Abstract: What do pictures and mental images have in common? The contemporary tendency to reject mental picture theories of imagery suggests that the answer is: not much. We show that pictures and visual imagery have something important in common. They both contribute to mental simulations: pictures as inputs and mental images as outputs. But we reject the idea that mental images involve mental pictures, and we use simulation theory to strengthen the anti-pictorialist's case. Along the way we try to account for caricature and for some basic features of pictorial representations

Abstract: The “Perky effect” is the interference of visual imagery with vision. Studies of this effect show that visual imagery has more than symbolic properties, but these properties differ both spatially (including “pictorially”) and temporally from those of vision. We therefore reject both the literal picture-in-the-head view and the entirely symbolic view

Abstract: Is mental imagery pictorial? In Pylyshyn's view no empirical data provides convincing support to the “pictorial” hypothesis of mental imagery. Phenomenology, Pylyshyn says, is deeply deceiving and offers no explanation of why and how mental imagery occurs. We suggest that Pylyshyn mistakes phenomenology for what it never pretended to be. Phenomenological evidence, if properly considered, shows that mental imagery may indeed be pictorial, though not in the way that mimics visual perception. Moreover, Pylyshyn claims that the “pictorial hypothesis” is flawed because the interpretation of “picture-like” objects in mental imagery takes a homunculus. However, the same point can be objected to Pylyshyn's own conclusion: if imagistic reasoning involves the same mechanisms and the same forms of representation as those that are involved in general reasoning, if they operate on symbol-based representations of the kind recommended by Pylyshyn (1984) and Fodor (1975), don't we need a phenomenological homunculus to tell an imagined bear from the real one?

Abstract: But say you,surely there is nothing easier than to imagine trees,for instance,in a park, or books existing in a closet, and nobody by to perceive them. I answer, you may so, there is no dif?culty in it:but what is all this,I beseech you,more than framing in your mind certain ideas which you call books and trees, and at the same time omitting to frame the idea of anyone that may perceive them? But do you not yourself perceive or think of them all the while? This therefore is nothing to the purpose: it only shows you have the power of imagining or forming ideas in your mind;but it doth not shew that you can conceive it possible, the objects of your thought may exist without the mind: to make out this, it is necessary that you conceive them existing unconceived or unthought of, which is a manifest repugnancy

Abstract: The Way of Ideas died an ignoble death, committed to the flames by behaviorist empiricists. Ideas, pictures in the head, perished with the Way. By the time those empiricists were supplanted at the helm by functionalists and causal theorists, a revolution had taken place in linguistics and the last thing anyone wanted to do was revive images as the medium of thought. Currently, some but not all cognitive scientists think that there probably are mental images - experiments in cognitive psychology (e.g. Shepard and Metzler 1971) have shown it to be plausible to posit mental images. Even so, the phenomenon of mental imagery has been largely regarded as peripheral in cognition, perhaps even epiphenomenal. Images cannot fix the content of thought (intentions, rules), the Wittgenstein story went. The central processes of thought, so the post-Wittgenstein story goes, require a propositional representation system, a language of thought, universal and modeled on the machine languages of computers. The language of thought is compositional, productive, and, leading advocates argue, has a causal semantics. Images lack all of these essential qualities and so are hopeless as key players in thinking

Abstract: The presence of spatial patterns of activity in the brain is suggestive of image-exploiting processes in vision and mental imagery, but not conclusive. Only behavioral evidence can confirm or disconfirm hypotheses about whether, and how, the brain uses images in its information-processing, and the arguments based on such evidence are still inconclusive

Abstract: Pylyshyn rightly argues that the neuroscientific data supporting the involvement of the visual system in mental imagery is largely irrelevant to the question of the format of imagistic representation. The purpose of this commentary is to support this claim with a further argument

Abstract: Visualizings, the simplest imaginings which employ visual imagery, have certain characteristic features; they are perspectival, for instance. Also, it seems that some but not all of our visualizings are imaginings of seeings. But it has been forcefully argued, for example by M.G.F. Martin and Christopher Peacocke, that all visualizings are imaginings of visual sensations. I block these arguments by providing an account of visualizings which allows for their perspectival nature and other features they typically have, but which also explains how we can visualize things without thereby imagining visual sensations

