The neurocognitive bases of human multimodal food perception: sensory integration.

This review addresses a fundamental neuroscientific question in food perception: how multimodal features of food are integrated. Much research and conceptualization has emerged related to multisensory integration in vision, audition and somatosensation, while it remains poorly understood and researched within the chemical and mouth feel senses. This review aims to bridge this gap. We discuss the main concepts in the fields of auditory, visual and somatosensory multisensory integration and relate them to oral-sensory (gustatory and somatosensory) and olfactory (orolfactory) interactions. We systematically review the psychophysical literature pertaining to intra- and intermodal interactions related to food perception, while making explicit distinctions between peripheral and central interactions. As the neural bases of crossmodal orolfaction currently are poorly understood, we introduce several plausible neuroscientific models, which provide a framework for further neuroscientific exploration in this area. We are guided by a new meta-analysis of the odor-taste neuroimaging literature, as well as by single-unit, anatomical and psychophysical studies. Finally, we propose strong involvement of recurrent neural networks in multisensory integration and make suggestions for future research.