Trait Openness and serotonin 2A receptors in healthy volunteers: A positron emission tomography study
Burmester, D., Fisher, P. M., Frokjaer, V. G., Knudsen, G. M., Kristiansen, S., Madsen, M. K., Stenbæk, D. S.
This positron emission tomography (PET) study (n=159) found no relationship between the availability of 5-HT 2A receptors and variation in trait Openness in healthy individuals, even though psychedelic compounds such as psilocybin have been shown to increase trait openness and stimulate the 5HT2A receptor pathway.
Abstract
Introduction: Recent research found lasting increases in personality trait Openness in healthy individuals and patients after administration of the serotonin 2A receptor (5-HT2AR) agonist psilocybin. However, no studies have investigated whether 5-HT2AR availability as imaged using positron emission tomography (PET) is associated with this trait.Methods: In 159 healthy individuals (53 females), the association between 5-HT 2AR binding in neocortex imaged with [18F]altanserin or [11C]Cimbi-36 PET and personality trait Openness was investigated using linear regression models. In these models the influence of sex on the association was also investigated. Trait Openness was assessed with the NEO Personality Inventory-Revised.Results: No significant associations between neocortical 5-HT2AR bind-ing and trait Openness were found for [18 F]altanserin (p =0.5)or[11C]Cimbi-36 (p = 0.8). Pooling the data in a combined model did not substantially change our results (p =0.4). No significant interactions with sex were found (p > 0.35).Discussion: Our results indicate that differences in 5-HT 2AR availability are not related to variations in trait Openness in healthy individuals. Although stimulation of the 5-HT 2AR with compounds such as psilocybin may contribute to long-term changes in trait Open-ness, there is no evidence in favor of an association between 5-HT 2AR and trait Openness.