The relationship of olfactory abilities and anxiety in adolescents and young adults

Current research shows that neuroticity is the most striking candidate among personality traits which  can influence olfactory perception or more precisely olfactory abilities. The relationship between neuroticity and olfactory perception is based on the relationship between the olfactory and limbic systems: the “olfactory brain” contains the limbic structures of amygdala and hippocampus (see Hawkes & Doty, 2009; Zald & Pardo, 2000) which also take part in processing and regulation of emotions (Davis & Whalen, 2001; Dolcos, LaBar, & Cabeza, 2005; LeDoux, 2003; Tottenham & Sheridan, 2010). Since individuals with high levels of anxiety exhibit structural and/or functional changes in the amygdala and hippocampus (Bremner, 2004; Milad, Rauch, Pitman, & Quirk, 2006), it is possible that the processing of olfactory information will be affected.

The aim of the research was to find out the possible link between olfactory abilities and neuroticity in adolescents and young adults. The body of participants in Study 1 consisted of 71 adolescents (41 of which were women) aged 17-22 (18.0 ± 0.81) years and in Study 2 of 156 young adults (67 of which were women) aged 19-35 (24.2 ± 4,2) years. The sample in Study 2 was notable for its even ratio of heterosexually and non-heterosexually oriented individuals; for details see the following study (Nováková et al., in press). The participants were asked to fill in the Czech version of the Revised NEO Personality Inventory (NEO-PI-R, Hřebíčková, 2004) in Study 1 and its shorter version NEO-Five Factor Inventory in Study 2 (NEO-FFI, Hřebíčková & Urbánek, 2001) (Omega et al., 1997). In addition they underwent tests of olfactory abilites – identification and olfactory sensitivity (threshold) in Study 1 and additionally in Study 2 a test of ability to discriminate odours with using olfactory pens  – Sniffin’ Sticks (Hummel et al., 1997).

In Study 1, a positive correlation was found between the score on the dimension of neuroticism and the olfactory sensitivity (threshold), to which the scores on the subscales of anxiety and embarrassment contributed the most. In Study 2, the connection between anxiety and the sense of smell was found again, particularly by the ability to discriminate odours. These findings are in line with the results of a recent study that showed a faster detection of odours in highly anxious individuals (La Buissonnière-Ariza, Lepore, Kojok, & Frasnelli, 2013). However, in order to make more general conclusions about the effect of anxiety as a personality trait on olfactory perception and specifically on olfactory abilities, further studies will be needed to address multiple tasks. Because depending on whether or not anxiety aggravates or improves performance in olfactory testing, it depends on the difficulty and nature of the task, among other things (Eysenck & Calvo, 1992). However, it may already be useful to control for the effect of anxiety on results in olfactory tests.