We argue that the primary function of mental imagery is to allow us to ultimately give rise to the subjective experience of perception' (Kosslyn et al. .. () defined it as 'imitative representation of some event or series of events' (p. ). But how tight is the relationship between mental emulation and mental imagery?. To cast further light on this problem, we compared A functional relationship between imagery and perception is also documented by classic psychological. General histories of the concept of imagination, that cover Aristotle's seminal When it functions in perception it is appropriately called the common sense, and . that he in no way intends to cast doubt on the reality of imagery experience.
A number of related findings point in the same direction: There is also now considerable evidence to suggest that the eye movements of REM sleep or some of them are enactments of the movements that would be made if the dreamer were actually seeing the things being dreamed about. However, more recent research, using the much improved eye-tracking technology available today, seems to have largely removed the reasons for doubt, and to have confirmed the original claims Herman et al.
Thus, our ability to recognize objects and colors in peripheral vision i. Most of the cone cells are in, or fairly close to, the fovea, and, as one moves outwards into the periphery, they soon become very sparsely distributed.
The light sensitive cells in the peripheral retina are not only relatively widely spaced and so unable to resolve much detailbut are mostly rods, which do not register color at all, and which do not function except in low light Curcio et al.
The main function of daytime peripheral vision seems to be the detection of movement, which attracts the attention, and usually leads to the making of a saccade that brings whatever is moving into foveal vision, where it can be recognized. This does not seem to match most people's imagery experience, and does not appear to be consistent with most accounts of the cognitive properties and functions of imagery.
One possibility is that eye movements are stored in memory along with the images [i. If so, then eye movements might play an important role in allowing one to visualize a montage, a composite created on the basis of memories of multiple fixations. That is, eye movements could trigger sequences of memories and could also help us to position correctly each image of a part of the field relative to other parts. However, despite the fact that this proposal appears to be a significant departure from earlier versions of quasi-pictorialism, Kosslyn scarcely mentions it in his subsequent theoretical writings, such as his review article, or his most recent book on imagery Kosslyn, ; Kosslyn et al.
It also seems to be at odds with current ideas about how it is that we normally see the world as essentially stable, despite the fact that the image on the retina and thus also its representation in the retinotopic maps of the early visual system constantly jitters about, changing frequently, rapidly, and irregularly as the eyes move.
Mental Imagery > Notes (Stanford Encyclopedia of Philosophy)
Furthermore, Little is carried over from one fixation to the next; we do not build a visual world by pasting together samples calibrated with efference copy, but simply perceive what is currently available, plus a gist and a few previously attended objects.
The points are not unconnected. Thomas argues that the concepts of consciousness and imagination are much more closely connected with one another than is commonly realized; that, indeed, before the 17th century, imagination occupied a very large part of the conceptual space since taken over by consciousness.
Aristotle, who may well be said to have invented the concept of imagination Juhasz, ; Schofield, ; and see Rees, n. During later antiquity, the Aristotelian concept of phantasia developed into the richer Latin concept of imaginatio which became our imagination Watson, ; Cocking, Virtually every philosopher, from ancient times until well into the 20th century, implicitly accepted Aristotle's definition White, part 1; Brann, ; Thomas, aand most modern dictionaries still say something similar.
The currency of the idea that imagination is the source of artistic creativity and, latterly, creativity in other spheres, such as science e. Saintsbury, ; Osbourne, ; Cocking, ; see also Kearney, The connection here with imagery remains strong. Philostratus or Apollonius, whose words are supposedly being reported argues that, as opposed to simply producing a likeness of a living model, when a sculptor produces a statue of a god whom he has never actually seen, he must be relying upon his imagination i.
It is clear that both Philostratus and the Romantic theorists of imagination continued to believe that 'imagination' primarily means the power to produce or experience imagery Robson, ; Brann, For Coleridge the power of artistic creativity is, quite explicitly, "secondary imagination. In The Concept of MindGilbert Ryle declared that "There is no special Faculty of Imagination, occupying itself single-mindedly in fancied viewings and hearings", and in the latter half of the 20th century such deflationary views of the imagination perhaps in reaction to its earlier inflation by Romanticism became commonplace amongst analytic philosophers see Thomas, Not only was the faculty qua faculty called into question, but the very notion of imagining.
Many late 20th century philosophers held, in effect, that 'imagine' is a polysemous verb, used to mean different, sometimes quite unrelated, things on different occasions: By contrast, White part 2 argued that 'imagine' does have a true meaning — it means something like "think of as possibly being so" — but that it has no conceptual connection whatsoever with imagery.
