According to the decomposition thesis, perceptual experiences resolve without remainder into their different modality-specific components. Contrary to this view, I argue that certain cases of multisensory integration give rise to experiences representing features of a novel type. Through the coordinated use of bodily awareness—understood here as encompassing both proprioception and kinaesthesis—and the exteroceptive sensory modalities, one becomes perceptually responsive to spatial features whose instances couldn’t be represented by any of the contributing modalities functioning in isolation. I develop an argument (...) for this conclusion focusing on two cases: 3D shape perception in haptic touch and experiencing an object’s egocentric location in crossmodally accessible, environmental space. (shrink)

Our perception of where touch occurs on our skin shapes our interactions with the world. Most accounts of cutaneous localisation emphasise spatial transformations from a skin-based reference frame into body-centred and external egocentric coordinates. We investigated another possible method of tactile localisation based on an intrinsic perception of ‘skin space’. The arrangement of cutaneous receptive fields (RFs) could allow one to track a stimulus as it moves across the skin, similarly to the way animals navigate using path integration. (...) We applied curved tactile motions to the hands of human volunteers. Participants identified the location midway between the start and end points of each motion path. Their bisection judgements were systematically biased towards the integrated motion path, consistent with the characteristic inward error that occurs in navigation by path integration. We thus showed that integration of continuous sensory inputs across several tactile RFs provides an intrinsic mechanism for spatial perception. (shrink)

This report highlights and explores five questions that arose from the multisensory integration workshop at the University of Toronto on May 9th and 10th, 2014: 1. What Is Multisensory Integration? 2. Do Multisensory Percepts Involve Emergent Features? 3. What Can Multisensory Processing Tell Us about Multisensory Awareness? 4. Is Language Processing a Special Kind of Multisensory Integration? 5. What Is the Purpose of Multisensory Integration?

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: Do multisensory percepts involve emergent features?

Suppose that you are at a live jazz show. The drummer begins a solo. You see the cymbal jolt and you hear the clang. But in addition seeing the cymbal jolt and hearing the clang, you are also aware that the jolt and the clang are part of the same event. Casey O’Callaghan (forthcoming) calls this awareness “intermodal feature binding awareness.” Psychologists have long assumed that multimodal perceptions such as this one are the result of a subpersonal feature binding mechanism (...) (see Vatakis and Spence, 2007, Kubovy and Schutz, 2010, Pourtois et al., 2000, and Navarra et al., 2012). I present new evidence against this. I argue that there is no automatic feature binding mechanism that couples features like the jolt and the clang together. Instead, when you experience the jolt and the clang as part of the same event, this is the result of an associative learning process. The cymbal’s jolt and the clang are best understood as a single learned perceptual unit, rather than as automatically bound. I outline the specific learning process in perception called “unitization,” whereby we come to “chunk” the world into multimodal units. Unitization has never before been applied to multimodal cases. Yet I argue that this learning process can do the same work that intermodal binding would do, and that this issue has important philosophical implications. Specifically, whether we take multimodal cases to involve a binding mechanism or an associative process will have impact on philosophical issues from Molyneux’s question to the question of how active or passive we consider perception to be. (shrink)

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: What is multisensory integration?

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: What can multisensory processing tell us about multisensory awareness?

This chapter offers an indirect defence of the Evansian conception of egocentric space, by showing how it resolves a puzzle concerning the unity of egocentric spatial perception. The chapter outlines several common assumptions about egocentric perspectival structure and argues that a subject’s experience, both within and across her sensory modalities, may involve multiple structures of this kind. This raises the question of how perspectival unity is achieved, such that these perspectival structures form a complex whole, rather (...) than merely disunified set of individually, distinctively structured experiences. The shortcomings of variety of accounts are considered: switch accounts ; sensory accounts; transformation accounts; and ultimate accounts. These shortcomings are addressed by a further kind of account provided by the Evansian conception – an agentive account – according to which egocentrically structured experiences present the world in relation to parts of a single thing, the body as a dynamic unity. (shrink)

This paper examines Milner and Goodale’s hypothesis about the two visual streams and raises the questions of whether properties in egocentric space (commonly associated with the vision-for-action, or "dorsal," stream) can be part of the phenomenal content of perceptual experience, or only properties in allocentric space (commonly associated with the vision-for-perception, or "ventral," stream) can play this role, and how (if at all) properties in egocentric space differ from properties in allocentric space. These questions (...) are reminiscent of issues raised by Christopher Peacocke's "equal-sized trees" case: if you are looking at equal-sized trees on the side of a road, the trees will phenomenally look to you to be equally tall. But it is also true that a tree will take up more of the space in your visual field the closer it is to you. So, the equal-sized trees will also phenomenally look to you to have different heights. Your (visual) perceptual experience is not illusory. That is, the trees veridically look to you to have the same height, and they also veridically look to you to have different heights. Call the sort of issue raised here the "problem of dual looks." I provide a solution to the problem of dual looks that helps shed light on whether properties in egocentric space can be part of the phenomenal content of perceptual experience, and how (if at all) properties in egocentric space differ from properties in allocentric space. (shrink)

