Olfaction: Central Processing

Abstract

Olfactory receptor neurons in the nasal epithelium detect a huge variety of airborne chemicals (termed ‘odorants’) and encode information about these stimuli in the form of action potentials. This code is then transmitted to the brain, where patterns of neural activity represent the identity, concentration and temporal dynamics of the odorants. Neural processing of olfactory information at multiple levels in the brain mediates odour recognition, synthetic olfactory perceptions and provides feedback control to the initial stages of the olfactory pathway. This article presents some of the challenges in olfactory information processing and then reviews our current knowledge of the mechanisms by which the olfactory bulb and olfactory cortex represent odours and analyse olfactory information.