Abstract: The problem seems apparent even in Glasgow's term ``depict'', which is used by way of contrast with ``describe''. Now ``describe'' refers relatively unproblematically to strings of symbols, such as those in this written sentence, that are systematically interpretable as propositions describing objects, events, or states of affairs. But what does ``depict'' mean? In the case of a picture -- whether a photo or a diagram -- it is clear what depict means. A picture is an object (I will argue below that it is an analog object, relative to what it is a picture of) and it DEPICTS yet another object: the object it is a picture OF. But in the case of an array, whether described formally, with numerical coordinates, or stored in a machine, or ``depicted'' diagrammatically by way of a secondary illustration, it is not at all clear whether the entity in question is indeed a picture, or merely yet another set of symbols that is INTERPRETABLE as referring to a picture, which picture in turn depicts an object! It is clear that we are dealing with many layers of interpretation here already, and so far we are still talking only about external objects (such as pictures, symbols and objects simpliciter). We still have not gotten to MENTAL objects, such as mental ``images''

Abstract: This debate, principally between myself (Nigel Thomas) and Patrick Hayes, the well known computer scientist and Artificial Intelligence researcher, took place through the internet mailing list for the discussion of the scientific study of consciousness, PSYCHE-D (moderated by Patrick Wilken), which is associated with the on-line journal PSYCHE. The discussion touches on the various different senses in which the expression "mental image" may be used, the underlying cognitive mechanisms of imagery, and the relevance of an understanding of imagery to the understanding of conscious thought, and thought in general. As the debate became rather 'unthreaded' on the list, following it through this page may help the reader to better understand what was going on

Abstract: Both imagery and imagination play an important part in our mental lives. This article, which has three main sections, discusses both of these phenomena, and the connection between them. The first part discusses mental images and, in particular, the dispute about their representational nature that has become known as the _imagery debate_ . The second part turns to the faculty of the imagination, discussing the long philosophical tradition linking mental imagery and the imagination—a tradition that came under attack in the early part of the twentieth century with the rise of behaviorism. Finally, the third part of this article examines modal epistemology, where the imagination has been thought to serve an important philosophical function, namely, as a guide to possibility

Abstract: With admirable clarity, Pylyshyn shows that there is little evidence that mental imagery is strongly constrained to be analog. He urges that imagery must be considered part of a more general symbolic system. The ultimate solution to the challenges of image theory, however, rest on understanding the manner in which mental imagery is both a symbolic and an analog system

Abstract: In Gregory, Richard. Oxford Companion to the Mind (Second Edition, 2006) Oxford University Press

Abstract: Jacques Mehler was notoriously charitable in embracing a diversity of approaches to science and to the use of many different methodologies. One place where his ecumenism brought the two of us into disagreement is when the evidence of brain imaging was cited in support of different psychological doctrines, such as the picture-theory of mental imagery. Jacques remained steadfast in his faith in the ability of neuroscience data (where the main source of evidence has been from clinical neurology and neuro-imaging) to choose among different psychological positions. I personally have seen little reason for this optimism so Jacques and I frequently found ourselves disagreeing on this issue, though I should add that we rarely disagreed on substantive issues on which we both had views. This particular bone of contention, however, kept us busy at parties and during the many commutes between New York and New Jersey, where Jacques was a frequent visitor at the Rutgers Center for Cognitive Science. Now that I am in a position where he is a captive audience it seems an opportune time to raise the question again

Abstract: It is generally accepted that there is something special about reasoning by using mental images. The question of how it is special, however, has never been satisfactorily spelled out, despite more than thirty years of research in the post-behaviorist tradition. This article considers some of the general motivation for the assumption that entertaining mental images involves inspecting a picture-like object. It sets out a distinction between phenomena attributable to the nature of mind to what is called the cognitive architecture, and ones that are attributable to tacit knowledge used to simulate what would happen in a visual situation. With this distinction in mind, the paper then considers in detail the widely held assumption that in some important sense images are spatially displayed or are depictive, and that examining images uses the same mechanisms that are deployed in visual perception. I argue that the assumption of the spatial or depictive nature of images is only explanatory if taken literally, as a claim about how images are physically instantiated in the brain, and that the literal view fails for a number of empirical reasons – for example, because of the cognitive penetrability of the phenomena cited in its favor. Similarly, while it is arguably the case that imagery and vision involve some of the same mechanisms, this tells us very little about the nature of mental imagery and does not support claims about the pictorial nature of mental images. Finally, I consider whether recent neuroscience evidence clarifies the debate over the nature of mental images. I claim that when such questions as whether images are depictive or spatial are formulated more clearly, the evidence does not provide support for the picture-theory over a symbol-structure theory of mental imagery. Even if all the empirical claims were true, they do not warrant the conclusion that many people have drawn from them: that mental images are depictive or are displayed in some (possibly cortical) space. Such a conclusion is incompatible with what is known about how images function in thought. We are then left with the provisional counterintuitive conclusion that the available evidence does not support rejection of what I call the “null hypothesis”; namely, that reasoning with mental images involves the same form of representation and the same processes as that of reasoning in general, except that the content or subject matter of thoughts experienced as images includes information about how things would look

