Association between irritable temperament and glucose metabolism in the left insula and the right cerebellum.

INTRODUCTION

Affective temperaments are assumed to have biological and neural bases. In the present study, we analyzed 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) images of healthy participants to explore the neural basis of affective temperaments.

METHOD: We utilized data of affective temperament measured by the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire and 18F-FDG PET images of healthy participants from two of our previous studies. A multiple regression analysis was performed to assess the association between 18F-FDG uptake and temperament scores using Statistical Parametric Mapping 12.

RESULTS

The final sample included 62 healthy participants. Whole-brain analysis revealed a cluster of 18F-FDG uptake that was significantly and positively associated with irritable temperament scores in the right cerebellum (Crus II, VIII, and IX). After further adjustment for the other four temperament scores, whole-brain analysis revealed a cluster of 18F-FDG uptake significantly and positively associated with irritable temperament scores in the left insula and right cerebellum (Crus II, VIII, and IX). However, no significant association was found between 18F-FDG uptake and the other four temperaments (depressive, cyclothymic, hyperthymic, and anxious).

CONCLUSIONS

The left insula and right cerebellum of the cerebrocerebellar circuit may be one of the neural bases of irritable temperament.