Introduction
Cognitive Psychology has studied imagery since the mid-nineteenth century. Since that time there are over 45,000 documented studies concerning images and imagery in the psychological genre alone. (Roeckelein, 2004, p. ix) Still, there is no definitive proof that images, that is visual representation, actually exist in the brain at all. Block (1981) found far too many problems with definitions to answer this one. “One side, the pictorialist side…agrees that we don’t literally have pictures in our brains, but…nevertheless that our mental images represent in roughly the way that pictures represent. On the other side, the descriptionalist side…thinks of mental images as represented in the manner of some non-imagistic representations—namely, in the manner of language rather than pictures.” (Block 1981) Nor is there any definitive proof that explains exactly how what we see, perceive or think is represented in the brain. In fact, nobody really knows how anything is either represented in the brain or stored in memory. Considering the immense number of people who are blind from birth or those who have little or no visual memory, it seems a bit illogical to assume that mental imagery is of prime importance, especially considering that there are many brilliant people among those who have no sight or visual memory.
Definitions
Roeckelein’s book (2004) was invaluable as a reference for this project. He included several astute definitions of images and imagery:
- When it comes to so-called mental images, the relevance of the word image is distinctly controversial and although it would be perverse to deny the existence of visual “imaginings” there are those who insist that it is misleading to describe what is “seen” as a visual image. — J. Miller, 1990
- Researchers have conceptualized mental imagery in different ways: as a phenomenal experience, as an internal representation, as a stimulus attribute, and as a cognitive strategy. — J.T.E. Richardson, 1999
Webster’s Third New International Dictionary (1993) defines the term image as a noun (Middle English from Old French, short for imagene, from Latin imagin-, imago; akin to Latin imitari to imitate) as “a reproduction of a person or thing…a thing actually or seemingly reproducing another…exact likeness…a tangible or visible representation…a mental picture”; and as a verb as “to describe or portray in language especially in an effective or vivid manner…to call up a mental picture of…reflect, mirror…to create a representation of.” (Roeckelein, 2004, p. 2)
Discussion
So it seems that we are woefully lacking in a universal definition for image or imagery. It would seem then impossible to prove that images or imagery have anything at all to do with mental representation. However, there is a light at the end of the tunnel or rather in the interior of the brain. See the particular area of study called “diagnostic imaging” or “images of the brain in action” in Gregory (1987, pp. 347-53); this technological field includes concepts and devices such as X-ray computer tomography (CT), positron emission tomography (PET), and nuclear magnetic resonance (NMR) or magnetic resonance imaging (MRI). This technical-laboratory approach to the topic of images permits researchers to study the production of refined anatomical images in vivo and to consider images as measured in terms of local chemistry, metabolism (i.e., the use of oxygen and glucose), and blood flow within the brain. (Roeckelein, 2004, p. 4)
What this means is that there is, indeed, some kind of imaging going on inside the brain, if we define an image as a reproducible representation. We can do this, because of vector graphics and computing power. Vector graphics are mathematical formulae that represent actual graphics, replacing raster graphics, which use bitmaps or patterns of dots to represent the graphic. (SearchWinDevelopment.com 2009) Logically, it is easier to store formula for creating a shape than to store a bitmap representation of that shape. So if we can dream up this kind of system for computer processing, it stands to reason that there might be something similar or vastly superior used in the human brain. The human brain is actually woefully slow in processing information as compared with a nice fast computer, but some other attribute of the brain makes it vastly superior to all the computers in the world running in parallel.
The role of imagery in information processing took a leap forward when researchers began to think about how one could program a computer to produce specific types of behavior. To program a computer to mimic imagery, one must specify an image representation with particular properties. ( Kosslyn 1994)
Investigation of the Possibilities
In a discussion with a friend who has taught in Asia, we began to discuss the basis of languages, and how people think. Now, thinking, as we define it, probably cannot take place without language, a system of symbols to represent everything. However, even deaf people use language. It is simply not oral. There is another difference between westerners and Asians, the meaning of the language is contained within the sound in phonemic languages, while the meaning in pictorial languages is contained in the writing. In English, the writing is a representation or symbol of the sound, while in Chinese, the sound is a representation or symbol of the writing. So do Asians think in sound? Do all native speakers of a phonemic linguistic group think in sound? This has not been studied as far as I can determine with my research. However, either sound or writing could be defined as an image by the definition contained in the paragraph discussing vector graphics.