Our emotional states affect how we perceive the world. If I am stressed, annoyed, or irritated, I might experience the sound of children laughing and screaming as they play around the house in a negative manner — it is unpleasant, loud, piercing, and so on. Yet, if I’m in a relaxed, happy, loving mood, the very same sounds might be experienced as pleasant, playful, warm, and so on. The sounds being made by the children are the same in both cases, (...) but how they are experienced differs. The auditory experience is affected by the emotional state that I am in. I perceive the sounds differently depending on how I’m feeling. Although this might at first seem to be a trivial observation, it certainly is not. We take for granted that our perceptual experiences give rise to justified beliefs and knowledge. Thus, if my perceptual experience of an object can differ based on my emotional state, and I take my perceptual experience to justify my beliefs and even lead to knowledge, then we might have a problem. If emotions — which are not fixed and in large part uncontrolled — affect our ability to accurately perceive the world, then they may undermine the justified beliefs and knowledge gained on the basis of our perceptual experience of the world. My goal here is to explore this potential problem. -/- I consider how we might understand the effect that emotions have on the justification of our perceptual beliefs about the world, beliefs that we acquire from a variety of sensory modalities — audition, gustation olfaction, and so on. I take the problem to be associated with one of two forms of perceptual influence: penetration or multisensory integration. In any given perceptual moment there are multiple sensory modalities and mental states at play, each affecting the overall experience. Whether we understand the influence of emotion on perception as a form of non-perceptual penetration or a form of non-visual sensory perception of the inner body — interoception — the potential epistemological difficulties remain: how can we be said to acquire justified beliefs and knowledge on the basis of such influenced perceptual experience. As has been the norm, only the five exteroceptive senses of vision, audition, olfaction, taste and touch are typically discussed in the context of sensory perception. However, as I argue, there is strong reason to accept the claim that emotional experience is a form of interoception, and that interoception ought to be considered when discussing sensory perception. In this way, then, I propose that clarifying the role played by interoception in sense perception across modalities is necessary if we are to make progress on the epistemological problems at hand. (shrink)

Multisensory processing encompasses all of the various ways in which the presence of information in one sensory modality can adaptively influence the processing of information in a different modality. In Part I of this survey article, I begin by presenting a cartography of some of the more extensively investigated forms of multisensory processing, with a special focus on two distinct types of multisensory integration. I briefly discuss the conditions under which these different forms of multisensory processing (...) occur as well as their important perceptual consequences and interrelations. In Part II, I then turn to examining of some of the different possible ways in which the structure of conscious perceptual experience might also be characterized as multisensory. In addition, I discuss the significance of research on multisensory processing and multisensory consciousness for philosophical attempts to individuate the senses. (shrink)

We can perceive shapes visually and tactilely, and the information we gain about shapes through both sensory modalities is integrated smoothly into and functions in the same way in our behavior independently of whether we gain it by sight or touch. There seems to be no reason in principle we couldn't perceive shapes through other sensory modalities as well, although as a matter of fact we do not. While we can identify shapes through other sensory modalities—e.g., I may know by (...) smell (the scent of mango) that the object causing my sensory experience is round—this is not perceiving an object as shaped, but rather inferring from the character of one's sensory experience and collateral information that an object of a certain shape caused it. That it is possible to perceive shape by other modalities, however, is suggested by the case of bats and aquatic mammals like dolphins which navigate through their environment by a form of sonar. It is plausible that they have some form of auditory representation of space, and so of shape. These facts about shape perception raise important questions about the relation between those features of perceptual experience which are intrinsic to different sensory modalities and the nature of our perceptual representation of shapes, and, more generally, of the space within which we perceive shaped objects to be located. John Campbell's paper, "Molyneux's Problem" (see above), raises a number of interesting and important questions about the nature of our perception of shape properties, particularly the cross-modal nature of shape perception, and ties them to more general questions about the nature both of perceptual.. (shrink)

