Chemosensory Evoked Potentials
Research on human olfaction is complicated by the fact that, at sufficiently high concentrations, many odorants produce trigeminallymediated sensations. Therefore, most patients with complete anosmia still are able to respond to a great variety of substances. For example, menthol and eucalyptol produce cooling or even stinging sensations at higher concentrations. Doty et al. (1978) found that in 15 anosmic patients, only vanillin and phenyl ethyl alcohol were not discernible by irritation or other somatosensory sensations (out of a total of 47 odorants). Our own studies in patients with Kallman’s syndrome (Hummel, Pietsch and Kobal, 1991) revealed that they also were unable to perceive hydrogen sulfide. The function of the t.rigeminal nerve may be assessed, in the absence of olfactory stimulation, by means of the non-odorous stimulus carbon dioxide (CO2), which reportedly produces only painful sensations (Thurauf et al., 1991).
KeywordsHydrogen Sulfide Temporal Lobe Epilepsy Phenyl Ethyl Olfactory Function Isoamyl Acetate
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