Every now and then the issue of mental
images takes me in. In general it is an understudied and underdetermined conceptual schema. I get the feeling that it is just terminological and conceptual
confusion.
I will grant that it is one's own mental image, but we can still ask
certain questions that clear the air. Here are the pointed questions that takes care of some confusion, but they are often not asked or
illucidated within such discussions:
- Are your conjured mental images as robust as real life images? If you create a mental image of an apple, is it as detailed and vivid as looking at an apple on the table? (I find most people deny this when pressed.)
- What is the relationship between dream images and mental images? Are your consciously created mental images as strong as dream images?
- Do your dream images seem as real as everyday real images?
I find in these discussions that people
who claim they have mental images usually leave it baldly stated
(“Yes, I have mental imagery”) and do not state what exactly they
are experiencing. Often, if such people are pressed, they will allow
that such images are not as vivid as dream images, or some people
will say they do not have dream images as vivid as everyday life.
My general taxonomy here encourages me
to say that all perception is mental imagery. When you look at an
apple on the table, you have a mental image of that apple as mediated
through sensory content. In a dream you (or I at least) have mental
images of an apple, seemingly the same as if you are looking at it in
real life. If in waking thought I try to create a mental image of an
apple, I create nothing that is like the real life image or dream
image of an apple.
I can accept that we need image-like or
representational talk for much of our brain processing (see Damasio, for instance). My concentrating on a virtual apple
allows me to do all sorts of things. It can instigate knowledge about apples, or
instigate sensations of hunger and other emotions. I accept that my
trying to image an apple is using and reproducing some underlying
processes of “apple representing,” that it is using some "image-like" process broadly speaking. There is certainly a street from past immediately perceived imagery, to memory, to present recalling of that past image. When I have a night-dream image of a face I saw today (a perceived image that I had earlier), the image structures in the night-dream is similar as the earlier perception because the “picture” structures are in my head, so to speak. When I close my eyes and try to imagine that face, I am tapping into those “picture” structures and therefore can remember features of such a face or object.
I also admit that there are (at least) two other classes of people. On one hand there are people who have significant processing deficiencies or significant
imagery deficiencies. There may be people who do not dream at all. Or there may be people who have significant perceptual and consciousness difficulties, such as blindsight.
On the other hand, there may be people who have really strong
hallucinations of non-existent phenomena. We should also say
that psychostimulants or other conditions create robust images in some unusual way.
But back to the idea that there is a
large percentage of people that have robust daydreamed mental imagery and another large
(but supposed minority) percentage of people who do not have these
mental images. The papers, the wikipedia pages, the Stanford
Encyclopedia, and blogs that I have read do not give me confidence
that this is anything more than two classes of people who are not
expressing their selves in useful and coinciding ways. I will fully
admit that fault may lie with me (and others who follow my
schematization). That is, it may be that my seeming “darkness” of
thought holds imagistic and representational processes that I access
when doing my best to think about my house, and that these processes
and thoughts may be worthy of the name image. I also agree
that in some conceptualized way we may need to refer to what is
happening in my brain as an image. That
is, there may be brain processes that are relaying information about object
structures. If daydreaming processes are giving information that is robust, such that
those processes provide rich detail (so that I know or can imagine
redecorating every wall of my house, and this provides further information), then it may be prudent to say
that almost all individuals, including my self, have mental imagery.
As it stands, if I try to image an
apple it is nothing like the vivid image of directly perceiving a
real apple, and it is nothing like the vivid image of dreaming of an apple. I question that most people's
phenomenology is that different from mine. It seems far more parsimonious to me that most people have rather similar experiences and instead we have had some stupid language and expression problem. If someone has a good
study or a good way of explaining what they experience in their
mental imagings, I am all ears.
(My latest perusing led me to Eric Schwitzgebel's account, which gels well with the issues I raised
above.)