Neuropsychological findings used to motivate the "two visual systems" hypothesis have been taken to endanger a pair of widely accepted claims about spatial representation in conscious visual experience. The first is the claim that visual experience represents 3-D space around the perceiver using an egocentric frame of reference. The second is the claim that there is a constitutive link between the spatial contents of visual experience and the perceiver's bodily actions. In this paper, I review and assess three (...) main sources of evidence for the two visual systems hypothesis. I argue that the best interpretation of the evidence is in fact consistent with both claims. I conclude with some brief remarks on the relation between visual consciousness and rational agency. (shrink)

The first part of this survey article presented a cartography of some of the more extensively studied forms of multisensory processing. In this second part, I turn to examining some of the different possible ways in which the structure of conscious perceptual experience might also be characterized as multisensory. In addition, I discuss the significance of research on multisensory processing and multisensory consciousness for philosophical debates concerning the modularity of perception, cognitive penetration, and the individuation of (...) the senses. (shrink)

Molyneux's Question (MQ) concerns whether a newly sighted man would recognize/distinguish a sphere and a cube by vision, assuming he could previously do this by touch. We argue that (MQ) splits into questions about (a) shared representations of space in different perceptual systems, and about (b) shared ways of constructing higher dimensional spatiotemporal features from information about lower dimensional ones, most of the technical difficulty centring on (b). So understood, MQ resists any monolithic answer: everything depends on the constraints (...) faced by particular perceptual systems in extracting features of higher dimensionality from those of lower. Each individual question of this type is empirical and must be investigated separately. We present several variations on MQ based on different levels of dimensional integration—some of these are familiar, some novel adaptations of problems known elsewhere, and some completely novel. Organizing these cases in this way is useful because it unifies a set of disparate questions about intermodal transfer that have held philosophical and psychological interest, suggests a new range of questions of the same type, sheds light on similarities and differences between members of the family, and allows us to formulate a much-augmented set of principles and questions concerning the intermodal transfer of spatiotemporal organization. (shrink)

It remains controversial whether touch is a truly spatial sense or not. Many philosophers suggest that, if touch is indeed spatial, it is only through its alliances with exploratory movement, and with proprioception. Here we develop the notion that a minimal yet important form of spatial perception may occur in purely passive touch. We do this by showing that the array of tactile receptive fields in the skin, and appropriately relayed to the cortex, may contain the same basic informational building (...) blocks that a creature navigating around its environment uses to build up a perception of space. We illustrate this point with preliminary evidence that perception of spatiotemporal patterns on the human skin shows some of the same features as spatial navigation in animals. We argue (a) that the receptor array defines a ‘tactile field’, (b) that this field exists in a minimal form in ‘skin space’, logically prior to any transformation into bodily or external spatial coordinates, and (c) that this field supports tactile perception without integration of concurrent proprioceptive or motor information. The basic cognitive elements of space perception may begin at lower levels of neural and perceptual organisation than previously thought. (shrink)

This chapter distinguishes between two kinds of ordinary multisensory experience that go beyond mere co-consciousness of features (e.g., the experience that results from concurrently hearing a sound in the hallway and seeing the cup on the table). In one case, a sensory experience in one modality creates a perceptual demonstrative to whose referent qualities are attributed in another sensory modality. For example, when you hear someone speak, auditory experience attributes audible qualities to a seen event, a person’s speaking motions. (...) The second kind of multisensory experience attributes features experienced in several sensory modalities to one and the same object via a process of amodal perceptual integration, i.e., integration that occurs separately from processing within the individual sensory modalities. Multisensory experiences arising from holding and seeing a tomato or from seeing the Indian curry boil and smelling it are examples of the second kind of multisensory experience. At the end of the chapter we look at synesthesia, a kind of atypical multisensory experience, and argue that one version of this phenomenon may be able to shed light on the neural mechanism underlying amodally integrated multisensory experience. (shrink)

The human eyes and brain, which have finite boundaries, create a ‘‘virtual’’ space within our central nervous system that interprets and perceives a space that appears boundless and infinite. Using insights from studies on the visual system, we propose a novel fast processing mechanism involving the eyes, visual pathways, and cortex where external vision is imperceptibly processed in our brain in real time creating an internal representation of external space that appears as an external view. We introduce (...) the existence of a three-dimension default space consisting of intrapersonal body space that serves as the framework where visual and non-visual sensory information is sensed and experienced. We propose that the thalamus integrates processed information from corticothalamic feedback loops and fills-in the neural component of 3D default space with an internal visual representation of external space, leading to the experience of visual consciousness. This visual space inherently evades perception so we have introduced three easy clinical tests that can assist in experiencing this visual space. We also review visual neuroanatomical pathways, binocular vision, neurological disorders, and visual phenomenon to elucidate how the representation of external visible space is recreated within the mind. (shrink)

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: What is the purpose of multisensory integration?

