Imaging of brain activation by odorants in humans

Application of positron emission tomography and magnetic resonance imaging has provided several new insights into various olfactory functions. One is that sniffing and smelling engage separate subsystems in the human olfactory cortex. Another is that perception of odorous compounds (odorants) is mediated by a set of core regions, which are partly different for pure olfactory than for olfactory plus trigeminal odorants. Depending on the task associated with odor perception, the core regions are recruited together with other circuits, in a parallel and hierarchical manner. The sense of smell seems, therefore, to be organized similarly to other sensory modalities, and the specific psychophysical characteristics of olfaction should be attributed to an early involvement of the limbic system rather than to a conceptually different mode of processing.

[1]  J. Pardo,et al.  Emotion, olfaction, and the human amygdala: amygdala activation during aversive olfactory stimulation. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[2]  I. Savic,et al.  Odorous stimuli are processed differently depending on the cranial nerves involved , 2000, NeuroImage.

[3]  N. Costes,et al.  Emotional Responses to Pleasant and Unpleasant Olfactory, Visual, and Auditory Stimuli: a Positron Emission Tomography Study , 2000, The Journal of Neuroscience.

[4]  B. Gulyás,et al.  Brain activation during odor perception in males and females , 2001, Neuroreport.

[5]  S. Takagi.  Olfactory Frontal Cortex and Multiple Olfactory Processing in Primates , 1991 .

[6]  J. D. E. Gabrieli,et al.  Sniffing and smelling: separate subsystems in the human olfactory cortex , 1998, Nature.

[7]  Gary H. Glover,et al.  Odorant-Induced and Sniff-Induced Activation in the Cerebellum of the Human , 1998, The Journal of Neuroscience.

[8]  M. Bushnell,et al.  Dissociation of sensory and affective dimensions of pain using hypnotic modulation , 1999, Pain.

[9]  L. Kinnunen,et al.  Sustained human chemosignal unconsciously alters brain function , 2001, Neuroreport.

[10]  J. Desmond,et al.  Blind smell: brain activation induced by an undetected air-borne chemical. , 1999, Brain : a journal of neurology.

[11]  P. Jurs,et al.  Intranasal trigeminal stimulation from odorous volatiles: Psychometric responses from anosmic and normal humans , 1978, Physiology & Behavior.

[12]  G H Glover,et al.  Time course of odorant-induced activation in the human primary olfactory cortex. , 2000, Journal of neurophysiology.

[13]  B. Gulyás,et al.  Odorant differentiated pattern of cerebral activation: Comparison of acetone and vanillin , 2002, Human brain mapping.

[14]  D. J. Felleman,et al.  Distributed hierarchical processing in the primate cerebral cortex. , 1991, Cerebral cortex.

[15]  K. Døving,et al.  The vomeronasal cavity in adult humans. , 2000, Chemical senses.

[16]  C. S. Lin,et al.  Functional MRI of human olfaction. , 1997, Journal of computer assisted tomography.

[17]  D. Tank,et al.  Brain magnetic resonance imaging with contrast dependent on blood oxygenation. , 1990, Proceedings of the National Academy of Sciences of the United States of America.

[18]  C. S. Lin,et al.  Rapid imaging of olfaction by functional MRI (fMRI): identification of presence and type of hyposmia. , 1999, Journal of computer assisted tomography.

[19]  S. Ogawa.  Brain magnetic resonance imaging with contrast-dependent oxygenation , 1990 .

[20]  D. Yousem,et al.  Gender effects on odor-stimulated functional magnetic resonance imaging , 1999, Brain Research.

[21]  M J Brammer,et al.  Functional MR imaging during odor stimulation: preliminary data. , 1997, Radiology.

[22]  R. Zatorre,et al.  Neural mechanisms involved in odor pleasantness and intensity judgments , 2000, Neuroreport.

[23]  Gilles Sicard,et al.  Functional Anatomy of Perceptual and Semantic Processing for Odors , 1999, Journal of Cognitive Neuroscience.

[24]  J. Frahm,et al.  Direct FLASH MR imaging of magnetic field inhomogeneities by gradient compensation , 1988, Magnetic resonance in medicine.

[25]  Alan C. Evans,et al.  Human Brain Function during Odor Encoding and Recognition: A PET Activation Study a , 1998, Annals of the New York Academy of Sciences.

[26]  B. Gulyás,et al.  Olfactory Functions Are Mediated by Parallel and Hierarchical Processing , 2000, Neuron.

[27]  I Savic,et al.  Olfactory bedside test. A simple approach to identify temporo-orbitofrontal dysfunction. , 1997, Archives of neurology.

[28]  B. Gulyás,et al.  Smelling of Odorous Sex Hormone-like Compounds Causes Sex-Differentiated Hypothalamic Activations in Humans , 2001, Neuron.

[29]  Alan C. Evans,et al.  Functional localization and lateralization of human olfactory cortex , 1992, Nature.