of working memory, and that’s important. But this metaphor of the mind looks very consistent with the idea that you have a data bank of information (long term memory) and a place you think with it (working memory).
 
This is a cartoon version of one family of theories of memory, but it’s not the only one. There’s another that’s less intuitive, but that is growing in its acceptance and that does not naturally lead to the erroneous separation of knowledge & processes.
 
In the model shown above (the best known version of which is Alan Baddeley’s), working memory is likened to a place, and in order to use a long term memory representation the mind creates a copy of the representation and puts it into working memory.
 
In the other family of models (e.g., by Nelson Cowan, or Randy Engel), working memory is not a place, but a state. Long term representations can participate in different cognitive activities, some of which put that representation in a state we’d call being in working memory (e.g., associated with consciousness).
 
Another important feature that is not a part of all theories, but is growing in acceptance is that idea that all cognitive systems have memory in them. Consider your visual system. You prepare to cross a busy street—you look left, then right, then left again. In so doing you are getting a series of snapshots of the scene on each side of you, a scene that looks a little different with each view. But you don’t perceive it as different scenes. Your ability integrate these snapshot into a consistent scene requires memory at a very short scale (a second or so).
 
But your visual system also uses memory at a much longer scale. When you walk into a grocery store, you have expectations about what you’re going to see, and those expectations influence what you actually do see. These expectations are built from experiences over the course of months.
 
This view of memory being embedded in all cognitive systems was explicit in my own theory of motor skill acquisition.
 
Once you think of all cognitive systems as having memory at different time scales , there’s not much reason to think of STM and LTM as different; rather, they are different states of the same memories. Gus Craik has made this point for many years.
 
If this is hard to wrap your mind around, here’s an alternative metaphor for you. Don’t think of memory as a databank where you store things. Think of a hill of sand—that’s your mind. You pour water on it—water is thought. The water coursing over the sand creates gullies and rivulets. That’s memory. It’s a representation of where the water (thought) has been in the past and if the water moves through those same channels they will become a little deeper. The next time you think (pour water) it will likely happen in the channels it’s followed before….but not necessarily.  The new water also has the potential to change the gullies on the hill.
 
This metaphor captures the idea that the difference between long term memory and short term memory is one of state. Long term memory is a gully. Short term memory is a gully with water in it (i.e., that is guiding thought).
 
I started this blog by saying that John King’s efforts to broaden curricula are multi-faceted, and research showing the importance of knowledge to academic skills is just part of those efforts. Then too, people’s pre-existing beliefs about knowledge and cognition are just a part of that one facet, and metaphor is just a part of pre-existing beliefs. So this metaphor business is a small point, but it may have outsize consequences for how people think about knowledge and thinking skill.
 
Spread the word.