Views similar to White's now seem to be quite widespread, though they are rarely defended in any detail if at all e. Of course, other contemporary philosophers of imagination do not share these deflationary views e. Warnock,; Brann, ; Thomas, a; McGinn, ; Crowther,and the view that imagination is a coherent concept, closely related to the concept of imagery, has been explicitly defended by Thomas a, b, and Kind This view also finds some support in the arguments of Rowlands a, b and Lycan These need not, however, be the sort of internal symbolic tokens to which enactivists object.
But Paivio, amongst others, holds that imagery can be at work in our cognitive processes without our being consciously aware of it. The question is whether such unconscious perceptual representations deserve to be called mental images, and the answer will depend, at least in part, on whether one has a representational or an experiential concept of imagery see section 1.
Furthermore, Johansson et al. Fodor, of course, is the leading proponent of the view that all mental representation is, or depends upon, mentalese, the amodal language of thought. Other Quasi-Perceptual Phenomena 1. For more on Jaensch, and the racialist framework within which his theory of eidetic imagery was developed, see Supplement: Random dot stereograms were introduced by Julesz as a tool for studying stereoscopic vision.
An illustrative example somewhat imperfect, owing to the limitations of web graphics is shown in figure 1. The two sides of the stereogram are identical except that the dots in a square region in the center of the left-hand image have been shifted a little to the right as compared with those in the right-hand image.
This difference is too slight to be visible to even quite careful inspection. However, when the stereogram is viewed through a stereoscope so that the left-hand pattern is presented only to the left eye, and the right-hand only to the right, they will fuse into a single square percept with the central, shifted, square region appearing raised in depth.
Of course, the shifted area does not have to be square, so other raised or depressed shapes can also be obtained. This would require, at a minimum, a pixel perfect memory for the exact relative positions of several tens of thousands of dots. She was also shown four different versions of the right-hand part of a 10, dot stereogram each with a different shaped region shifted relative to the left-hand imageand then the next day was shown the corresponding left-hand pattern.
It is reported that she was then able to use her eidetic images of each of the four versions of the right-hand pattern, in turn, to experience four differently shaped regions standing out in depth. Given what is now known about the relatively low resolving power of the various components of the human visual system retina, primary visual cortex, etc. Although there are well attested reports in the psychology literature of other people with remarkable mnemonic abilities with what are popularly, though misleadingly, called "photographic memories"none of their genuinely impressive accomplishments remotely resemble this feat ascribed to Elizabeth Neisser, Part 7.
From the Hellenistic to the Early Modern Era 1.
Not to be confused with his uncle, also a philosopher, Giovanni Pico della Mirandola. The Complete Iconophile 1. Although many philosophers now associate this view mainly with Berkeley's immediate target, Lockein fact it goes back at least to Aristotle De Intrepretatione 16a; De Anima band, indeed, went virtually unquestioned by language theorists throughout the intervening centuries Wollock, The Perky Experiment 1.
But see Schwitzgebel for a qualified defense and description of Titchener's introspective methodology. The reputation of Wundt, who did not use introspection of this now deprecated kind Danziger, has seen a considerable revival in recent decades e.
It is not apparent that Perky took any deliberate steps to induce relaxation in her subjects, but Segal found it essential. Thanks to Orne and others, psychologists today are very much more alert than they once were to the need to take account of the social psychology and social context of the experimental situation when working with human subjects see supplement: Jaensch, Freud, and Gestalt Psychology 1.
Burbridge,Galton's claims in this regard are not truly supported by the actual data he gathered, as well as being contradicted by the results of their own attempt to replicate his findings. They conclude that there is no good reason to believe that scientists tend to be unusually deficient in imagery.
More recently, reflective scientists and engineers seem more likely to claim that imagery plays a vital role in their professional thought processes Ferguson,; Shepard, a,b; Deutsch, ; Miller, ; Barsalou, ; Damasio, Behaviorist Iconophobia and Motor Theories of Imagery 1.
Watson also mentions Fernald's work on imagery types in this connection. Many psychologists in this period believed that people could usefully be classified into psychological types according to the preferred or predominant sensory mode of their imagery. Thus some people "visiles" might think mostly in visual imagery, others "audiles" in auditory imagery, others in motor or kinaesthetic imagery "motiles"and so on, and these types might be expected to be found to correlate with individual differences in cognitive abilities or personality see Angell, chap.
Fernald's findings indicate that the classification of people into imagery types was likely to less straightforward than had previously been realized, as the modes of imagery people report are sensitive to situational and contextual variables.
I know of no evidence, however, that, when Watson was writing, anyone but he saw Fernald's work as throwing the theory of imagery types let alone the very concept of imagery, or psychology itself into crisis. Neither Fernald herself, nor Titchener seem to have thought it did, and certainly her work aroused nothing like the widespread controversy of the imageless thought debate.
