Casey O'Callaghan

Vision has dominated philosophical thinking about perceptual experience and the nature of its objects. Color has long been the focus of debates about the metaphysics of sensible qualities, and philosophers have struggled to articulate the conditions on the visual experience of mind-independent objects. With few notable exceptions, "visuocentrism" has shaped our understanding of the nature and functions of perception, and of our conception of its objects. The predominant line of thought from the early modern era to the present is that, in the philosophically interesting respects, as things are with vision, so they are with hearing, touch, olfaction, and the rest. A closely related line of thought has been particularly strong in the case of the secondary qualities

Cross-modal perceptual illusions occur when a stimulus to one modality impacts perceptual experience associated with another modality. Unlike synaesthesia, cross-modal illusions are intelligible as results of perceptual strategies for dealing with sensory stimulation to multiple modalities, rather than as mere quirks. I argue that understanding cross-modal illusions reveals an important flaw in a widespread conception of the senses, and of their role in perceptual experience, according to which understanding perception and perceptual experience is a matter of assembling independently viable stories about vision, audition, olfaction, and the rest.

I argue that sounds are best conceived not as pressure waves that travel through a medium, nor as physical properties of the objects ordinarily thought to be the sources of sounds, but rather as events of a certain kind. Sounds are particular events in which a surrounding medium is disturbed or set into wavelike motion by the activities of a body or interacting bodies. This Event View of sounds provides for a uni- ?ed perceptual account of several pervasive sound phenomena, including transmission through barriers, constructive and destructive interference, and echoes

Recent work on non-visual modalities aims to translate, extend, revise, or unify claims about perception beyond vision. This paper presents central lessons drawn from attention to hearing, sounds, and multimodality. It focuses on auditory awareness and its objects, and it advances more general lessons for perceptual theorizing that emerge from thinking about sounds and audition. The paper argues that sounds and audition no better support the privacy of perception’s objects than does vision; that perceptual objects are more diverse than an exclusively visual perspective suggests; and that multimodality is rampant. In doing so, it presents an account according to which audition affords awareness as of not just sounds, but also environmental happenings beyond sounds.

Listening to speech in a language you know differs phenomenologically from listening to speech in an unfamiliar language, a fact often exploited in debates about the phenomenology of thought and cognition. It is plausible that the difference is partly perceptual. Some contend that hearing familiar language involves auditory perceptual awareness of meanings or semantic properties of spoken utterances; but if this were so, there must be something distinctive it is like auditorily to perceptually experience specific meanings of spoken utterances. However, an argument from homophony shows that auditory experiences do not resolve differences in meaning not marked by differences in sound. I propose an alternative explanation of the perceptual phenomenal difference in terms of perceptual awareness of language-specific but non-semantic features

Object perception deploys a suite of perceptual capacities that constrains attention, guides reidentification, subserves recognition, and anchors demonstrative thought. Objects for perception—perceptual objects—are the targets of such capacities. Characterizing perceptual objects for multisensory perception faces two puzzles. First is the diversity of objects across sensory modalities. Second is the unity of multisensory perceptual objects. This paper resolves the puzzles. Objects for perception are structured mereologically complex individuals. Perceptual objects are items that bear perceptible features and have perceptible parts arranged to form a unified whole. This circumscribes the targets of object perception where neutral talk concerning intentional objects and objects of perception cannot. Nonetheless, it is more permissive than identifying perceptual objects with material bodies, which excludes too much and leans too heavily on vision. The account thus is tailored to capture the role of objects in perception beyond vision: tactual, auditory, and olfactory objects are individuals with differing structures. Its flexibility also enables the account to accommodate shared objects for multisensory perception: multisensory perceptual objects are mereologically complex individuals with hybrid structure. For instance, one can bimodally perceive a common whole with parts accessible to one but not both modalities. Each sense provides a partial perspective on a complex whole that is perceptible through the coordinated use of multiple senses. Understanding perceptual objects as structured mereologically complex individuals thus provides a theoretically useful notion of an object for multisensory perception that resolves the puzzles of diversity and of unity

Philosophers and cognitive scientists of perception by custom have investigated individual sense modalities in relative isolation from each other. However, perceiving is, in a number of respects, multimodal. The traditional sense modalities should not be treated as explanatorily independent. Attention to the multimodal aspects of perception challenges common assumptions about the content and phenomenology of perception, and about the individuation and psychological nature of sense modalities. Multimodal perception thus presents a valuable opportunity for a case study in mature interdisciplinary cognitive science. This chapter aims to raise these issues against the background of unimodal approaches in the study of perception. It presents some of the central empirical findings concerning multimodality, and it explains the philosophical implications of these findings. Foremost, it aims to encourage and open avenues for future research.

My thesis is that perceptual awareness is richly multisensory. I argue for this conclusion on the grounds that certain forms of multisensory perceptual experience are incompatible with the claim that each aspect of a perceptual experience is associated with some specific sensory modality or another. First, I explicate what it is for some feature of a conscious perceptual episode to be modality specific. Then, I argue based on philosophical and experimental evidence that some novel intermodal features are perceptible only through the coordinated use of multiple senses. I appeal to cases that involve consciously perceptible feature instances and feature types that could not be perceptually experienced through the use of individual sense modalities working on their own or simply in parallel and co-consciously. Finally, I offer an account of how to type perceptual experiences by modality that makes room for richly multisensory experiences