Abstract: In the past decade there has been renewed interest in the study of mental imagery. Emboldened by new findings from neuroscience, many people have revived the idea that mental imagery involves a special format of thought, one that is pictorial in nature. But the evidence and the arguments that exposed deep conceptual and empirical problems in the picture theory over the past 300 years have not gone away. I argue that the new evidence from neural imaging and clinical neuropsychology does little to justify this recidivism because it does not address the format of mental images. I also discuss some reasons why the picture theory is so resistant to counterarguments and suggest ways in which non-pictorial theories might account for the apparent spatial nature of images.

Abstract: People have always wondered how thinking takes place and what thoughts are constructed from. We typically experience our thoughts as involving pictorial (or sensory) contents or as being in words. Although this idea has been enshrined in psychology as the “dual code” theory of reasoning and memory, serious questions have been raised concerning this view. It appears that whatever the form of our thoughts it is unlikely that it is anything like our experience of them. But if thought is not in pictures or words, what form does it take? If we do not sometimes think in words, then what actually goes on when we think by engaging in an “inner dialogue”? And if we do not sometimes think in pictures, what goes on when we reason by creating and examining “mental images”?

Abstract: The questions addressed in research on mental imagery have become more refined as experimental techniques have become more exact. One issue that has emerged in current work is whether, or in what ways, imaging is like perceiving. Daniel Reisberg and Deborah Chambers have devised a series of experiments that put that question to the test by asking whether images can be reinterpreted in the same ways that perceptual objects can be reinterpreted. They argue that the evidence points to a negative conclusion. Other psychologists have responded, and a debate has ensued. The debate, intersects with philosophy in two ways: (i) philosophers have appropriated the empirical results in defence of their views on imagery; and (ii) psychologists on both sides have argued about the role of 'philosophical considerations' in evaluating the results. My aim is to clarify the issues at stake, to dispel certain confusions apparent in the literature, and to show that recent research does not support the claim that imaging is unlike perceiving in specific respects

Abstract: AI research concerning the connection between seeing and speaking mainly employs what is called reference semantics. Within this framework, the notion of `mental image' is often used while explaining how somebody not situated in the same perceptual context is able to anchor his understanding of an utterance describing the scene visually perceived by the speaker. We give a foundation for considering mental images as propositions with respect to a certain field of concepts: these fields have to provide a syntactically dense set of concepts distinguishing locations. The use of such propositions in the reference semantic explanations of understanding utterances about visually perceived scenes is motivated by applying Kant's idea of the introduction of new types of objects: we conceive spatial relations as relations only applicable to sortal objects, i.e., individuated objects which are synthetically introduced on a syntactically dense field providing their potential locations. The concept `mental image' which results from these preliminary studies is applied to two current projects in AI, one dealing with the semantics of particular spatial prepositions, and the other more generally concerned with the logic of the connection between visual and verbal space

Abstract: Most cognitive theories agree that a listener of a sports broadcast on radio usually imagines the scene described; the concept `mental image' appears in a specific sort of explanations. In contrast to this conception, it is argued that this concept should rather be understood as part of a certain kind of grounding explanations of the radio listener's understanding. This particular conception is based on the distinction between `specification' and `implementation' as found in the theory of abstract data types. Its application to the field of spatial concepts leads to a computational system (ANTLIMA) which exemplifies how the expression `mental image' could be used while explaining a speaker's ability to control the resolvability of ambiguities in an objective report of what the speaker sees

Abstract: images. But clearly, it only begs the deeper questions

Abstract: The imagery debate re-enacts controversies persisting since Descartes. The controversy remains important less for what we can learn about visual imagery than about cognitive science itself. In the tradition of Arnauld, Reid, Bartlett, Austin and Ryle, Pylyshyn’s critique exposes notorious mistakes being unwittingly rehearsed not only regarding imagery but also in several independent domains of research in modern cognitive science

