The Multisensory Mouth: An investigation into the somatosensory, olfactory and gustatory processes driving oral behaviours

The research to be undertaken will focus on a fuller understanding and characterisation of the sensory, perceptual, behavioural and emotional (like/dislike) mechanisms engaged during oral multisensory processing. This will involve both 'bottom-up' and 'top-down' approaches. The former will study the function and interactions of multisensory oral systems (touch, temperature, pain, taste, chemosensory, olfactory) engaged in oral behaviours, and the latter with the perceptual, cognitive and emotional systems that interpret and influence these multisensory processes, and here we expect vision and hearing to contribute to, for example, flavour perception (see these papers for more examples of how the oral senses merge with vision and hearing - Levitan et al, 2008; Morot et al, 2001; North & Hargeaves, 2008; Oberfeld et al, 2009; Parr et al, 2003;.Rozin, 1982)
Research.
Research questions:
1. Does multisensory integration differ between superfeelers/tasters and non -feelers/tasters?
2. What is the impact of Taster Status (a genetic polymorphism) on multisensory processing?
3. Can the rules of cross-modal perception such as superadditivity, sensory dominance, ventriloquism etc inform on complex oro-sensory percepts such as dryness, mouthfeel?
4. To what extent do individual differences in responses to oral stimuli reflect contextual (top-down) versus peripheral (bottom-up) sensory processing?

Research methods:
1. Psychophysics and quantitative sensory testing
2. Implicit behavioural measures of multisensory perception
3. Genetic polymorphisms and population segmentation
4. Covert measures of emotion - psychophysiology - EMG, skin conductance, heart rate
5. Neuroimaging - fMRI
Scope: The thesis will examine how multisensory interactions drive oro-sensory perception. The effects of oral care products on these processes will be studied from a cross-modal perspective, as well as the influence of more cognitive manipulations.