While biological models of human personality propose that socio-affective traits and skills are rooted in the structure of the amygdala, empirical evidence remains sparse and inconsistent. Here, we used a comprehensive assessment of the affective personality and tested its association with global, local, and laterality measures of the amygdala structure. Results revealed three broad dimensions of the affective personality that were differentially related to bilateral amygdala structures. Dysfunctional and maladaptive affective traits were associated with a global size and local volume reduction of the amygdala, whereas adaptive emotional skills were linked to an increased size of the left amygdala. Furthermore, reduced asymmetry in the bilateral global amygdala volume was linked to higher affective instability and might be a potential precursor of psychiatric disorders. This study demonstrates that structural amygdala measures provide a neural basis for all major dimensions of the human personality related to adaptive and maladaptive socio-affective functioning.
