The Rethinking the Senses team is delighted that the first workshop of the second phase of the project will be hosted as a symposium at the 22nd Annual meeting of the European Society for Philosophy & Psychology, to be held at the University of Messina, Noto from 16-19 September 2014.
For more information on the ESPP, including how to register, please visit their website.
Two sessions will be presented as part of this symposium, with the second session followed by a 30-minute panel discussion. (Download Abstracts)
Session 1: Perspectives on audio-visual interactions
Until recently research into sensory perception has focused on unisensory perception, and, in particular, on vision. There has, however, been mounting awareness of the fact that our perceptual systems are presented with multiple different sensory signals at any one time. This allows for the possibility of multisensory interactions, where input from one sensory system has an influence on what one perceives in another modality. So, for example, visual input can influence auditory perception, a well-known example of this being the Ventriloquism Effect in which there is visual capture of auditory location. So too, auditory input can exert an influence over visual perception.
For audio-visual interactions to occur the perceptual system must solve the problem of ascertaining which signals pertain to the same object, and hence should be combined or bound together, and which signals pertain to different objects, and hence should be segregated or kept apart. This is the crossmodal binding problem. There is evidence that spatial, temporal and semantic congruence can influence crossmodal binding and hence support audio-visual interactions. But there has also been a suggestion that there are other kinds of matches—crossmodal correspondences between what appear to be different kinds of stimulus features such as pitch & spatial elevation and loudness & brightness—that also influence crossmodal binding. One important question to consider, in understanding the conditions necessary for audio-visual interactions, is whether stimulus features are in fact non-redundant in the way we might intuitively take them to be. This symposium will examine this issue from different psychological, developmental, and philosophical perspectives.
Ophelia Deroy and Merle Fairhurst – The space of music: pitch, and other auditory dimensions
Yi-Chuan Chen, Gert Westermann, and Charles Spence – Development of audiovisual associations: nature or nurture?
Malika Auvray and Ophelia Deroy, Irène Fasiello and Vincent Hayward – Crossmodal correspondences between pitch and tactile movement in sighted, early, and late blind people
Matthew Nudds and Alisa Mandrigin – Auditory perception and audiovisual interactions
Session 2 – Individuating the Senses
Fiona Macpherson and Keith Wilson – Orthonasal and Retronasal Olfaction: One Sense or Two?
We discuss problems for the standard four ways of individuating the senses using the criteria of representation, phenomenal character, proximal stimulus and sense organ. We argue that if we reject a sparse view of how many senses there are or could be, according to which there is a small number of discrete senses, then one can use these criteria all together to form a fine-grained taxonomy of types of senses. We then examine the implications of such an approach for individuating the smell, which has been labelled a ‘dual sense’ by Rozin (1982), following Gibson (1968), due to its role in identifying externally located objects and contributing to the experience of flavour in the mouth. We review the empirical evidence for the existence of dual olfactory type- or token-senses, and the implications of this issue for creating a taxonomy of the senses and multisensory interactions more generally.
Ophelia Deroy and Barry Smith (in absentia) – The Place of Olfaction in Conscious Experience
What role does olfaction play in our conscious lives? Smell seems to go missing in everyday experience: many people claim to be unaware of smells until they deliberately sniff at things in the immediate environment. On the other hand we smell because we breathe and we are constantly bombarded by thousands of volatile molecules, and these odours can have an impact on our mood, behaviour and food choices. So are smells in consciousness though we are not aware of them (or of smelling things); do they go in and out of consciousness dependent on a shifting threshold; or are they unrecognised as such because they provide a background to consciousness? Answering these questions has consequences for how we should understand the modality (or modalities) of olfaction.
Colin Blakemore and Yuanyuan Zhao – What makes seeing different from hearing?
One of the reasons why philosophers are exercised about the number and individuation of human senses is the distinctive subjective signature of each of our major senses. Consider vision: we know from single-neuron recording in animals and neuroimaging studies in humans that different aspects of visual experience (form, colour, motion, depth etc) are processed by different classes of neurons, even in different parts of the cerebral cortex. Yet they are all indubitably visual in their ‘feel’. Although these various components of a visual experience differ in subjective character, they share the quality of being visual – never (or so it feels) to be confused with the experiences that constitute hearing, touch, smell etc.
We are interested in the neural basis and the certainty of perceptual distinction between modalities. We are testing whether the ability to distinguish visual and auditory stimuli is maintained close to the threshold of forced-choice detection, where stimuli are not sufficiently intense reliably to trigger conscious experiences.
What could be the neural representation of subjective modalities? Given the interest in the ‘neural correlate of consciousness’ it is surprising that this question has attracted little interest from neuroscientists. We consider three possible neurophysiological accounts of modality distinction:
- The modality of experience is simply determined by which particular neurons carry the signals. For instance, Ewald Hering proposed that an innate ‘retinal local sign’ determines the perceived spatial location of a visual stimulus.
- The modality is encoded in the temporal pattern of impulses in sensory neurons. Johannes Müller’s original formulation of the Law of Specific Nerve ‘Energies’ is of this type.
- The modality experienced is somehow imposed on perceptual representations by a ‘top-down’ process.
We shall review these hypotheses. Unfortunately there is contrary evidence for each of them.