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: Is language processing a special kind of multisensory integration?

This is the editors' Introduction to a special issue of the journal, Multisensory Research. European philosophers of the modern period found multisensory perception to be impossible because they thought that perceptual ideas are defined by how they are experienced. Under this conception, the individual modalities are determinables of ideas—just as colour is a determinable that embraces red and blue, so also the visual is a determinable that embraces colour and (visually experienced) shape. Since no idea is experienced as, (...) for example, both visual and auditory, there can be no such thing as audiovisual perception. This conception of modality is not directly contested, but a variety of perceptual phenomena are listed that could raise interesting questions if treated as multimodal in origin. (shrink)

The visuospatial system integrates inner and outer functional processes, organizing spatial, temporal, and social interactions between the brain, body, and environment. These processes involve sensorimotor networks like the eye–hand circuit, which is especially important to primates, given their reliance on vision and touch as primary sensory modalities and the use of the hands in social and environmental interactions. At the same time, visuospatial cognition is intimately connected with memory, self-awareness, and simulation capacity. In the present article, we review issues associated (...) with investigating visuospatial integration in extinct human groups through the use of anatomical and behavioral data gleaned from the paleontological and archaeological records. In modern humans, paleoneurological analyses have demonstrated noticeable and unique morphological changes in the parietal cortex, a region crucial to visuospatial management. Archaeological data provides information on hand–tool interaction, the spatial behavior of past populations, and their interaction with the environment. Visuospatial integration may represent a critical bridge between extended cognition, self-awareness, and social perception. As such, visuospatial functions are relevant to the hypothesis that human evolution is characterized by changes in brain–body–environment interactions and relations, which enhance integration between internal and external cognitive components through neural plasticity and the development of a specialized embodiment capacity. We therefore advocate the investigation of visuospatial functions in past populations through the paleoneurological study of anatomical elements and archaeological analysis of visuospatial behaviors. (shrink)

This chapter examines how our sense modalities interact in the perception of persistence. The chapter concentrates on two questions. The first concerns perceptual processing—do perceptual computations of object persistence ever integrate and compute over representations from more than one modality? It argues that this question should be answered affirmatively. The second question concerns perceptual experience—do experiences of object persistence ever exhibit a constitutively multisensory phenomenal character, or is the phenomenology of object persistence always uniquely associated with just one modality? (...) The chapter argues that the available evidence underdetermines the answer to this question, but suggests ways it might be empirically resolved. (shrink)

This chapter critically assesses recent arguments that acquiring the ability to categorize an object as belonging to a certain high-level kind can cause the relevant kind property to be represented in visual phenomenal content. The first two arguments, developed respectively by Susanna Siegel (2010) and Tim Bayne (2009), employ an essentially phenomenological methodology. The third argument, developed by William Fish (2013), by contrast, is supported by an array of psychophysical and neuroscientific findings. I argue that while none of these arguments (...) ultimately proves successful, there is a substantial body of empirical evidence that information originating outside the visual system can nonetheless modulate the way an object’s low-level attributes visually appear. Visual phenomenal content, I show, is not only significantly influenced by crossmodal interactions between vision and other exteroceptive senses such as touch and audition, but also by interactions between vision and non-perceptual systems involved in motor planning and construction of the proprioceptive body-image. (shrink)

What if a blind person could 'see' with her ears? Thanks to Sensory Substitution Devices (SSDs), blind people now have access to out-of-reach objects, a privilege reserved so far for the sighted. In this paper, we show that the philosophical debates have fundamentally been mislead to think that SSDs should be fitted among the existing senses or that they constitute a new sense. Contrary to the existing assumption that they get integrated at the sensory level, we present a new thesis (...) according to which they are not sensory, and get vertically integrated on the top of existing sensory abilities, from which they should be theoretically distinguished. (shrink)

We perceive in many ways. But several dubious presuppositions about the senses mask this diversity of perception. Philosophers, scientists, and engineers alike too often presuppose that the senses (vision, audition, etc.) are independent sources of information, perception being a sum of these independent contributions. We too often presuppose that we can generalize from vision to other senses. We too often presuppose that vision itself is best understood as a passive receptacle for an image thrown by a lens. In this essay (...) we illustrate how reflection on results from the cognitive sciences undermine these (and many other) traditional presuppositions. Our illustration situates the remaining essays in the volume, Perception and its Modalities, which further extend the case against various traditional presuppositions, and offer alternatives ways to understand the senses and their role in perception. While many of the essays in this volume represent competing views and draw on different fields, from conceptual analysis to engineering, most contributors believe that to understand perception properly, we need to treat as foundational the idea that the senses work together. From that agreement, new paradigms for theorizing about perception begin to emerge. (shrink)

