title: Odorant category profile selectivity of olfactory cortex neurons.
abstract: The olfactory cortex receives converging axonal inputs from many mitral and tufted cells in the olfactory bulb. Recent studies indicate that single cortical neurons integrate signals from diverse odorants. However, there remains a basic question, namely, the signals from which kinds of odorants are integrated by the individual cortical neurons? The present study examined the possibility that some cortical neurons integrate signals from distinct component odorants of natural foods because individual foods produce a fixed combination of odorants. Previous psychophysical studies of core odorants emitted by fruits and vegetables suggest that the olfactory images of individual natural foods are basically characterized by the profile of structural and perceptual categories of food-born odorants. The single-unit spike responses of neurons in the dorsoposterior part of rat anterior piriform cortex to a panel of eight food-related categories of odorants were herein examined. The results showed that many cortical neurons in this region are tuned selectively to either a single category or a specific combination of distinct categories. The cortical neurons showed mixture facilitation and mixture inhibition when stimulated with mixtures of distinct categories, thus suggesting that olfactory circuits may play a role in enhancing the category-profile selectivity of individual neurons. These results indicate that signals from distinct categories of food-born odorants are integrated in these cortical neurons. This suggests that these cortical neurons detect the odorant-category profile of foods to distinguish distinct food odors.
authors: Department of Physiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors: Ikue
authors: I
authors: Yoshida
authors: Kensaku
authors: K
authors: Mori
mesh_terms: D000200:Action Potentials; D000818:Animals; D004192:Discrimination, Psychological / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods; D005502:Food; D008297:Male; D009433:Neural Inhibition / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009812:Odorants; D009830:Olfactory Bulb / Q000166:cytology / Q000502:physiology; D009833:Olfactory Pathways / Q000166:cytology*; D051381:Rats; D017208:Rats, Wistar; D012684:Sensory Thresholds / Q000502:physiology; D012903:Smell / Q000502:physiology*
references: Chem Senses. 2001 Jun;26(5):577-84
references: 11418503
references: Nature. 2001 Nov 8;414(6860):173-9
references: 11700549
references: Biochem Soc Trans. 2003 Feb;31(Pt 1):147-51
references: 12546673
references: J Neurophysiol. 2003 Jul;90(1):65-72
references: 12660351
references: Eur J Neurosci. 2003 Jun;17(11):2457-61
references: 12814377
references: J Agric Food Chem. 2004 Mar 10;52(5):1248-54
references: 14995129
references: J Neurophysiol. 2004 Oct;92(4):2413-27
references: 15152015
references: Neuron. 2005 Apr 21;46(2):285-96
references: 15848806
references: Proc Natl Acad Sci U S A. 2005 May 24;102(21):7724-9
references: 15911779
references: J Neurophysiol. 2006 Mar;95(3):1888-96
references: 16251260
references: Science. 2006 Feb 10;311(5762):815-9
references: 16469919
references: Science. 2006 Mar 10;311(5766):1477-81
references: 16527983
references: Physiol Rev. 2006 Apr;86(2):409-33
references: 16601265
references: J Neurosci. 2006 Nov 15;26(46):12023-32
references: 17108176
references: Nature. 2006 Nov 16;444(7117):316-21
references: 17108956
references: Am J Primatol. 2007 Mar;69(3):282-94
references: 17146790
references: J R Soc Interface. 2007 Apr 22;4(13):331-40
references: 17251141
references: J Neurosci. 2007 Feb 14;27(7):1534-42
references: 17301162
references: Cell. 1991 Apr 5;65(1):175-87
references: 1840504
references: Experientia. 1986 Mar 15;42(3):257-71
references: 3514263
references: Anim Behav. 1968 Feb;16(1):13-7
references: 5639893
references: J Comp Neurol. 1977 Mar 1;172(1):1-35
references: 65361
references: Brain Res. 1977 Jun 24;129(1):152-7
references: 68803
references: J Comp Neurol. 1982 Aug 10;209(3):249-63
references: 7130455
references: J Comp Neurol. 1980 Dec 1;194(3):519-34
references: 7451680
references: Annu Rev Neurosci. 1996;19:517-44
references: 8833453
references: J Neurophysiol. 1998 Mar;79(3):1425-40
references: 9497422