People have noted often that we are conscious of our memory recall from episodic and semantic memory and also of imaginings. That is what it means to recall or to imagine – to be aware of the memory or the imagining. It is as if conscious awareness was a structure into which our awareness of ‘now’ or of some memory of past time or even some imagining of future or fictitious time, can be housed. It has been likened to a work space, a theatre, a model world – for now I am going to call it the conscious awareness structure. It is a 3D space centered on ‘here’, ‘now’ and ‘I’ but with the ‘here’, ‘now’ and occasionally the ‘I’ being ‘virtual’ when dealing with recalled memories or imaginings. We seem to be able to tell the difference between our awareness of the three different sources of the experience. It is not that the mechanics of recall or imagining are conscious but that the awareness of the result is in our conscious experience. I suspect that the same structure is used to house dreams.

It may be (and appears to me likely) that the process of recall is not a simple one. When I try to remember events from long ago, I find that they now incorporate changes or additions that make them fit with my current view of the world. I remember the pinkness of a particular dawn and it is placed in a particular farm yard. It is a familiar image from being recalled many times. Then I run across a photograph of the yard in question and I am surprised that my memory is physically impossible – there is no place in that yard to see the perspective I remember. Now when I recall the dawn it is seen corrected from its previous deviation. When we recall, we must fit the memory into our current conscious awareness structure. Throughout our lives, our bank of memories is reworked, consolidated, updated and so on to keep the bank useful and consistent. Some may think this is a poor way to arranged things. It would be better if evolution had produced an indelible, accurate trace of our past. But the purpose of our memories is not accuracy or permanence; it is usefulness because memory gives the elements used to think, solve problems, learn, plan the future, invent, avoid disaster. If I buy a new stove, I still want to use the lessons I learned on my old stove, not re-learn cooking with each change in my kitchen. Old memories have to be made to fit in the current structure of our awareness or they become useless. Little and large bits of memory are part of the stuff of thought.

We may (and again it appears to me likely) use fragments of memory to create imaginings. Stripped of their reference to a particular event, fragments can be furnish the pieces of an image – a tree here and a park bench there. Tulving’s notions of mental time travel and the possible connection of amnesia and inability to imagine are pointers to this sort of use of memory for imagining. These fragments used to form imaginings do not effect the original memory though, because the context of the original memory has to be part of the reworking that can occur with memory recall.

How important is the link between memory and consciousness? David Chalmers postulates the idea of a type of zombie that is indistinguishable from a conscious person but lacks consciousness. He says because we can envisage such zombies, they must be logically possible and therefore….well, many things follow. But it does not seem to me that his idea of zombies can be envisaged. People without consciousness would be very distinguishable from those without. A person without consciousness is likely to have no memory or a very poor one and no imagination or a very poor one. They would be very poor learners and speakers. The fluid easy flow of elements between consciousness and memory is extremely important to how the brain works. The conscious awareness structure is a very important component of the brain. It is well worth its cost in biological terms.

In the next post in the series, I am going to leave the memory connection and deal with other possible functions of consciousness. The reason for examining memory first is that I think it is neglected in discussions of consciousness.

There is more to come. Previous posts in this series:

Possible functions of consciousness 1 - leading edge of memory

Possible functions of consciousness 2 – gate to meaning

Possible functions of consciousness 3 – working memory