The role of the physiological processes involved in human vision escapes clarification in current literature. Many unanswered questions about vision include: 1) whether there is more to lateral inhibition than previously proposed, 2) the role of the discs in rods and cones, 3) how inverted images on the retina are converted to erect images for visual perception, 4) what portion of the image formed on the retina is actually processed in the brain, 5) the reason we have an after-image with (...) antagonistic colors, and 6) how we remember space. This theoretical article attempts to clarify some of the physiological processes involved with human vision. The global integration of visual information is conceptual; therefore, we include illustrations to present our theory. Universally, the eyeball is 2.4 cm and works together with membrane potential, correspondingly representing the retinal layers,photoreceptors, and cortex. Images formed within the photoreceptors must first be converted into chemical signals on the photoreceptors’ individual discs and the signals at each disc are transduced from light photons into electrical signals. We contend that the discs code the electrical signals into accurate distances and are shown in our figures. The pre-existing oscillations among the various cortices including the striate and parietal cortex,and the retina work in unison to create an infrastructure of visual space that functionally ‘‘places” the objects within this ‘‘neural” space. The horizontal layers integrate all discs accurately to create a retina that is pre-coded for distance. Our theory suggests image inversion never takes place on the retina,but rather images fall onto the retina as compressed and coiled, then amplified through lateral inhibition through intensification and amplification on the OFF-center cones. The intensified and amplified images are decompressed and expanded in the brain, which become the images we perceive as external vision. (shrink)

Each of our sensory modalities—vision, touch, taste, etc.—works on a slightly different timescale, with differing temporal resolutions and processing lag. This raises the question of how, or indeed whether, these sensory streams are co-ordinated or ‘bound’ into a coherent multisensory experience of the perceptual ‘now’. In this paper I evaluate one account of how temporal binding is achieved: the temporal windows hypothesis, concluding that, in its simplest form, this hypothesis is inadequate to capture a variety of multisensory phenomena. (...) Rather, the evidence suggests the existence of a more complex temporal structure in which multiple overlapping windows support distinct functional mechanisms. To aid in the precise formulation of such views, I propose a taxonomy of temporal window types and their characteristics that in turn suggests promising avenues for future empirical and philosophical research. I conclude by examining some philosophical implications of multi-window models for the metaphysics of perception and perceptual experience more generally. (shrink)

In crossmodal identification, a subject token identifies an item perceived in one sensory modality with an item perceived in another sensory modality. Does crossmodal identification always occur in cognition, or does crossmodal identification sometimes take place in perception? This paper argues that crossmodal identification occurs in cognition, and not in perception. Nevertheless, multisensory perception is not unalive to crossmodal identity. Experimental evidence demonstrates that perception is differentially sensitive to the identity of individuals presented to distinct senses. Such sensitivity enhances (...) recognition and improves action. This approach relies on distinguishing crossmodal identification from perceiving crossmodal identity. Perception registers crossmodal identity, but crossmodal identification as such belongs to thought. (shrink)

In this chapter, data concerning the development of principal aspects of vision is reviewed. First, the development of colour vision and luminance perception is discussed. Relevant data accumulated so far indicates that perception of colour and luminance is present by 6-9 months of age. The presence of typical color illusions at this age suggests that the phenomenal character of color experience is comparable to that of adults well before the first birthday. Thus it seems plausible that color perception develops on (...) the grounds of genetically preprogrammed maturation, in which perceptual learning and plasticity play a limited role. This claim also seems to be supported by case studies of newly sighted patients. On the other hand, perceptual integration of edges and forms in the visual environment as well as the development of binocular vision, and the perception of ambiguous figures seem to depend crucially on early perceptual learning. Both developmental and clinical data indicate a more significant involvement of perceptual learning in such mid-level and higher level perceptual phenomena. (shrink)

Touch is standardly taken to be a proximal sense, principally constituted by capacities to detect proximal pressure and thermal stimulation, and contrasted with the distal senses of vision and audition. It has, however, recently been argued that the scope of touch extends beyond proximal perception; touch can connect us to distal objects. Hence touch generally should be thought of as a connection sense. In this paper, I argue that whereas pressure perception is a connection sense, thermal perception is not. Thermal (...) perception is a proximal sense distinct from touch. One significant consequence of this is that it motivates an alternative explanation of how we detect the thermal properties of the things we touch and what they are. (shrink)

