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Smell images and the flavour system in the human brain


Flavour perception is one of the most complex of human behaviours. It involves almost all of the senses, particularly the sense of smell, which is involved through odour images generated in the olfactory pathway. In the human brain, the perceptual systems are closely linked to systems for learning, memory, emotion and language, so distributed neural mechanisms contribute to food preference and food cravings. Greater recognition of the role of the brain's flavour system and its connection with eating behaviour is needed for a deeper understanding of why people eat what they do, and to generate better recommendations about diet and nutrition.

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Figure 1: Odour images in the olfactory glomerular layer.
Figure 2: The dual olfactory system.
Figure 3: The human brain flavour systems that evaluate and regulate food intake.


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Research in my laboratory is supported by the National Institutes of Health National Institute for Deafness and Other Communicative Disorders, and by the Human Brain Project. I thank M. L. Pelchat, E. T. Rolls, D. Small, L. Bartoshuk, T. Acree, F. Q. Xu and V. Duffy for valuable advice.

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Correspondence to Gordon M. Shepherd.

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Shepherd, G. Smell images and the flavour system in the human brain. Nature 444, 316–321 (2006).

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