Perceptual systems respond to proximal stimuli by forming mental representations of distal stimuli. A central goal for the philosophy of perception is to characterize the representations delivered by perceptual systems. It may be that all perceptual representations are in some way proprietarily perceptual and differ from the representational format of thought (Dretske 1981; Carey 2009; Burge 2010; Block ms.). Or it may instead be that perception and cognition always trade in the same code (Prinz 2002; Pylyshyn 2003). This paper rejects (...) both approaches in favor of perceptual pluralism, the thesis that perception delivers a multiplicity of representational formats, some proprietary and some shared with cognition. The argument for perceptual pluralism marshals a wide array of empirical evidence in favor of iconic (i.e., image-like, analog) representations in perception as well as discursive (i.e., language-like, digital) perceptual object representations. (shrink)

Short‐term memory in vision is typically thought to divide into at least two memory stores: a short, fragile, high‐capacity store known as iconic memory, and a longer, durable, capacity‐limited store known as visual working memory (VWM). This paper argues that iconic memory stores icons, i.e., image‐like perceptual representations. The iconicity of iconic memory has significant consequences for understanding consciousness, nonconceptual content, and the perception–cognition border. Steven Gross and Jonathan Flombaum have recently challenged the division between iconic memory and VWM by (...) arguing against the idea of capacity limits in favor of a flexible resource‐based model of short‐term memory. I argue that, while VWM capacity is probably governed by flexible resources rather than a sharp limit, the two memory stores should still be distinguished by their representational formats. Iconic memory stores icons, while VWM stores discursive (i.e., language‐like) representations. I conclude by arguing that this format‐based distinction between memory stores entails that prominent views about consciousness and the perception–cognition border will likely have to be revised. (shrink)

The computational view of mind rests on certain intuitions regarding the fundamental similarity between computation and cognition. We examine some of these intuitions and suggest that they derive from the fact that computers and human organisms are both physical systems whose behavior is correctly described as being governed by rules acting on symbolic representations. Some of the implications of this view are discussed. It is suggested that a fundamental hypothesis of this approach is that there is a natural domain of (...) human functioning that can be addressed exclusively in terms of a formal symbolic or algorithmic vocabulary or level of analysis. Much of the paper elaborates various conditions that need to be met if a literal view of mental activity as computation is to serve as the basis for explanatory theories. The coherence of such a view depends on there being a principled distinction between functions whose explanation requires that we posit internal representations and those that we can appropriately describe as merely instantiating causal physical or biological laws. In this paper the distinction is empirically grounded in a methodological criterion called the " cognitive impenetrability condition." Functions are said to be cognitively impenetrable if they cannot be influenced by such purely cognitive factors as goals, beliefs, inferences, tacit knowledge, and so on. Such a criterion makes it possible to empirically separate the fixed capacities of mind from the particular representations and algorithms used on specific occasions. In order for computational theories to avoid being ad hoc, they must deal effectively with the "degrees of freedom" problem by constraining the extent to which they can be arbitrarily adjusted post hoc to fit some particular set of observations. This in turn requires that the fixed architectural function and the algorithms be independently validated. It is argued that the architectural assumptions implicit in many contemporary models run afoul of the cognitive impenetrability condition, since the required fixed functions are demonstrably sensitive to tacit knowledge and goals. The paper concludes with some tactical suggestions for the development of computational cognitive theories. (shrink)

What is the purpose of perception? And how might the answer to this question help distinguish perception from other mental processes? Block’s landmark book, The.

We argue that episodic remembering, understood as the ability to re-experience past events, requires a particular kind of introspective ability and understanding. It requires the understanding that first person experiences can represent actual events. In this respect it differs from the understanding required by the traditional false belief test for children, where a third person attribution (to others or self) of a behavior governing representation is sufficient. The understanding of first person experiences as representations is also required for problem solving (...) with images. In support of this argument we review developmental evidence that children's episodic remembering is independent of and emerges after mastery of the false belief task but emerges together with the use of imagery for solving visual rotation tasks. (shrink)

The debate between the amodal and the grounded views of cognition seems to be stuck. Their only substantial disagreement is about the vehicle or format of concepts. Amodal theorists reject the grounded claim that concepts are couched in the same modality-specific format as representations in sensory systems. The problem is that there is no clear characterization of format or its neural correlate. In order to make the disagreement empirically meaningful and move forward in the discussion we need a neurocognitive criterion (...) for representational format. I argue that efficient coding models in computational neuroscience can be used to characterize modal codes: These are codes which satisfy special informational demands imposed by sensory tasks. Additionally, I examine recent studies on neural coding and argue that although they do not provide conclusive evidence for either the grounded or the amodal views, they can be used to determine what predictions these approaches can make and what experimental and theoretical developments would be required to settle the debate. (shrink)