Fernald's work did perhaps pave the way for quite devastating critiques of imagery type theory by the likes of Thorndike ch. The theory has never recovered from those critiques, but they came later. There are several cases described in the neurological literature in which people have lost their onetime ability to consciously experience visual imagery, due to some sort of brain damage, even though their perceptual abilities remained relatively unimpaired Brain, ; Basso et al.
In most of these cases, however, the brain damage does give rise to other fairly obvious cognitive impairments of some sort, none of which Watson seems to have suffered from. However, more recently, Zeman et al. It is not impossible that Watson may have experienced a similar event. It remains unlikely, however, given Watson's relatively young age at the time, and the fact that he does not seem to have suffered from any further strokes or other neurological problems around this time.
Indeed, it was concern about the change he noticed in his mental experience that let him to consult a doctor about it, and so bring it to scientific attention. Skinner, it should be said, resisted the reification of experiences in general quite as much as he resisted that of images in particular. That is not to say that Dual Coding theory provides the only viable account of the selective interference phenomenon. Two tasks that simultaneously call upon the same subsystem may be expected to interfere with each other.
Baddeley, unlike Paivio, does not seem to be committed to the storage of imaginal and verbal memories in separate long term memory stores. Conceptual Issues in Dual Coding Theory 1. None of the arguments made in this section are intended to rule out the possibility that cognition might also involve other sorts of non-conscious representational codes.
These might inlcude not only mentalese conceived as the underlying code of our thought processesbut also, perhaps, specialized representational systems involved in the processing that on some views goes on within informationally encapsulated mental modules, including, perhaps, sensory processing modules Fodor, ; Pylyshyn, b.
A fully consistent defense of the unity and cohesiveness of the imagery code may not be entirely compatible with this sort of Empiricism. However, it seems to me that I can and do have imagery experiences that are simultaneously visual and auditory.
For example, if I imagine a metal pan falling to the ground, I can both "see" the fall and "hear" the crash.
McGinn may have made a case for thinking it is impossible or very difficult to have two separate, unrelated images at the same time regardless of modebut it does not necessarily follow that we cannot have unitary imagery experiences with more than one sensory aspect. The most direct textual evidence that Aristotle considered the imagination and the common sense to be fundamentally the same faculty is to be found in De Insomniis a and De Memoria a.
Kant's view of the relationship between imagination and perception seems, in the relevant respects, to have been broadly similar to this as, of course, are the views of a myriad other thinkers, past and present, directly or indirectly influenced by Aristotle.
The Kantian imagination, the einbildungskraft, is primarily responsible for the synthesis of the manifold of experience i. It should be noted that Paivio explicitly denies that there is an Aristotelian common sense Paivio, p. There are alternative and, arguably, less anachronistic interpretations of Aristotle's theory that Paivio might well find less objectionable see, e. This does not stand up to examination, however. It is true that the hypothesis of the mentalese code enables a simple and appealing explanation of an otherwise somewhat puzzling phenomenon.
If information is stored in and retrieved from memory in the form of mentalese, it will clearly need to be translated into a natural language e. On this basis, the tip of the tongue phenomenon may readily be explained as arising from a successful episode of retrieval from storage, followed by a failure of the stage of translation into natural language. However, even if this is right, mentalese is still functioning as an explanans here, and not an explanandum. It may be arguable that, because the explanation is principled and fairly simple, the tip of the tongue phenomenon provides relatively direct experiential evidence for the reality of mentalese as, say, Brownian motion provides relatively direct, easily observed evidence for the reality of moleculesbut that is not at all the same as having direct experience of mentalese per se any more than seeing Brownian motion through the microscope is seeing molecules.
It is a far cry from the sort of direct, quasi-sensuous phenomenal experience that we enjoy of imagery and inner speech. The tip of the tongue feeling may perhaps be best understood as one of those vague and contentless fringe consciousness phenomena discussed by Mangan When we experience imagery or inner speech we are normally perhaps even ipso facto aware of its intentional content, of what is being represented.
By contrast, it is of the essence of the tip of the tongue phenomenon that we are not aware of what if anything is getting represented. The Quasi-Pictorial Theory of Imagery 1. Kosslyn does not claim that the specific, LISP-like format of deep representation shown in figure 4. It is just his illustration. Even today, little is known about how such information might actually be represented if it actually is.
It is perhaps worth noting again that not only is the functional architecture of Descartes' theory of visual perception and imagination as presented in the Treatise of Man and the Optics Descartes,virtually identical to that of Kosslyn's theory, but also that the Cartesian mental image functions as a merely quasi picture.
Descartes insists that it is of no consequence whether the inner images of his theory formed on the surface of the pineal gland, the Cartesian visual buffer actually resemble the things they represent.
