Multisensory Consciousness and Synesthesia

Abstract

This chapter argues that the phenomenology of one type of multisensory experience that goes beyond mere co-consciousness derives exclusively from the individual sensory modalities. Call this type of experience "modal multisensory experience". The chapter also argues that another kind of normal multisensory experience that goes beyond mere co-consciousness requires a different treatment. The second type of experience is one where the phenomenology is distinctively multisensory and perceptual, yet amodally integrated. Call this type of experience "amodal sensory experience". The chapter looks at the case of synesthesia–a type of atypical integration in which different sensory streams are bound together in unusual ways, for instance, sounds may be bound together with color. It then argues that some forms of synesthesia may be helpful in investigating the neural mechanism underlying amodal multisensory binding. The chapter compares certain types of synesthesia to amodal multisensory perception and argues that these types of synesthesia may shed light on amodal integration.