Katz (2000, p. 187) discusses mental imagery in an encyclopedic style entry, and defines imagery as “the mental construction of an experience that at least in some respects resembles the experience of perceiving an object or an event, either with or without direct sensory stimulation.” Mitchell and Ziegler (2007) showed that imagery does figure in the development of children and especially Ziegler developed theories concerning imagery in children’s books and their value to learning and development. However, none of his work actually proved that images exist inside the brain, only that they aid learning acquisition.
Sperling (1960), posits that the most convincing experiments on the properties of imagery have usually been visual, though the stimuli might have been presented orally, and the participants may be able to recall a symbolic visual representation for commonly represented items (e.g., hearing a letter of the alphabet). But this again only proves that we translate the representations in the brain into visual symbols or auditory symbols when we speak.
So it is clear that most studies fall short of proving the existence of a visual representation, or image, in the brain. However, the aforementioned electronic magnetic imaging systems have shown that there is certainly something going on in that portion of the brain which has been identified as controlling visual function. “…we have shown that SOBI was able to separate visual components that clearly correspond to neuronal responses from early and later visual processing stages that are correlated because of common input” (Tang et al., 2000a, 2000b). (Tang & Pearlmutter, 2003, p. 196) Because there is a response within the area defined as the visual cortex when stimulus resulted in a visual impression, we know there is a connection. However, the fractal geometric mathematical representation used to download graphic satellite images bears no resemblance to the actual images which are decoded on the earth.
One recent development actually provides proof that there is some kind of visual mapping in the brain, the vOIce (2009) Bob Macdonald (2009) tells us about a woman who has been blind for 25 years, yet can now see with the aid of a small webcam and a processor which decodes the image into sound. Her brain perceives the sound patterns as an image because it recognizes the patterns. This was thought not to be possible with people who were born blind, but research is actually showing some positive results. Images have a pattern that is distinct from the sound. That pattern can be decoded by the human brain as an image.
Conclusions
So the vOIce proves the existence of images in the brain by inference. If the images did not exist, the vOIce would not work at all. Pat Fletcher knows what an image is, and she is experiencing images with no sight. Others who have been blind from birth also are experiencing something as an image that allows them to perceive physical attributes without touching the target objects. They can learn to navigate just as a sighted person does. This really does not tell us what they perceive within their brains, whether or not there is an image, due to the logistical problems of occupying two brains at once. However, there is a symbolic representation, which is translated to something equivalent to sight.
Is there a real image in the brain: probably not. We call up our memory of an image with the correct stimulus, and we translate whatever is in the brain to either visual or auditory representation. However, nobody has been able to prove the existence of imagery in the brain. Even the MRI only proves that the area of the brain which controls sight is excited by stimuli that incite images to become active whenever a visual symbol is perceived, whether in reality or in the description. There is some symbolic code there which we perceive as an image and act upon it. From the advances in computer science, it seems logical to assume that some much more sophisticated symbol for storage medium is used in the human brain.
References
Block, N. (Ed.) (1981). Imagery. Cambridge, MA: M.I.T. Press.
Eysenck, M. and Keane, M.T. (1995) Cognitive psychology: A student’s handbook, Erlbaum, Hove Katz, A. (2000). Mental imagery. In A.E. Kazdin (Ed.), Encyclopedia of psychology. Vol. 5. New York: Oxford University Press.
Kosslyn, S.M. (1994). Image and brain: The resolution of the imagery debate. Cambridge, MA: M.I.T. Press.
Macdonald, Bob, Quirks and Quarks. (2009). Web.
Quirks and Quarks, CBC Radio on line. Web.
Metzler, J., & Shepard, R.N. (1974). Transformational studies of the internal representation of three-dimensional objects. In R. Solso (Ed.), Theories in cognitive psychology: The Loyola Symposium. Potomac, MD: Erlbaum.
Mitchell, P & Ziegler, F, Fundamentals of Development, 2007
SearchWinDevelopment.com 2009, What is Vector Graphics? (2009). Web.
Sperling G. ( 1960). “The information available in brief visual presentations”. Psychological Monographs, 74, 11 (Whole No. 498).
The vOIce, Seeing with Sound, Technology for the Totally Blind. (2009). Web.