Abstract: The imagery debate re-enacts controversies persisting since Descartes. The controversy remains important less for what we can learn about visual imagery than about cognitive science itself. In the tradition of Arnauld, Reid, Bartlett, Austin and Ryle, Pylyshyn's critique exposes notorious mistakes being unwittingly rehearsed not only regarding imagery but also in several independent domains of research in modern cognitive science

Abstract: In their study of reasoning with diagrammatic and non-diagrammatic representations, Larkin and Simon (1987) are concerned with _external_ representations and explicitly avoid drawing inferences about the bearing of their work on the issue of internal, mental representations. Nonetheless, we may infer the bearing of their work on internal representations from the theories of Kosslyn, Finke and other ‘pictorialists’ who take internal representations to be importantly like external ones regarding their ‘privileged’ spatial properties of depicting and resembling their referents. Thus, Finke (1990) suggests that “perceptual interpretive processes are applied to mental images in much the same way that they are applied to actual physical objects. In this sense, imagined objects can be “interpreted” much like physical objects” (1990, p. 18). Elsewhere he suggests that “The image discoveries which then ‘emerge’ resemble the way perceptual discoveries can follow the active exploration and manipulation of physical objects” (1990, p. 171)

Abstract: are needed on which the contending accounts deliver different predictions. The question of re-interpreting images can be seen

Abstract: One property of the emulator framework presented by Grush is that imagery operates off-line. Contrary to this viewpoint, we present evidence showing that mental rotation of a simple figure modulates low-level features of drawing articulation. This effect is dependent upon the type of rotation, suggesting a more integrative online role for imagery than proposed by the target article

Abstract: Until a few years ago, Cognitive Science was firmly wedded to the notion that cognition must be explained in terms of the computational manipulation of internal representations or symbols. Although many people still believe this, the consensus is no longer solid. Whether it is truly threatened by connectionism is, perhaps, controversial, but there are yet more radical approaches that explicitly reject it. Advocates of "embodied" or "situated" approaches to cognition (e.g., Smith, 1991; Varela _et al_ , 1991, Clancey, 1997) argue that thought cannot be understood as entirely internal. Furthermore, it is argued that autonomous robots can be designed to behave more intelligently if representationalist programming techniques are avoided (Brooks, 1991), and that the way our brains control our behavior is better understood in terms of chaos and dynamical systems theory rather than as any sort computation (e.g., Freeman & Skarda, 1990; Van Gelder & Port, 1995; Van Gelder, 1995; Garson, 1996)

Abstract: Can theories of mental imagery, conscious mental contents, developed within cognitive science throw light on the obscure (but culturally very significant) concept of imagination? Three extant views of mental imagery are considered: quasi-pictorial, description, and perceptual activity theories. The first two face serious theoretical and empirical difficulties. The third is (for historically contingent reasons) little known, theoretically underdeveloped, and empirically untried, but has real explanatory potential. It rejects the "traditional" symbolic computational view of mental contents, but is compatible with recent *situated cognition* and *active vision* approaches in robotics. This theory is developed and elucidated. Three related key aspects of imagination (non-discursiveness, creativity, and *seeing as*) raise difficulties for the other theories. Perceptual activity theory presents imagery as non-discursive and relates it closely to *seeing as*. It is thus well placed to be the basis for a general theory of imagination and its role in creative thought

Abstract: The principal temptation toward substance dualisms, or otherwise incorporating a question begging homunculus into our psychologies, arises not from the problem of consciousness in general, nor from the problem of intentionality, but from the question of our awareness and understanding of our own mental contents, and the control of the deliberate, conscious thinking in which we employ them. Dennett has called this "Hume's problem". Cognitivist philosophers have generally either denied the experiential reality of thought, as did the Behaviorists, or have taken an implicitly epiphenomenalist stance, a form of dualism. Some sort of mental duality may indeed be required to meet this problem, but not one that is metaphysical or question begging. I argue that it can be solved in the light of Paivio's "Dual Coding" theory of mental representation. This theory, which is strikingly simple and intuitive (perhaps too much so to have caught the imagination of philosophers) has demonstrated impressive empirical power and scope. It posits two distinct systems of potentially conscious representations in the human mind: mental imagery and verbal representation (which is not to be confused with 'propositional' or "mentalese" representation). I defend, on conceptual grounds, Paivio's assertion of precisely two codes against interpretations which would either multiply image codes to match sense modes, or collapse the two, admittedly interacting, systems into one. On this basis I argue that the inference that a conscious agent would be needed to read such mental representations and to manipulate them in the light of their contents can be pre-empted by an account of how the two systems interact, each registering, affecting and being affected by developing associative processes within the other