All that really matters is that they are such as to stimulate the soul functionally equivalent, in this respect, to Kosslyn's mind's eye function in such a way as to cause it to have the appropriate experiences Optics: Discourse 4; see Hyman, Of course, it turns out that, despite these caveats, the Cartesian inner image is in fact a picture that resembles what it represents, being during vision a point-by-point projection of the retinal image upon the pineal surface.
However, it also turns out that Kosslyn holds that when his quasi-picture is actually instantiated in the brain, it is rather more literally picture-like than the functional level theory demands see next note. Pylyshyna, b argues that much of the superficial plausibility of theories of this type depends upon this equivocation.
They slide between making appeal to pictures in a fairly literal sense, and appealing to some notion of a quasi-picture something that is not really a picture at all. The literal picture in the head theory is intuitively appealing, but clearly false, whereas the quasi-picture not-really-a-picture theory, while not so obviously false, has no more intrinsic intuitive appeal than explicitly non-pictorial views like Pylyshyn's own. Adjacent regions of the visual cortex correspond to adjacent areas on the retina such that, during vision, the two-dimensional spatial pattern of excitation of the cortical neurons corresponds topologically to the pattern of illumination in the optical image formed on the retina.
If, as Kosslyn now holds, these retinotopic maps are the embodiment of his theory's visual buffer, this means that loci in the brain that represent the presence of the same sorts of features e. Almost half of the retinotopic map in primary visual cortex V1 is devoted to mapping the fovea, the small central part of the retina where the light sensitive cells are packed most densely and where most of the color-sensitive cone cells are found.
The mnemonic effects of imagery have also been demonstrated in the congenitally blind Craig, ; Jonides et al. Some argue that the congenitally blind may even experience visual imagery, especially in dreams Keilkopf, ; Kaski, ; Aleman et al. The more generally accepted view, however, is that although people blinded later in life often continue to experience visual imagery for many years, those blind from birth or early childhood do not.
When they use visual language in describing their dreams and other imaginings, they are speaking metaphorically about their spatial understanding, or understanding in general Schlaegel, ; Berger et al.
Furthermore, the pineal gland is a hypothetical candidate for producing a mind's eye; Rick Strassman and others have postulated that during near-death experiences NDEs and dreamingthe gland might secrete a hallucinogenic chemical N,N-Dimethyltryptamine DMT to produce internal visuals when external sensory data is occluded. The hypothesized condition where a person lacks a mind's eye is called aphantasia.
The term was first suggested in a study. Another is of the pictures summoned by athletes during training or before a competition, outlining each step they will take to accomplish their goal.
Calling up an image in our minds can be a voluntary act, so it can be characterized as being under various degrees of conscious control. According to psychologist and cognitive scientist Steven Pinker our experiences of the world are represented in our minds as mental images. These mental images can then be associated and compared with others, and can be used to synthesize completely new images.
In this view, mental images allow us to form useful theories of how the world works by formulating likely sequences of mental images in our heads without having to directly experience that outcome.
Whether other creatures have this capability is debatable. There are several theories as to how mental images are formed in the mind. These include the dual-code theorythe propositional theory, and the functional-equivalency hypothesis. The dual-code theory, created by Allan Paivio inis the theory that we use two separate codes to represent information in our brains: Image codes are things like thinking of a picture of a dog when you are thinking of a dog, whereas a verbal code would be to think of the word "dog".
When abstract words are thought of, it is easier to think of them in terms of verbal codes—finding words that define them or describe them. With concrete words, it is often easier to use image codes and bring up a picture of a human or chair in your mind rather than words associated or descriptive of them. The propositional theory involves storing images in the form of a generic propositional code that stores the meaning of the concept not the image itself.
The propositional codes can either be descriptive of the image or symbolic. They are then transferred back into verbal and visual code to form the mental image.9.2 Mental Imagery
Research has occurred to designate a specific neural correlate of imagery; however, studies show a multitude of results. Most studies published before suggest neural correlates of visual imagery occur in brodmann area This ability is crucial to problem-solving tasks, memory, and spatial reasoning.
They found that inhibition of these areas through repetitive transcranial magnetic stimulation rTMS resulted in impaired visual perception and imagery. Furthermore, research conducted with lesioned patients has revealed that visual imagery and visual perception have the same representational organization. This has been concluded from patients in which impaired perception also experience visual imagery deficits at the same level of the mental representation.
This deficit prevented him from being able to recognize objects and copy objects fluidly. Surprisingly, his ability to draw accurate objects from memory indicated his visual imagery was intact and normal. These findings conflict with previous research as they suggest there is a partial dissociation between visual imagery and visual perception.
Schlegel and colleagues  conducted a functional MRI analysis of regions activated during manipulation of visual imagery.