Block (Trends Cogn Sci 7:285–286, 2003) and Prinz (PSYCHE 12:1–19, 2006) have defended the idea that SSD perception remains in the substituting modality (auditory or tactile). Hurley and Noë (Biol Philos 18:131–168, 2003) instead argued that after substantial training with the device, the perceptual experience that the SSD user enjoys undergoes a change, switching from tactile/auditory to visual. This debate has unfolded in something like a stalemate where, I will argue, it has become difficult to determine whether the perception acquired (...) through the coupling with an SSD remains in the substituting or the substituted modality. Within this puzzling deadlock two new approaches have been recently suggested. Ward and Meijer (Conscious Cogn 19:492–500, 2010) describe SSD perception as visual-like but characterize it as a kind of artificially induced synaesthesia. Auvray et al. (Perception 36:416–430, 2007) and Auvray and Myin (Cogn Sci 33:1036–1058, 2009) suggest that SSDs let their users experience a new kind of perception. Deroy and Auvray (forthcoming) refine this position, and argue that this new kind of perception depends on pre-existing senses without entirely aligning with any of them. So, they have talked about perceptual experience in SSDs as going "beyond vision". In a similar vein, MacPherson (Oxford University Press, New York, 2011a) claims that “if the subjects (SSD users) have experiences with both vision-like and touch-like representational characteristics then perhaps they have a sense that ordinary humans do not” (MacPherson in Oxford University Press, New York, 2011a, p. 139). (shrink)

The sense of touch provides us knowledge of two kinds of events. Tactile sensation (T) makes us aware of events on or just below the skin; haptic perception (H) gives us knowledge of things outside the body with which we are in contact. This paper argues that T and H are distinct experiences, and not (as some have argued) different aspects of the same touch-experience. In other words, T ≠ H. Moreover, H does not supervene on T. Secondly: In T, (...) we are aware of immanent, phenomenal qualities; in H, we come to know of transcendent qualities in things that exist independently of ourselves. Finally: T is non-spatial; it is indexed by parts of the body, but not by position in space. H, by contrast, is spatial. This brings to mind Kant’s contention that things are presented as existing objectively when they are represented spatially. (shrink)

This paper argues that a common form of representationalism has trouble accommodating empirical findings about visual space perception. Vision science tells us that the visual system systematically gives rise to different experiences of the same spatial property. This, combined with a naturalistic account of content, suggests that the same spatial property can have different veridical looks. I use this to argue that a common form of representationalism about spatial experience must be rejected. I conclude by considering alternatives to this (...) view. (shrink)

In the September 2020 edition of Perception, Alan Gilchrist published an editorial entitled “The Integrity of Vision” (Gilchrist, 2020). In it, Gilchrist critiques motivated perception research. His main points are as follows: (1) Motivated perception is compromised by experimental demand: Results do not actually show motivated perception but instead reflect subjects’ desires to comply with inferred predictions. (2) Motivated perception studies use designs that make predictions obvious to subjects. These transparent designs conspire with experimental demand to yield confirmatory but compromised (...) results. (3) Motivated perception research lacks guiding theory and cannot explain what appear to be contradictory results. (4) Motivated perception presents an unsupportable assault upon the impermeability of perception. The present commentary responds to these four assertions. (shrink)

We can discern two opposing viewpoints regarding synesthesia. According to the first, it is an oddity, an outlier, or a disordered condition. According to the second, synesthesia is pervasive, driving creativity, metaphor, or language itself. Which is it? Ultimately, I favor the first perspective, according to which cross-sensory synesthesia is an outlying condition. But the second perspective is not wholly misguided. My discussion has three lessons. First, synesthesia is just one of a variety of effects in which one sense modality (...) causally impacts and reshapes experience associated with another. These effects are utterly common. However, due to their unfamiliarity, and to their conflict with a widespread conception of the role of the senses in perception and perceptual experience, until recently they have been surprising. Second, synesthesia nevertheless must be distinguished from other inter-modal effects that lead to misperception, such as crossmodal illusions. Third, synesthesia also may be distinguished from the potentially much broader class of synesthetic effects, which could be common across the population and within individuals. (shrink)

It seems that there are important differences concerning the way in which space itself is presented in visual and tactile modalities. In the case of vision, it is usually accepted that visual objects are experienced as located in a visual field. However, it is controversial whether similar field-like characteristics can be attributed to the space in which tactile entities are experienced to be located. The paper investigates whether postulating the presence of a tactile field is justified. I argue (...) that the answer is both ‘yes’ and ‘no’ due to the dual nature of touch: touch is both an interoceptive modality that presents states of one’s body and an exteroceptive modality that presents external entities. More specifically, the interoceptive tactile space has a character of a spatial field. On the other hand, the exteroceptive tactile space does not have characteristics necessary for ascribing the field-status. (shrink)

This is an excerpt of a report that highlights and explores five questions which arose from The Unity of Consciousness and Sensory Integration conference at Brown University in November of 2011. This portion of the report explores the question: Is the mechanism of sensory integration spatio-temporal?