Abstract: Galton and subsequent investigators find wide divergences in people's subjective reports of mental imagery. Such individual differences might be taken to explain the peculiarly irreconcilable disputes over the nature and cognitive significance of imagery which have periodically broken out among psychologists and philosophers. However, to so explain these disputes is itself to take a substantive and questionable position on the cognitive role of imagery. This article distinguishes three separable issues over which people can be "for" or "against" mental images. Conflation of these issues can lead to theoretical differences being mistaken for experiential differences, even by theorists themselves. This is applied to the case of John B. Watson, who inaugurated a half-century of neglect of image psychology. Watson originally claimed to have vivid imagery; by 1913 he was denying the existence of images. This strange reversal, which made his behaviorism possible, is explicable as a "creative misconstrual" of Dunlap's "motor" theory of imagination

Abstract: This article defends tradition and common sense against a widespread and rarely questioned contemporary philosophical orthodoxy that underpins the entrenched and exorbitant "lingualism" of so much 20th century thought, and leads the way to extreme doctrines like cognitive relativism and eliminative materialism. It also plugs what might otherwise have seemed to be a significant hole in the argument of my Are Theories of Imagery Theories of Imagination? (which I regard as my main positive contribution so far to the understanding of the mind). For a relatively brief overview of the situation in cognitive theory and consciousness studies, as I see it, see A Stimulus to the Imagination. Click here to view the full article: Imagery and the Coherence of Imagination: a Critique of White. Earlier drafts of this article, one entitled "The White Images of Imagery and Imagination: A Critique and an Alternative", were formerly available on the net. Please make any citations to the published version. - N.J.T.T

Abstract: This paper (1) sketches a phenomenological analysis of visual mental imagery; (2) applies this analysis to the mental imagery debate in cognitive science; (3) briefly sketches a neurophenomenological approach to mental imagery; and (4) compares the results of this discussion with Dennett’s heterophenomenology

Abstract: An introduction to the science and philosophy of mental imagery.

Abstract: Since the publication of my "Are Theories of Imagery Theories of Imagination? An _Active Perception_ Approach to Conscious Mental Content," (Thomas, 1999 - henceforth abbreviated as ATOITOI on this page), a good deal of published material has appeared or has come to my attention that either provides additional support for the Perceptual Activity Theory PA theory) of mental imagery presented in ATOITOI, or that throws further doubt on the rival (picture and description) theories that are criticized there. Other relevant evidence was not mentioned in ATOITOI because I lacked the space for a proper explanation of its relevance. I hope eventually to write and publish a new account of

PA

theory, that will make use of much of this material. In the meantime this page provides citations (and, where possible, links) to the "new" support, and discussion sections that briefly explain the relevance of the cited material. Quite apart from presenting new lines of supporting evidence and argument, I hope this page will help to clarify many aspects of

Abstract: This paper sketches a phenomenological analysis of visual mental imagery and uses it to criticize representationalism and the internalist-versus-externalist framework for understanding consciousness. Contrary to internalist views of mental imagery imagery experience is not the experience of a phenomenal mental picture inspected by the mind’s eye, but rather the mental simulation of perceptual experience. Furthermore, there are experiential differences in perceiving and imagining that are not differences in the properties represented by these experiences. Therefore, externalist representationalism, which maintains that the properties of experience are the external properties represented by experience, is an inadequate account of conscious experience

Abstract: Pylyshyn's critique is powerful. Pictorial theories of imagery fail. On the other hand, the symbolic description theory he manifestly still favors also fails, lacking the semantic foundation necessary to ground imagery's intentionality and consciousness. But, contrary to popular belief, these two theory types do not exhaust available options. Recent work on embodied, active perception supports the alternative perceptual activity theory of imagery

Abstract: Defining Imagery: Experience or Representation?
Historical Development of Ideas about Imagery
Subjective Individual Differences in Imagery Experience
Theories of Imagery, and their Implications for Consciousness
Picture theory
Description theory
Enactive theory

Abstract: Michael Tye untangles the complex web of empirical and conceptual issues of the newly revived imagery debate in psychology between those that liken mental...