Handedness is a determining factor in lateralized olfactory discrimination

Abstract

The study aimed to re-investigate differences in olfactory thresholds and odor discrimination between the left and right sides in relation to the handedness of healthy subjects. Twenty left- and 20 right-handers participated; all were in excellent health with no indication of any major nasal or health problems, and all were non-smokers. The two groups were comparable in terms of sex and age (left-handers: 11 women, 9 men, median age 25 years; right-handers: 9 women, 11 men, median age 26 years). Odor thresholds did not differ in relation to handedness. However, in the odor discrimination task the left-handers performed significantly better at the left side compared with the right nostril; this pattern was reversed in the right-handers. The data indicate that, similar to other sensory systems, higher olfactory functions exhibit a certain degree of lateralization.

Unilateral reduced sense of smell is an early indicator for global olfactory loss

“…Handedness can impact on lateralized olfactory function [1,18]. Most of the investigated participants of the ''difference group'' and the ''control group'' were right handed.…”

The Color of Odors

“…The weak relationship between odors and language is probably due to the proposed lateralization of brain areas involved in the processing of language and smell. Indeed, for most people, linguistic processing is primarily a left hemisphere activity Frost, et al, 1999;Knecht, et al, 2000;Lee et al, 1999) while odor perception is more lateralized to the right hemisphere (Dade et al, 1998;Herz et al, 1999;Hummel et al, 1998;Kobal & Kettenmann, 2000). However, data from the literature show that there is a controversy on this last point (Brand, 1999;Brand et al, 1999).…”

Dysfunction of the liver affects the sense of smell

“…This effect may be explained by the assumption that threshold measurements reflect the function of the peripheral olfactory system to a larger degree than other olfactory tests, and that odor identification and odor discrimination relate to higher order processing of olfactory input [21][22][23]. Thus, the observed differences in odor identification in relation to the severity of the disease may be explained, at least in part, by the correlation between odor identification and psychometric test results; this was not seen for odor thresholds or odor discrimination.…”