How many senses do humans possess? Five external senses, as most cultures have it—sight, hearing, touch, smell, and taste? Should proprioception, kinaesthesia, thirst, and pain be included, under the rubric bodily sense? What about the perception of time and the sense of number? Such questions reduce to two. 1. How do we distinguish a sense from other sorts of information-receiving faculties? 2. By what principle do we distinguish the senses? Aristotle discussed these questions in the De Anima. H. P. Grice (...) revived them in 1967. More recently, they have taken on fresh interest as a result of a collection of essays edited by Fiona Macpherson. This entry reviews some approaches to these questions and advances some new ideas for the reader’s consideration. It proposes that the senses constitute an integrated learning system, membership in which answers question 1. It also proposes that the modalities can be distinguished from one another in two ways, by the means of information pick-up and by the kinds of activity that a perceiver undertakes to make use of them. (shrink)

This is a book about the metaphysics of perception and discusses touch, audition, and vision. Though primarily concerned with the nature of perception, it draws heavily from the history of philosophy of perception, and connects the concerns of analytical and continental philosophers.

The discovery of so-called ‘mirror neurons’ - found to respond both to own actions and the observation of similar actions performed by others - has been enormously influential in the cognitive sciences and beyond. Given the self-other symmetry these neurons have been hypothesized as underlying a ‘mirror mechanism’ that lets us share representations and thereby ground core social cognitive functions from intention understanding to linguistic abilities and empathy. I argue that mirror neurons are important for very different reasons. Rather than (...) a symmetric ubiquitous or context- independent mechanism, I propose that these neurons are part of broader sensorimotor circuits, which help us navigate and predict the social affordance space that we meet others in. To develop both the critical and positive project I analyze the interpretive choices and the debate surrounding the mirror neuron research and show how the field is marred by highly questionable assumptions about respectively motor and social cognition. The discovery of mirror neurons - and the sensorimotor circuits of which these neurons are a part – actually empirically challenge many of these tacit assumptions. Findings of sensorimotor goal representations at levels of abstraction well beyond actual sensory information and kinetic movements challenge the idea of motor cognition as primarily output production. Additionally, the focus on 3rd person mindreading of hidden mental states is misguiding the field of social cognition. Much ‘mind-reading’ seems rooted in sensorimotor representations and a developmentally primary 2nd person understanding of actions and the mental lives of others, which precisely breaks the assumed dichotomy between mind and behavior. I propose a Social Affordance model where parallel fronto-parietal sensorimotor circuits support representations not just of other people’s actions but of the overall social affordance space. It is a process that monitors concrete goals and teleological possibilities that the environment affords respectively oneself and other present agents. With this model I hypothesize that the complex spectrum of sensorimotor integrations are indeed essential not only to normal action choice calibration but also to social cognitive abilities, as the sensorimotor teleological representations let us relate to others and understand their action choices in a shared pragmatic and intentional context. (shrink)

Long-standing neglect of the chemical senses in the philosophy of perception is due, mostly, to their being regarded as ‘lower’ senses. Smell, taste, and chemically irritated touch are thought to produce mere bodily sensations. However, empirically informed theories of perception can show how these senses lead to perception of objective properties, and why they cannot be treated as special cases of perception modelled on vision. The senses of taste, touch, and smell also combine to create unified perceptions of flavour. The (...) nature of these multimodal experiences and the character of our awareness of them puts pressure on the traditional idea that each episode of perception goes one or other of the five senses. Thus, the chemical senses, far from being peripheral to the concerns of the philosophy of perception, may hold important clues to the multisensory nature of perception in general. (shrink)

Common everyday materials such as textiles, foodstuffs, soil or skin can have complex, mutable and varied appearances. Under typical viewing conditions, most observers can visually recognize materials effortlessly, and determine many of their properties without touching them. Visual material perception raises many fascinating questions for vision researchers, neuroscientists and philosophers, yet has received little attention compared to the perception of color or shape. Here we discuss some of the challenges that material perception raises and argue that further philosophical thought should (...) be directed to how we see materials. (shrink)

Conspectus of part of John R. Smythies' Analysis of Perception (1956). It presents a summary of his ideas on phenomenal space – the space of one’s imagination, dreams, psychedelic experiences, somatic sensations, visions, hynagogia, etc. – and its relation to physical space.