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of (...) acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The out- side world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the gov- erning laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Sev- eral lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual “filling in,” visual stability despite eye movements, change blindness, sensory substitution, and color perception. (shrink)

One of the principal tasks Dennett sets himself in Consciousness Explained is to demolish the Cartesian theater model of phenomenal consciousness, which in its contemporary garb takes the form of Cartesian materialism: the idea that conscious experience is a process of presentation realized in the physical materials of the brain. The now standard response to Dennett is that, in focusing on Cartesian materialism, he attacks an impossibly naive account of consciousness held by no one currently working in cognitive science or (...) the philosophy of mind. Our response is quite different. We believe that, once properly formulated, Cartesian materialism is no straw man. Rather, it is an attractive hypothesis about the relationship between the computational architecture of the brain and phenomenal consciousness, and hence one that is worthy of further exploration. Consequently, our primary aim in this paper is to defend Cartesian materialism from Dennett’s assault. We do this by showing that Dennett’s argument against this position is founded on an implicit assumption (about the relationship between phenomenal experience and information coding in the brain), which while valid in the context of classical cognitive science, is not forced on connectionism. (shrink)

When characterizing the content of a subject’s perceptual experience, does their seeing an object entail that their visual experience represents it as being a certain way? If it does, are they thereby in a position to have perceptually-based thoughts about it? On one hand, representationalists are under pressure to answer these questions in the affirmative. On the other hand, it seems they cannot. This paper presents a puzzle to illustrate this tension within orthodox representationalism. We identify several interesting morals which (...) may be drawn in response, each of which teaches us something interesting and important about perceptual experience and its interface with cognition and related phenomena. (shrink)

This article is an attempt to situate imagination within consciousness complete with its own pre-cognitive, cognitive, and meta-cognitive domains. In the first sections we briefly review traditional philosophical and psychological conceptions of the imagination. The majority have viewed perception and imagination as separate faculties, performing distinct functions. A return to a phenomenological account of the imagination suggests that divisions between perception and imagination are transcended by precognitive factors of sense of reality and non-reality where perception and imagination play an indivisible (...) role. In fact, both imagination and perception define sense of reality jointly according to what is possible and not possible. Absorption in a possible world depends on the strengths of alternative possibilities, and the relationship between core and marginal consciousness. The model may offer a parsimonious account of different states and levels of imaginal consciousness, and of how “believed-in imaginings” develop and become under some circumstances “lived-in experiences.”. (shrink)

Having, in previous papers, distinguished at least three forms of consciousness , I now further examine their differences. This examination has some surprising results. Having argued that neither C1 nor C2 is a phenomenological state?and so different from CN?I now show that CN itself is best thought of as a subclass of a larger state . CS is the set of image?representation states. CN is that set of CS states that we are also C2 about. I argue that CN states (...) should be considered a subset of CS states because they share with other CS states imagistic representational powers as opposed to the sentential ones of C1 and C2. And I argue that there are good reasons to consider any state which utilises imagistic representation as a sensation. I then show that the notion of an unconscious sensation makes sense if we think of it as a CS state that is not C2. More radically, I conclude that either it makes sense to say that there are unfelt sensations or there are felt sensations we are not conscious about. While there are good reasons for saying one or the other of these surprising things, I argue that the second, more radical sounding, alternative is actually better motivated?and not quite so surprising as it sounds. (shrink)

A-consciousness may be regarded as the visibility of information that is the output of a process within a community of other processes. The most prominent function of “public” dissemination of information is giving access to it to processes whose relevance is not clear at the moment of dissemination. The function of P-consciousness may be outside the realm of cognition.

In response to the objection that his “access-consciousness” is not really consciousness but a matter of the availability of certain information for certain kinds of processing, Block will probably have to argue that consciousness in a more basic, familiar, traditional sense is an essential component of any instance of access-consciousness and thus justifies the name.

When we see an object, we also represent those parts of it that are not visible. The question is how we represent them: this is the problem of amodal perception. I will consider three possible accounts: (a) we see them, (b) we have non-perceptual beliefs about them and (c) we have immediate perceptual access to them, and point out that all of these views face both empirical and conceptual objections. I suggest and defend a fourth account, according to which we (...) represent the occluded parts of perceived objects by means of mental imagery. This conclusion could be thought of as a (weak) version of the Strawsonian dictum, according to which “imagination is a necessary ingredient of perception itself”. (shrink)

In common sense consciousness has a fairly determinate content – the (single) way an experience feels, the (single) line of thought being consciously followed. The determinacy of the object may be achieved by linking Block's two concepts, so that as long as we hold on to the determinacy of content we are unable to separate P and A.