Thoughts on memory


First thoughts on memory

 

Thinking back to my lectures on the topic of memory, what has stuck in my mind is the fact that memory seems to be generally thought of as a modular system. It's divided into short and long term components, and I think that working memory is either a synonym for short-term memory (STM) or a sub-set of it. Perhaps it's referred to as working memory because it enables us to keep information in mind for long enough to carry out some sort of operation on it. Information comes in through our senses, vision, smell, touch etc, and, as per thoughts on the The Nicer (Neisser) Page, attention is probably brought to bear in order to select parts of this whole for further processing. So, in the short term we can apparently spontaneously recall small parts of a larger scene. Ok then, next it seems to me that in order to transfer something to long-term memory (LTM) we need to do something else to the stuff in the STM, like rehearse it or associate it with a spatial location (like when we were having our writing centre intensive training days - I could remember everybody's name by thinking where we were all sitting).

 

First of all, do I think that the modular account of memory is valid? Well, people with dementias often lose their STM while keeping their LTM until a very late stage. So it does seem to be modular. Whether or not this means that the two modules also occupy different regions in the brain I'm not sure. Although, dredging stuff up from my own LTM, I seem to remember that STM is somewhere in the frontal region. Gawd nose where LTM is!

 

Secondly, are there any dissenting voices? Dunno. This is something I must find out, because it would probably be quite interesting to write about.

 

Thirdly, how does the modular model stand up to formal experimental and imaging studies? And is there any evidence from computer modelling work? Dunno and dunno. Must find that out.

 

Fourthly, is working memory the same things as STM or is it a subset? Don't have the foggiest what the literature says, but once again I think of people with dementias. They may have an almost nonexistent STM, but are still often able to carry out everyday operations like conversing (albeit in a limited way), eating and going to the loo until quite a late stage in their illness. All of these things seem to me to require the ability to bring attention to bear on sensory information which might come from outside or inside the body (I have hunger pangs and must eat, my bladder feels full so I must wee). They can do this in the moment but can't remember that they did it two minutes ago. So maybe WM is neither the same nor a subset of STM but rather something else that intersects with it. Maybe it even straddles STM and LTM?

 

In conclusion, there does seem to be a STM module and a LTM module with information passing betweeen them. There also seems to be some kind of sensory, stimulus-driven gateway which leads into the STM module.

 

I'm remembering Baddeley and Hitch. Are they relevant? Must find out.