According to representionalists, qualia-the introspectible properties of sensory experience-are exhausted by the representational contents of experience. Representationalists typically advocate an informational psychosemantics whereby a brain state represents one of its causal antecedents in evolutionarily determined optimal circumstances. I argue that such a psychosemantics may not apply to certain aspects of our experience, namely, our experience of space in vision, hearing, and touch. I offer that these cases can be handled by supplementing informational psychosemantics with a procedural psychosemantics whereby a (...) representation is about its effects instead of its causes. I discuss conceptual and empirical points that favor a procedural representationalism for our experience of space. (shrink)

The problem of amodal perception is the problem of how we represent features of perceived objects that are occluded or otherwise hidden from us. Bence Nanay (2010) has recently proposed that we amodally perceive an object's occluded features by imaginatively projecting them into the relevant regions of visual egocentric space. In this paper, I argue that amodal perception is not a single, unitary capacity. Drawing appropriate distinctions reveals amodal perception to be characterized not only by mental imagery, as (...) Nanay suggests, but also by genuinely visual representations as well as beliefs. I conclude with some brief remarks on the role of object-directed bodily action in conferring a sense of unseen presence on an object's occluded features. (shrink)

Pictures are 2D surfaces designed to elicit 3D-scene-representing experiences from their viewers. In this essay, I argue that philosophers have tended to underestimate the relevance of research in vision science to understanding the nature of pictorial experience. Both the deeply entrenched methodology of virtual psychophysics as well as empirical studies of pictorial space perception provide compelling support for the view that pictorial experience and seeing face-to-face are experiences of the same psychological, explanatory kind. I also show that an empirically (...) informed account of pictorial experience provides resources to develop a novel, resemblance-based account of depiction. According to what I call the deep resemblance theory, pictures work by presenting virtual models of objects and scenes in phenomenally 3D, pictorial space. (shrink)

This paper examines Helmholtz's attempt to use empirical psychology to refute certain of Kant's epistemological positions. Particularly, Helmholtz believed that his work in the psychology of visual perception showed Kant's doctrine of the a priori character of spatial intuition to be in error. Some of Helmholtz's arguments are effective, but this effectiveness derives from his arguments to show the possibility of obtaining evidence that the structure of physical space is non-Euclidean, and these arguments do not depend on his theory (...) of vision. Helmholtz's general attempt to provide an empirical account of the "inferences" of perception is regarded as a failure. (shrink)

How should we think about the role of visual spatial awareness in perception and perceptual knowledge? A common view, which finds a characteristic expression in Kant but has an intellectual heritage reaching back farther than that, is that an account of spatial awareness is fundamental to a theory of experience because spatiality is the defining characteristic of “outer sense”, of our perceptual awareness of how things are in the parts of the world that surround us. A natural counterpart to this (...) idea is to treat self-consciousness as residing in a kind of sense that is fundamentally “inner”, such as introspection or whatever else gives one privileged access to his own mental states as well as the proprioceptive and kinesthetic awareness of bodily position. This division is compatible, of course, with the idea that inner sense provides an awareness of a distinctive kind of “body space”, but it treats that as importantly different from the awareness of the worldly space around one. -/- In contrast to such a picture, this dissertation proposes an account of visual spatial awareness according to which it is no less a source of self-consciousness than of the awareness of the objects around us, and an account of self-awareness in which visual experience is essentially implicated. I begin by arguing that we should think of visual spatial awareness not as necessary for the individuation of visual sensations but rather as an essential element in the awareness of an experientially objective world. In the subsequent chapters, I argue that in being visually aware of the egocentric positions of the worldly objects around us we are often aware also of our own spatial locations with respect to them, and that the visual experience of the world around one and one’s own situation in it is often an essential component in the knowledge that a human agent will have of his own intentional actions. (shrink)

According to a common opinion, human olfactory experiences are significantly different from human visual experiences. For instance, olfaction seems to have only rudimentary abilities to represent space; it is not clear whether olfactory experiences have any mereological structure; and while vision presents the world in terms of objects, it is a matter of debate whether there are olfactory object-representations. This paper argues that despite these differences visual and olfactory experiences share a hierarchical subject/property structure. Within this structure, olfactorily experienced (...) odours and visual objects have the same status: they are primary subjects which unify other represented elements into perceptual units. (shrink)